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1

Introduction

Chapter 1

2

10 Technology Revolution

bull 18th Century Mechanical systems

bull 19th Century Steam Engine

bull 20th Century Information

- gathering

- distribution

- processing

- creating

3

A set of communication elements connected by communication links

Communication elements Computers printers mobile phones hellip Routers switches

Communication links optic fiber coaxial cable twisted pair wireless (radio microwave satellite)

Topologies Ring Star Bus Tree Mesh

What is a Computer Network

local ISP

companynetwork

regional ISP

router workstation

servermobile

4

A softwarehardware infrastructure

Share resources data files computing power videohellip

Information highway communication between geographically dispersed users

Electronic Society Cyberspace Virtual global nation

What is a Computer Network

5

Introduction Computer Network

ndash an interconnected collection of autonomous computersInternet ldquonetwork of networksrdquo

ndash loosely hierarchical

ndash public Internet versus private intranet

WWW a distributed systems run on the top of Internet

Distributed System

ndash High degree of cohesiveness and transparencyndash A software system built on top of a network

6

11 Uses of Computer Networks

bull Business Applications

bull Home Applications

bull Mobile Users

bull Social Issues

7

Business Applications of Networks

A network with two clients and one server

a Resource sharing (hardware software information hellip)

c Doing business electronically (B2B B2C e-commerce)

b Providing communication medium (e-mail videoconferenceing)

8

Goals of Networks for Companies Resource sharing equipment programs data high reliability

ndash replicated data

ndash hardware Saving money

ndash mainframe 10 times faster but 1000 times more expensive than PC

ndash client-server model Scalability

ndash mainframe replace a larger one

ndash client-server model add more servers Communication medium for separated employees

9

Business Applications of Networks (2)

The client-server model involves requests and replies

a Two processes are involved

b A communication network is needed

10

Home Network Applications

bull Access to remote information

bull Person-to-person communication

bull Interactive entertainment

bull Electronic commerce

11

Networks for Peoplendash Access to remote information

bull eg financial shopping customized newspapers on-line digital library WWW

ndash Person-to-person communicationbull email video conference newsgroup

ndash Interactive entertainmentbull VOD interactive movies or TVs game playing

12

Home Network Applications (2)

In peer-to-peer system there are no fixed clients and servers

13

Home Network Applications (3)

Some forms of e-commerce

14

Mobile Network Users

Combinations of wireless networks and mobile computing

mobile-commerce

15

Social Issues

bull Politics

bull Religion

bull Sex

bull Privacy

bull Crime

bull junk mail ill-information Each country has different laws Debate rages

16

Network Hardware

bull Local Area Networks

bull Metropolitan Area Networks

bull Wide Area Networks

bull Wireless Networks

bull Home Networks

bull Internetworks

17

Types of transmission technology

bull Broadcast links

bull Point-to-point links

Network Hardware

18

Network Hardwarendash Broadcast networks

bull single communication channel shared by all machines

bull broadcasting or multicasting (via packets)ndash broadcasting a special code in address field

ndash multicasting reserve one bit to indicate multicasting the remaining n-1address bits can hold a group number Each machine can subscribe to any groups

bull used by localized networks (or satellites)

ndash point-to-point networksbull many hops

bull routing algorithms multiple routs are possible

bull used by large networks

19

Classification of interconnected processors by scale

20

Local Area Networks (LANs)

Two broadcast networks(a) Bus(b) Ring

middot Characterics of LANs (a) privated-owned (b) small size (c) transmission technology (d) topology

middot Ethernets are most popular (up to 10 Gbs)

21

Local Area Networks Characteristics

ndash small size

ndash transmission technologybull single cable

bull 10Mbps ~ 10Gbs

bull 10Gbs 10000000000 bps

ndash topology

bull bus

ndash Ethernet (IEEE 8023) 10 or 100 Mbps (10Gbs)

bull ring

ndash IBM token ring (IEEE 8025) 4 or 16 Mbps

Channel allocation of broadcast networksndash static each machine has an allocated time slot

ndash dynamic

22

Metropolitan Area Networks

A metropolitan area network based on cable TV

23

Wide Area Networks (WANs)

Relation between hosts on LANs and the subnet

middotWANs are point-to-point networks

middotWANs consist of two distinct components transmission lines (copper fiber microwave) and switches (electronics optics)

Store-and-forward or packet-switched subnet

24

Network Topology

25

Subnet (WANs)Subnet (WANs) is consists of two components

ndash transmission lines (circuits channels trunks)bull move bits between machines

ndash switching elementsbull connect transmission lines

bull Router also called packet switching nodes intermediate systems and data switching exchanges

bull Operate in store-and-forward or packet-switched mode

26

Wide Area Networks (2)

A stream of packets from sender to receiver (virtual- circuit)

Routing decisions are made locallymiddot How A makes that decision is called the routing algorithm Will be studied in detail in Chapter 5

917 End

27

Wireless Networks

Categories of wireless networksbull System interconnection

(short-range radio eg Bluetooth)bull Wireless LANs

(80211a 80211b 80211g)bull Wireless WANs

(80216 Cellular telephones Satellites)bull Wireless sensor networks

28

Wireless Networks (2)

(a) Bluetooth configuration(b) Wireless LAN

29

Wireless Networks (3)

(a) Individual mobile computers(b) A flying LAN

30

Home Network Categories

Computers (desktop PC PDA shared peripherals) Entertainment (TV DVD VCR camera stereo MP3) Telecomm (telephone cell phone intercom fax) Appliances (microwave fridge clock furnace airco

light) Telemetry (utility meter smokeburglar alarm babycam)

31

Fundamentally different properties

1 Devices have to be easy to install

2 The network and devices have to be foolproof in

operation

3 Low price is essential

4 The network needs sufficient capacity ( for multimedia

application)

5 The network interface and wiring have to be stable for

many years

6 Security and reliability will be very important

(minimize false alarm or misalarm) Home networks may be wired or wireless

32

Internetworks

bull Internetworks connect networks with different hardware

and softwarebull A collection of interconnected networks is called

an internetwork or internetbull Internet is one specific internetbull Gateways are used to make the connection and to

provide the necessary translation (protocol convertion)

33

Network Software

bull Protocol Hierarchies (Layer structure)bull Design Issues for the Layersbull Connection-Oriented and Connectionless Servicesbull Service Primitivesbull The Relationship of Services to Protocols

34

Network Software

Protocol Hierarchiesndash a series of layers (levels)

ndash lower layer provides service to higher layers

ndash protocol bull an agreement between the communication parties on how

communication is to proceed

ndash Peers bull the corresponding layers on different machines

ndash Network architecture a set of layers and protocols

ndash Protocol stack bull a list of protocols used by a certain system one protocol per

layer

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

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2

10 Technology Revolution

bull 18th Century Mechanical systems

bull 19th Century Steam Engine

bull 20th Century Information

- gathering

- distribution

- processing

- creating

3

A set of communication elements connected by communication links

Communication elements Computers printers mobile phones hellip Routers switches

Communication links optic fiber coaxial cable twisted pair wireless (radio microwave satellite)

Topologies Ring Star Bus Tree Mesh

What is a Computer Network

local ISP

companynetwork

regional ISP

router workstation

servermobile

4

A softwarehardware infrastructure

Share resources data files computing power videohellip

Information highway communication between geographically dispersed users

Electronic Society Cyberspace Virtual global nation

What is a Computer Network

5

Introduction Computer Network

ndash an interconnected collection of autonomous computersInternet ldquonetwork of networksrdquo

ndash loosely hierarchical

ndash public Internet versus private intranet

WWW a distributed systems run on the top of Internet

Distributed System

ndash High degree of cohesiveness and transparencyndash A software system built on top of a network

6

11 Uses of Computer Networks

bull Business Applications

bull Home Applications

bull Mobile Users

bull Social Issues

7

Business Applications of Networks

A network with two clients and one server

a Resource sharing (hardware software information hellip)

c Doing business electronically (B2B B2C e-commerce)

b Providing communication medium (e-mail videoconferenceing)

8

Goals of Networks for Companies Resource sharing equipment programs data high reliability

ndash replicated data

ndash hardware Saving money

ndash mainframe 10 times faster but 1000 times more expensive than PC

ndash client-server model Scalability

ndash mainframe replace a larger one

ndash client-server model add more servers Communication medium for separated employees

9

Business Applications of Networks (2)

The client-server model involves requests and replies

a Two processes are involved

b A communication network is needed

10

Home Network Applications

bull Access to remote information

bull Person-to-person communication

bull Interactive entertainment

bull Electronic commerce

11

Networks for Peoplendash Access to remote information

bull eg financial shopping customized newspapers on-line digital library WWW

ndash Person-to-person communicationbull email video conference newsgroup

ndash Interactive entertainmentbull VOD interactive movies or TVs game playing

12

Home Network Applications (2)

In peer-to-peer system there are no fixed clients and servers

13

Home Network Applications (3)

Some forms of e-commerce

14

Mobile Network Users

Combinations of wireless networks and mobile computing

mobile-commerce

15

Social Issues

bull Politics

bull Religion

bull Sex

bull Privacy

bull Crime

bull junk mail ill-information Each country has different laws Debate rages

16

Network Hardware

bull Local Area Networks

bull Metropolitan Area Networks

bull Wide Area Networks

bull Wireless Networks

bull Home Networks

bull Internetworks

17

Types of transmission technology

bull Broadcast links

bull Point-to-point links

Network Hardware

18

Network Hardwarendash Broadcast networks

bull single communication channel shared by all machines

bull broadcasting or multicasting (via packets)ndash broadcasting a special code in address field

ndash multicasting reserve one bit to indicate multicasting the remaining n-1address bits can hold a group number Each machine can subscribe to any groups

bull used by localized networks (or satellites)

ndash point-to-point networksbull many hops

bull routing algorithms multiple routs are possible

bull used by large networks

19

Classification of interconnected processors by scale

20

Local Area Networks (LANs)

Two broadcast networks(a) Bus(b) Ring

middot Characterics of LANs (a) privated-owned (b) small size (c) transmission technology (d) topology

middot Ethernets are most popular (up to 10 Gbs)

21

Local Area Networks Characteristics

ndash small size

ndash transmission technologybull single cable

bull 10Mbps ~ 10Gbs

bull 10Gbs 10000000000 bps

ndash topology

bull bus

ndash Ethernet (IEEE 8023) 10 or 100 Mbps (10Gbs)

bull ring

ndash IBM token ring (IEEE 8025) 4 or 16 Mbps

Channel allocation of broadcast networksndash static each machine has an allocated time slot

ndash dynamic

22

Metropolitan Area Networks

A metropolitan area network based on cable TV

23

Wide Area Networks (WANs)

Relation between hosts on LANs and the subnet

middotWANs are point-to-point networks

middotWANs consist of two distinct components transmission lines (copper fiber microwave) and switches (electronics optics)

Store-and-forward or packet-switched subnet

24

Network Topology

25

Subnet (WANs)Subnet (WANs) is consists of two components

ndash transmission lines (circuits channels trunks)bull move bits between machines

ndash switching elementsbull connect transmission lines

bull Router also called packet switching nodes intermediate systems and data switching exchanges

bull Operate in store-and-forward or packet-switched mode

26

Wide Area Networks (2)

A stream of packets from sender to receiver (virtual- circuit)

Routing decisions are made locallymiddot How A makes that decision is called the routing algorithm Will be studied in detail in Chapter 5

917 End

27

Wireless Networks

Categories of wireless networksbull System interconnection

(short-range radio eg Bluetooth)bull Wireless LANs

(80211a 80211b 80211g)bull Wireless WANs

(80216 Cellular telephones Satellites)bull Wireless sensor networks

28

Wireless Networks (2)

(a) Bluetooth configuration(b) Wireless LAN

29

Wireless Networks (3)

(a) Individual mobile computers(b) A flying LAN

30

Home Network Categories

Computers (desktop PC PDA shared peripherals) Entertainment (TV DVD VCR camera stereo MP3) Telecomm (telephone cell phone intercom fax) Appliances (microwave fridge clock furnace airco

light) Telemetry (utility meter smokeburglar alarm babycam)

31

Fundamentally different properties

1 Devices have to be easy to install

2 The network and devices have to be foolproof in

operation

3 Low price is essential

4 The network needs sufficient capacity ( for multimedia

application)

5 The network interface and wiring have to be stable for

many years

6 Security and reliability will be very important

(minimize false alarm or misalarm) Home networks may be wired or wireless

32

Internetworks

bull Internetworks connect networks with different hardware

and softwarebull A collection of interconnected networks is called

an internetwork or internetbull Internet is one specific internetbull Gateways are used to make the connection and to

provide the necessary translation (protocol convertion)

33

Network Software

bull Protocol Hierarchies (Layer structure)bull Design Issues for the Layersbull Connection-Oriented and Connectionless Servicesbull Service Primitivesbull The Relationship of Services to Protocols

34

Network Software

Protocol Hierarchiesndash a series of layers (levels)

ndash lower layer provides service to higher layers

ndash protocol bull an agreement between the communication parties on how

communication is to proceed

ndash Peers bull the corresponding layers on different machines

ndash Network architecture a set of layers and protocols

ndash Protocol stack bull a list of protocols used by a certain system one protocol per

layer

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
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3

A set of communication elements connected by communication links

Communication elements Computers printers mobile phones hellip Routers switches

Communication links optic fiber coaxial cable twisted pair wireless (radio microwave satellite)

Topologies Ring Star Bus Tree Mesh

What is a Computer Network

local ISP

companynetwork

regional ISP

router workstation

servermobile

4

A softwarehardware infrastructure

Share resources data files computing power videohellip

Information highway communication between geographically dispersed users

Electronic Society Cyberspace Virtual global nation

What is a Computer Network

5

Introduction Computer Network

ndash an interconnected collection of autonomous computersInternet ldquonetwork of networksrdquo

ndash loosely hierarchical

ndash public Internet versus private intranet

WWW a distributed systems run on the top of Internet

Distributed System

ndash High degree of cohesiveness and transparencyndash A software system built on top of a network

6

11 Uses of Computer Networks

bull Business Applications

bull Home Applications

bull Mobile Users

bull Social Issues

7

Business Applications of Networks

A network with two clients and one server

a Resource sharing (hardware software information hellip)

c Doing business electronically (B2B B2C e-commerce)

b Providing communication medium (e-mail videoconferenceing)

8

Goals of Networks for Companies Resource sharing equipment programs data high reliability

ndash replicated data

ndash hardware Saving money

ndash mainframe 10 times faster but 1000 times more expensive than PC

ndash client-server model Scalability

ndash mainframe replace a larger one

ndash client-server model add more servers Communication medium for separated employees

9

Business Applications of Networks (2)

The client-server model involves requests and replies

a Two processes are involved

b A communication network is needed

10

Home Network Applications

bull Access to remote information

bull Person-to-person communication

bull Interactive entertainment

bull Electronic commerce

11

Networks for Peoplendash Access to remote information

bull eg financial shopping customized newspapers on-line digital library WWW

ndash Person-to-person communicationbull email video conference newsgroup

ndash Interactive entertainmentbull VOD interactive movies or TVs game playing

12

Home Network Applications (2)

In peer-to-peer system there are no fixed clients and servers

13

Home Network Applications (3)

Some forms of e-commerce

14

Mobile Network Users

Combinations of wireless networks and mobile computing

mobile-commerce

15

Social Issues

bull Politics

bull Religion

bull Sex

bull Privacy

bull Crime

bull junk mail ill-information Each country has different laws Debate rages

16

Network Hardware

bull Local Area Networks

bull Metropolitan Area Networks

bull Wide Area Networks

bull Wireless Networks

bull Home Networks

bull Internetworks

17

Types of transmission technology

bull Broadcast links

bull Point-to-point links

Network Hardware

18

Network Hardwarendash Broadcast networks

bull single communication channel shared by all machines

bull broadcasting or multicasting (via packets)ndash broadcasting a special code in address field

ndash multicasting reserve one bit to indicate multicasting the remaining n-1address bits can hold a group number Each machine can subscribe to any groups

bull used by localized networks (or satellites)

ndash point-to-point networksbull many hops

bull routing algorithms multiple routs are possible

bull used by large networks

19

Classification of interconnected processors by scale

20

Local Area Networks (LANs)

Two broadcast networks(a) Bus(b) Ring

middot Characterics of LANs (a) privated-owned (b) small size (c) transmission technology (d) topology

middot Ethernets are most popular (up to 10 Gbs)

21

Local Area Networks Characteristics

ndash small size

ndash transmission technologybull single cable

bull 10Mbps ~ 10Gbs

bull 10Gbs 10000000000 bps

ndash topology

bull bus

ndash Ethernet (IEEE 8023) 10 or 100 Mbps (10Gbs)

bull ring

ndash IBM token ring (IEEE 8025) 4 or 16 Mbps

Channel allocation of broadcast networksndash static each machine has an allocated time slot

ndash dynamic

22

Metropolitan Area Networks

A metropolitan area network based on cable TV

23

Wide Area Networks (WANs)

Relation between hosts on LANs and the subnet

middotWANs are point-to-point networks

middotWANs consist of two distinct components transmission lines (copper fiber microwave) and switches (electronics optics)

Store-and-forward or packet-switched subnet

24

Network Topology

25

Subnet (WANs)Subnet (WANs) is consists of two components

ndash transmission lines (circuits channels trunks)bull move bits between machines

ndash switching elementsbull connect transmission lines

bull Router also called packet switching nodes intermediate systems and data switching exchanges

bull Operate in store-and-forward or packet-switched mode

26

Wide Area Networks (2)

A stream of packets from sender to receiver (virtual- circuit)

Routing decisions are made locallymiddot How A makes that decision is called the routing algorithm Will be studied in detail in Chapter 5

917 End

27

Wireless Networks

Categories of wireless networksbull System interconnection

(short-range radio eg Bluetooth)bull Wireless LANs

(80211a 80211b 80211g)bull Wireless WANs

(80216 Cellular telephones Satellites)bull Wireless sensor networks

28

Wireless Networks (2)

(a) Bluetooth configuration(b) Wireless LAN

29

Wireless Networks (3)

(a) Individual mobile computers(b) A flying LAN

30

Home Network Categories

Computers (desktop PC PDA shared peripherals) Entertainment (TV DVD VCR camera stereo MP3) Telecomm (telephone cell phone intercom fax) Appliances (microwave fridge clock furnace airco

light) Telemetry (utility meter smokeburglar alarm babycam)

31

Fundamentally different properties

1 Devices have to be easy to install

2 The network and devices have to be foolproof in

operation

3 Low price is essential

4 The network needs sufficient capacity ( for multimedia

application)

5 The network interface and wiring have to be stable for

many years

6 Security and reliability will be very important

(minimize false alarm or misalarm) Home networks may be wired or wireless

32

Internetworks

bull Internetworks connect networks with different hardware

and softwarebull A collection of interconnected networks is called

an internetwork or internetbull Internet is one specific internetbull Gateways are used to make the connection and to

provide the necessary translation (protocol convertion)

33

Network Software

bull Protocol Hierarchies (Layer structure)bull Design Issues for the Layersbull Connection-Oriented and Connectionless Servicesbull Service Primitivesbull The Relationship of Services to Protocols

34

Network Software

Protocol Hierarchiesndash a series of layers (levels)

ndash lower layer provides service to higher layers

ndash protocol bull an agreement between the communication parties on how

communication is to proceed

ndash Peers bull the corresponding layers on different machines

ndash Network architecture a set of layers and protocols

ndash Protocol stack bull a list of protocols used by a certain system one protocol per

layer

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
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  • Slide 82

4

A softwarehardware infrastructure

Share resources data files computing power videohellip

Information highway communication between geographically dispersed users

Electronic Society Cyberspace Virtual global nation

What is a Computer Network

5

Introduction Computer Network

ndash an interconnected collection of autonomous computersInternet ldquonetwork of networksrdquo

ndash loosely hierarchical

ndash public Internet versus private intranet

WWW a distributed systems run on the top of Internet

Distributed System

ndash High degree of cohesiveness and transparencyndash A software system built on top of a network

6

11 Uses of Computer Networks

bull Business Applications

bull Home Applications

bull Mobile Users

bull Social Issues

7

Business Applications of Networks

A network with two clients and one server

a Resource sharing (hardware software information hellip)

c Doing business electronically (B2B B2C e-commerce)

b Providing communication medium (e-mail videoconferenceing)

8

Goals of Networks for Companies Resource sharing equipment programs data high reliability

ndash replicated data

ndash hardware Saving money

ndash mainframe 10 times faster but 1000 times more expensive than PC

ndash client-server model Scalability

ndash mainframe replace a larger one

ndash client-server model add more servers Communication medium for separated employees

9

Business Applications of Networks (2)

The client-server model involves requests and replies

a Two processes are involved

b A communication network is needed

10

Home Network Applications

bull Access to remote information

bull Person-to-person communication

bull Interactive entertainment

bull Electronic commerce

11

Networks for Peoplendash Access to remote information

bull eg financial shopping customized newspapers on-line digital library WWW

ndash Person-to-person communicationbull email video conference newsgroup

ndash Interactive entertainmentbull VOD interactive movies or TVs game playing

12

Home Network Applications (2)

In peer-to-peer system there are no fixed clients and servers

13

Home Network Applications (3)

Some forms of e-commerce

14

Mobile Network Users

Combinations of wireless networks and mobile computing

mobile-commerce

15

Social Issues

bull Politics

bull Religion

bull Sex

bull Privacy

bull Crime

bull junk mail ill-information Each country has different laws Debate rages

16

Network Hardware

bull Local Area Networks

bull Metropolitan Area Networks

bull Wide Area Networks

bull Wireless Networks

bull Home Networks

bull Internetworks

17

Types of transmission technology

bull Broadcast links

bull Point-to-point links

Network Hardware

18

Network Hardwarendash Broadcast networks

bull single communication channel shared by all machines

bull broadcasting or multicasting (via packets)ndash broadcasting a special code in address field

ndash multicasting reserve one bit to indicate multicasting the remaining n-1address bits can hold a group number Each machine can subscribe to any groups

bull used by localized networks (or satellites)

ndash point-to-point networksbull many hops

bull routing algorithms multiple routs are possible

bull used by large networks

19

Classification of interconnected processors by scale

20

Local Area Networks (LANs)

Two broadcast networks(a) Bus(b) Ring

middot Characterics of LANs (a) privated-owned (b) small size (c) transmission technology (d) topology

middot Ethernets are most popular (up to 10 Gbs)

21

Local Area Networks Characteristics

ndash small size

ndash transmission technologybull single cable

bull 10Mbps ~ 10Gbs

bull 10Gbs 10000000000 bps

ndash topology

bull bus

ndash Ethernet (IEEE 8023) 10 or 100 Mbps (10Gbs)

bull ring

ndash IBM token ring (IEEE 8025) 4 or 16 Mbps

Channel allocation of broadcast networksndash static each machine has an allocated time slot

ndash dynamic

22

Metropolitan Area Networks

A metropolitan area network based on cable TV

23

Wide Area Networks (WANs)

Relation between hosts on LANs and the subnet

middotWANs are point-to-point networks

middotWANs consist of two distinct components transmission lines (copper fiber microwave) and switches (electronics optics)

Store-and-forward or packet-switched subnet

24

Network Topology

25

Subnet (WANs)Subnet (WANs) is consists of two components

ndash transmission lines (circuits channels trunks)bull move bits between machines

ndash switching elementsbull connect transmission lines

bull Router also called packet switching nodes intermediate systems and data switching exchanges

bull Operate in store-and-forward or packet-switched mode

26

Wide Area Networks (2)

A stream of packets from sender to receiver (virtual- circuit)

Routing decisions are made locallymiddot How A makes that decision is called the routing algorithm Will be studied in detail in Chapter 5

917 End

27

Wireless Networks

Categories of wireless networksbull System interconnection

(short-range radio eg Bluetooth)bull Wireless LANs

(80211a 80211b 80211g)bull Wireless WANs

(80216 Cellular telephones Satellites)bull Wireless sensor networks

28

Wireless Networks (2)

(a) Bluetooth configuration(b) Wireless LAN

29

Wireless Networks (3)

(a) Individual mobile computers(b) A flying LAN

30

Home Network Categories

Computers (desktop PC PDA shared peripherals) Entertainment (TV DVD VCR camera stereo MP3) Telecomm (telephone cell phone intercom fax) Appliances (microwave fridge clock furnace airco

light) Telemetry (utility meter smokeburglar alarm babycam)

31

Fundamentally different properties

1 Devices have to be easy to install

2 The network and devices have to be foolproof in

operation

3 Low price is essential

4 The network needs sufficient capacity ( for multimedia

application)

5 The network interface and wiring have to be stable for

many years

6 Security and reliability will be very important

(minimize false alarm or misalarm) Home networks may be wired or wireless

32

Internetworks

bull Internetworks connect networks with different hardware

and softwarebull A collection of interconnected networks is called

an internetwork or internetbull Internet is one specific internetbull Gateways are used to make the connection and to

provide the necessary translation (protocol convertion)

33

Network Software

bull Protocol Hierarchies (Layer structure)bull Design Issues for the Layersbull Connection-Oriented and Connectionless Servicesbull Service Primitivesbull The Relationship of Services to Protocols

34

Network Software

Protocol Hierarchiesndash a series of layers (levels)

ndash lower layer provides service to higher layers

ndash protocol bull an agreement between the communication parties on how

communication is to proceed

ndash Peers bull the corresponding layers on different machines

ndash Network architecture a set of layers and protocols

ndash Protocol stack bull a list of protocols used by a certain system one protocol per

layer

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
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  • Slide 82

5

Introduction Computer Network

ndash an interconnected collection of autonomous computersInternet ldquonetwork of networksrdquo

ndash loosely hierarchical

ndash public Internet versus private intranet

WWW a distributed systems run on the top of Internet

Distributed System

ndash High degree of cohesiveness and transparencyndash A software system built on top of a network

6

11 Uses of Computer Networks

bull Business Applications

bull Home Applications

bull Mobile Users

bull Social Issues

7

Business Applications of Networks

A network with two clients and one server

a Resource sharing (hardware software information hellip)

c Doing business electronically (B2B B2C e-commerce)

b Providing communication medium (e-mail videoconferenceing)

8

Goals of Networks for Companies Resource sharing equipment programs data high reliability

ndash replicated data

ndash hardware Saving money

ndash mainframe 10 times faster but 1000 times more expensive than PC

ndash client-server model Scalability

ndash mainframe replace a larger one

ndash client-server model add more servers Communication medium for separated employees

9

Business Applications of Networks (2)

The client-server model involves requests and replies

a Two processes are involved

b A communication network is needed

10

Home Network Applications

bull Access to remote information

bull Person-to-person communication

bull Interactive entertainment

bull Electronic commerce

11

Networks for Peoplendash Access to remote information

bull eg financial shopping customized newspapers on-line digital library WWW

ndash Person-to-person communicationbull email video conference newsgroup

ndash Interactive entertainmentbull VOD interactive movies or TVs game playing

12

Home Network Applications (2)

In peer-to-peer system there are no fixed clients and servers

13

Home Network Applications (3)

Some forms of e-commerce

14

Mobile Network Users

Combinations of wireless networks and mobile computing

mobile-commerce

15

Social Issues

bull Politics

bull Religion

bull Sex

bull Privacy

bull Crime

bull junk mail ill-information Each country has different laws Debate rages

16

Network Hardware

bull Local Area Networks

bull Metropolitan Area Networks

bull Wide Area Networks

bull Wireless Networks

bull Home Networks

bull Internetworks

17

Types of transmission technology

bull Broadcast links

bull Point-to-point links

Network Hardware

18

Network Hardwarendash Broadcast networks

bull single communication channel shared by all machines

bull broadcasting or multicasting (via packets)ndash broadcasting a special code in address field

ndash multicasting reserve one bit to indicate multicasting the remaining n-1address bits can hold a group number Each machine can subscribe to any groups

bull used by localized networks (or satellites)

ndash point-to-point networksbull many hops

bull routing algorithms multiple routs are possible

bull used by large networks

19

Classification of interconnected processors by scale

20

Local Area Networks (LANs)

Two broadcast networks(a) Bus(b) Ring

middot Characterics of LANs (a) privated-owned (b) small size (c) transmission technology (d) topology

middot Ethernets are most popular (up to 10 Gbs)

21

Local Area Networks Characteristics

ndash small size

ndash transmission technologybull single cable

bull 10Mbps ~ 10Gbs

bull 10Gbs 10000000000 bps

ndash topology

bull bus

ndash Ethernet (IEEE 8023) 10 or 100 Mbps (10Gbs)

bull ring

ndash IBM token ring (IEEE 8025) 4 or 16 Mbps

Channel allocation of broadcast networksndash static each machine has an allocated time slot

ndash dynamic

22

Metropolitan Area Networks

A metropolitan area network based on cable TV

23

Wide Area Networks (WANs)

Relation between hosts on LANs and the subnet

middotWANs are point-to-point networks

middotWANs consist of two distinct components transmission lines (copper fiber microwave) and switches (electronics optics)

Store-and-forward or packet-switched subnet

24

Network Topology

25

Subnet (WANs)Subnet (WANs) is consists of two components

ndash transmission lines (circuits channels trunks)bull move bits between machines

ndash switching elementsbull connect transmission lines

bull Router also called packet switching nodes intermediate systems and data switching exchanges

bull Operate in store-and-forward or packet-switched mode

26

Wide Area Networks (2)

A stream of packets from sender to receiver (virtual- circuit)

Routing decisions are made locallymiddot How A makes that decision is called the routing algorithm Will be studied in detail in Chapter 5

917 End

27

Wireless Networks

Categories of wireless networksbull System interconnection

(short-range radio eg Bluetooth)bull Wireless LANs

(80211a 80211b 80211g)bull Wireless WANs

(80216 Cellular telephones Satellites)bull Wireless sensor networks

28

Wireless Networks (2)

(a) Bluetooth configuration(b) Wireless LAN

29

Wireless Networks (3)

(a) Individual mobile computers(b) A flying LAN

30

Home Network Categories

Computers (desktop PC PDA shared peripherals) Entertainment (TV DVD VCR camera stereo MP3) Telecomm (telephone cell phone intercom fax) Appliances (microwave fridge clock furnace airco

light) Telemetry (utility meter smokeburglar alarm babycam)

31

Fundamentally different properties

1 Devices have to be easy to install

2 The network and devices have to be foolproof in

operation

3 Low price is essential

4 The network needs sufficient capacity ( for multimedia

application)

5 The network interface and wiring have to be stable for

many years

6 Security and reliability will be very important

(minimize false alarm or misalarm) Home networks may be wired or wireless

32

Internetworks

bull Internetworks connect networks with different hardware

and softwarebull A collection of interconnected networks is called

an internetwork or internetbull Internet is one specific internetbull Gateways are used to make the connection and to

provide the necessary translation (protocol convertion)

33

Network Software

bull Protocol Hierarchies (Layer structure)bull Design Issues for the Layersbull Connection-Oriented and Connectionless Servicesbull Service Primitivesbull The Relationship of Services to Protocols

34

Network Software

Protocol Hierarchiesndash a series of layers (levels)

ndash lower layer provides service to higher layers

ndash protocol bull an agreement between the communication parties on how

communication is to proceed

ndash Peers bull the corresponding layers on different machines

ndash Network architecture a set of layers and protocols

ndash Protocol stack bull a list of protocols used by a certain system one protocol per

layer

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
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6

11 Uses of Computer Networks

bull Business Applications

bull Home Applications

bull Mobile Users

bull Social Issues

7

Business Applications of Networks

A network with two clients and one server

a Resource sharing (hardware software information hellip)

c Doing business electronically (B2B B2C e-commerce)

b Providing communication medium (e-mail videoconferenceing)

8

Goals of Networks for Companies Resource sharing equipment programs data high reliability

ndash replicated data

ndash hardware Saving money

ndash mainframe 10 times faster but 1000 times more expensive than PC

ndash client-server model Scalability

ndash mainframe replace a larger one

ndash client-server model add more servers Communication medium for separated employees

9

Business Applications of Networks (2)

The client-server model involves requests and replies

a Two processes are involved

b A communication network is needed

10

Home Network Applications

bull Access to remote information

bull Person-to-person communication

bull Interactive entertainment

bull Electronic commerce

11

Networks for Peoplendash Access to remote information

bull eg financial shopping customized newspapers on-line digital library WWW

ndash Person-to-person communicationbull email video conference newsgroup

ndash Interactive entertainmentbull VOD interactive movies or TVs game playing

12

Home Network Applications (2)

In peer-to-peer system there are no fixed clients and servers

13

Home Network Applications (3)

Some forms of e-commerce

14

Mobile Network Users

Combinations of wireless networks and mobile computing

mobile-commerce

15

Social Issues

bull Politics

bull Religion

bull Sex

bull Privacy

bull Crime

bull junk mail ill-information Each country has different laws Debate rages

16

Network Hardware

bull Local Area Networks

bull Metropolitan Area Networks

bull Wide Area Networks

bull Wireless Networks

bull Home Networks

bull Internetworks

17

Types of transmission technology

bull Broadcast links

bull Point-to-point links

Network Hardware

18

Network Hardwarendash Broadcast networks

bull single communication channel shared by all machines

bull broadcasting or multicasting (via packets)ndash broadcasting a special code in address field

ndash multicasting reserve one bit to indicate multicasting the remaining n-1address bits can hold a group number Each machine can subscribe to any groups

bull used by localized networks (or satellites)

ndash point-to-point networksbull many hops

bull routing algorithms multiple routs are possible

bull used by large networks

19

Classification of interconnected processors by scale

20

Local Area Networks (LANs)

Two broadcast networks(a) Bus(b) Ring

middot Characterics of LANs (a) privated-owned (b) small size (c) transmission technology (d) topology

middot Ethernets are most popular (up to 10 Gbs)

21

Local Area Networks Characteristics

ndash small size

ndash transmission technologybull single cable

bull 10Mbps ~ 10Gbs

bull 10Gbs 10000000000 bps

ndash topology

bull bus

ndash Ethernet (IEEE 8023) 10 or 100 Mbps (10Gbs)

bull ring

ndash IBM token ring (IEEE 8025) 4 or 16 Mbps

Channel allocation of broadcast networksndash static each machine has an allocated time slot

ndash dynamic

22

Metropolitan Area Networks

A metropolitan area network based on cable TV

23

Wide Area Networks (WANs)

Relation between hosts on LANs and the subnet

middotWANs are point-to-point networks

middotWANs consist of two distinct components transmission lines (copper fiber microwave) and switches (electronics optics)

Store-and-forward or packet-switched subnet

24

Network Topology

25

Subnet (WANs)Subnet (WANs) is consists of two components

ndash transmission lines (circuits channels trunks)bull move bits between machines

ndash switching elementsbull connect transmission lines

bull Router also called packet switching nodes intermediate systems and data switching exchanges

bull Operate in store-and-forward or packet-switched mode

26

Wide Area Networks (2)

A stream of packets from sender to receiver (virtual- circuit)

Routing decisions are made locallymiddot How A makes that decision is called the routing algorithm Will be studied in detail in Chapter 5

917 End

27

Wireless Networks

Categories of wireless networksbull System interconnection

(short-range radio eg Bluetooth)bull Wireless LANs

(80211a 80211b 80211g)bull Wireless WANs

(80216 Cellular telephones Satellites)bull Wireless sensor networks

28

Wireless Networks (2)

(a) Bluetooth configuration(b) Wireless LAN

29

Wireless Networks (3)

(a) Individual mobile computers(b) A flying LAN

30

Home Network Categories

Computers (desktop PC PDA shared peripherals) Entertainment (TV DVD VCR camera stereo MP3) Telecomm (telephone cell phone intercom fax) Appliances (microwave fridge clock furnace airco

light) Telemetry (utility meter smokeburglar alarm babycam)

31

Fundamentally different properties

1 Devices have to be easy to install

2 The network and devices have to be foolproof in

operation

3 Low price is essential

4 The network needs sufficient capacity ( for multimedia

application)

5 The network interface and wiring have to be stable for

many years

6 Security and reliability will be very important

(minimize false alarm or misalarm) Home networks may be wired or wireless

32

Internetworks

bull Internetworks connect networks with different hardware

and softwarebull A collection of interconnected networks is called

an internetwork or internetbull Internet is one specific internetbull Gateways are used to make the connection and to

provide the necessary translation (protocol convertion)

33

Network Software

bull Protocol Hierarchies (Layer structure)bull Design Issues for the Layersbull Connection-Oriented and Connectionless Servicesbull Service Primitivesbull The Relationship of Services to Protocols

34

Network Software

Protocol Hierarchiesndash a series of layers (levels)

ndash lower layer provides service to higher layers

ndash protocol bull an agreement between the communication parties on how

communication is to proceed

ndash Peers bull the corresponding layers on different machines

ndash Network architecture a set of layers and protocols

ndash Protocol stack bull a list of protocols used by a certain system one protocol per

layer

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
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7

Business Applications of Networks

A network with two clients and one server

a Resource sharing (hardware software information hellip)

c Doing business electronically (B2B B2C e-commerce)

b Providing communication medium (e-mail videoconferenceing)

8

Goals of Networks for Companies Resource sharing equipment programs data high reliability

ndash replicated data

ndash hardware Saving money

ndash mainframe 10 times faster but 1000 times more expensive than PC

ndash client-server model Scalability

ndash mainframe replace a larger one

ndash client-server model add more servers Communication medium for separated employees

9

Business Applications of Networks (2)

The client-server model involves requests and replies

a Two processes are involved

b A communication network is needed

10

Home Network Applications

bull Access to remote information

bull Person-to-person communication

bull Interactive entertainment

bull Electronic commerce

11

Networks for Peoplendash Access to remote information

bull eg financial shopping customized newspapers on-line digital library WWW

ndash Person-to-person communicationbull email video conference newsgroup

ndash Interactive entertainmentbull VOD interactive movies or TVs game playing

12

Home Network Applications (2)

In peer-to-peer system there are no fixed clients and servers

13

Home Network Applications (3)

Some forms of e-commerce

14

Mobile Network Users

Combinations of wireless networks and mobile computing

mobile-commerce

15

Social Issues

bull Politics

bull Religion

bull Sex

bull Privacy

bull Crime

bull junk mail ill-information Each country has different laws Debate rages

16

Network Hardware

bull Local Area Networks

bull Metropolitan Area Networks

bull Wide Area Networks

bull Wireless Networks

bull Home Networks

bull Internetworks

17

Types of transmission technology

bull Broadcast links

bull Point-to-point links

Network Hardware

18

Network Hardwarendash Broadcast networks

bull single communication channel shared by all machines

bull broadcasting or multicasting (via packets)ndash broadcasting a special code in address field

ndash multicasting reserve one bit to indicate multicasting the remaining n-1address bits can hold a group number Each machine can subscribe to any groups

bull used by localized networks (or satellites)

ndash point-to-point networksbull many hops

bull routing algorithms multiple routs are possible

bull used by large networks

19

Classification of interconnected processors by scale

20

Local Area Networks (LANs)

Two broadcast networks(a) Bus(b) Ring

middot Characterics of LANs (a) privated-owned (b) small size (c) transmission technology (d) topology

middot Ethernets are most popular (up to 10 Gbs)

21

Local Area Networks Characteristics

ndash small size

ndash transmission technologybull single cable

bull 10Mbps ~ 10Gbs

bull 10Gbs 10000000000 bps

ndash topology

bull bus

ndash Ethernet (IEEE 8023) 10 or 100 Mbps (10Gbs)

bull ring

ndash IBM token ring (IEEE 8025) 4 or 16 Mbps

Channel allocation of broadcast networksndash static each machine has an allocated time slot

ndash dynamic

22

Metropolitan Area Networks

A metropolitan area network based on cable TV

23

Wide Area Networks (WANs)

Relation between hosts on LANs and the subnet

middotWANs are point-to-point networks

middotWANs consist of two distinct components transmission lines (copper fiber microwave) and switches (electronics optics)

Store-and-forward or packet-switched subnet

24

Network Topology

25

Subnet (WANs)Subnet (WANs) is consists of two components

ndash transmission lines (circuits channels trunks)bull move bits between machines

ndash switching elementsbull connect transmission lines

bull Router also called packet switching nodes intermediate systems and data switching exchanges

bull Operate in store-and-forward or packet-switched mode

26

Wide Area Networks (2)

A stream of packets from sender to receiver (virtual- circuit)

Routing decisions are made locallymiddot How A makes that decision is called the routing algorithm Will be studied in detail in Chapter 5

917 End

27

Wireless Networks

Categories of wireless networksbull System interconnection

(short-range radio eg Bluetooth)bull Wireless LANs

(80211a 80211b 80211g)bull Wireless WANs

(80216 Cellular telephones Satellites)bull Wireless sensor networks

28

Wireless Networks (2)

(a) Bluetooth configuration(b) Wireless LAN

29

Wireless Networks (3)

(a) Individual mobile computers(b) A flying LAN

30

Home Network Categories

Computers (desktop PC PDA shared peripherals) Entertainment (TV DVD VCR camera stereo MP3) Telecomm (telephone cell phone intercom fax) Appliances (microwave fridge clock furnace airco

light) Telemetry (utility meter smokeburglar alarm babycam)

31

Fundamentally different properties

1 Devices have to be easy to install

2 The network and devices have to be foolproof in

operation

3 Low price is essential

4 The network needs sufficient capacity ( for multimedia

application)

5 The network interface and wiring have to be stable for

many years

6 Security and reliability will be very important

(minimize false alarm or misalarm) Home networks may be wired or wireless

32

Internetworks

bull Internetworks connect networks with different hardware

and softwarebull A collection of interconnected networks is called

an internetwork or internetbull Internet is one specific internetbull Gateways are used to make the connection and to

provide the necessary translation (protocol convertion)

33

Network Software

bull Protocol Hierarchies (Layer structure)bull Design Issues for the Layersbull Connection-Oriented and Connectionless Servicesbull Service Primitivesbull The Relationship of Services to Protocols

34

Network Software

Protocol Hierarchiesndash a series of layers (levels)

ndash lower layer provides service to higher layers

ndash protocol bull an agreement between the communication parties on how

communication is to proceed

ndash Peers bull the corresponding layers on different machines

ndash Network architecture a set of layers and protocols

ndash Protocol stack bull a list of protocols used by a certain system one protocol per

layer

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
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  • Slide 82

8

Goals of Networks for Companies Resource sharing equipment programs data high reliability

ndash replicated data

ndash hardware Saving money

ndash mainframe 10 times faster but 1000 times more expensive than PC

ndash client-server model Scalability

ndash mainframe replace a larger one

ndash client-server model add more servers Communication medium for separated employees

9

Business Applications of Networks (2)

The client-server model involves requests and replies

a Two processes are involved

b A communication network is needed

10

Home Network Applications

bull Access to remote information

bull Person-to-person communication

bull Interactive entertainment

bull Electronic commerce

11

Networks for Peoplendash Access to remote information

bull eg financial shopping customized newspapers on-line digital library WWW

ndash Person-to-person communicationbull email video conference newsgroup

ndash Interactive entertainmentbull VOD interactive movies or TVs game playing

12

Home Network Applications (2)

In peer-to-peer system there are no fixed clients and servers

13

Home Network Applications (3)

Some forms of e-commerce

14

Mobile Network Users

Combinations of wireless networks and mobile computing

mobile-commerce

15

Social Issues

bull Politics

bull Religion

bull Sex

bull Privacy

bull Crime

bull junk mail ill-information Each country has different laws Debate rages

16

Network Hardware

bull Local Area Networks

bull Metropolitan Area Networks

bull Wide Area Networks

bull Wireless Networks

bull Home Networks

bull Internetworks

17

Types of transmission technology

bull Broadcast links

bull Point-to-point links

Network Hardware

18

Network Hardwarendash Broadcast networks

bull single communication channel shared by all machines

bull broadcasting or multicasting (via packets)ndash broadcasting a special code in address field

ndash multicasting reserve one bit to indicate multicasting the remaining n-1address bits can hold a group number Each machine can subscribe to any groups

bull used by localized networks (or satellites)

ndash point-to-point networksbull many hops

bull routing algorithms multiple routs are possible

bull used by large networks

19

Classification of interconnected processors by scale

20

Local Area Networks (LANs)

Two broadcast networks(a) Bus(b) Ring

middot Characterics of LANs (a) privated-owned (b) small size (c) transmission technology (d) topology

middot Ethernets are most popular (up to 10 Gbs)

21

Local Area Networks Characteristics

ndash small size

ndash transmission technologybull single cable

bull 10Mbps ~ 10Gbs

bull 10Gbs 10000000000 bps

ndash topology

bull bus

ndash Ethernet (IEEE 8023) 10 or 100 Mbps (10Gbs)

bull ring

ndash IBM token ring (IEEE 8025) 4 or 16 Mbps

Channel allocation of broadcast networksndash static each machine has an allocated time slot

ndash dynamic

22

Metropolitan Area Networks

A metropolitan area network based on cable TV

23

Wide Area Networks (WANs)

Relation between hosts on LANs and the subnet

middotWANs are point-to-point networks

middotWANs consist of two distinct components transmission lines (copper fiber microwave) and switches (electronics optics)

Store-and-forward or packet-switched subnet

24

Network Topology

25

Subnet (WANs)Subnet (WANs) is consists of two components

ndash transmission lines (circuits channels trunks)bull move bits between machines

ndash switching elementsbull connect transmission lines

bull Router also called packet switching nodes intermediate systems and data switching exchanges

bull Operate in store-and-forward or packet-switched mode

26

Wide Area Networks (2)

A stream of packets from sender to receiver (virtual- circuit)

Routing decisions are made locallymiddot How A makes that decision is called the routing algorithm Will be studied in detail in Chapter 5

917 End

27

Wireless Networks

Categories of wireless networksbull System interconnection

(short-range radio eg Bluetooth)bull Wireless LANs

(80211a 80211b 80211g)bull Wireless WANs

(80216 Cellular telephones Satellites)bull Wireless sensor networks

28

Wireless Networks (2)

(a) Bluetooth configuration(b) Wireless LAN

29

Wireless Networks (3)

(a) Individual mobile computers(b) A flying LAN

30

Home Network Categories

Computers (desktop PC PDA shared peripherals) Entertainment (TV DVD VCR camera stereo MP3) Telecomm (telephone cell phone intercom fax) Appliances (microwave fridge clock furnace airco

light) Telemetry (utility meter smokeburglar alarm babycam)

31

Fundamentally different properties

1 Devices have to be easy to install

2 The network and devices have to be foolproof in

operation

3 Low price is essential

4 The network needs sufficient capacity ( for multimedia

application)

5 The network interface and wiring have to be stable for

many years

6 Security and reliability will be very important

(minimize false alarm or misalarm) Home networks may be wired or wireless

32

Internetworks

bull Internetworks connect networks with different hardware

and softwarebull A collection of interconnected networks is called

an internetwork or internetbull Internet is one specific internetbull Gateways are used to make the connection and to

provide the necessary translation (protocol convertion)

33

Network Software

bull Protocol Hierarchies (Layer structure)bull Design Issues for the Layersbull Connection-Oriented and Connectionless Servicesbull Service Primitivesbull The Relationship of Services to Protocols

34

Network Software

Protocol Hierarchiesndash a series of layers (levels)

ndash lower layer provides service to higher layers

ndash protocol bull an agreement between the communication parties on how

communication is to proceed

ndash Peers bull the corresponding layers on different machines

ndash Network architecture a set of layers and protocols

ndash Protocol stack bull a list of protocols used by a certain system one protocol per

layer

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
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  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

9

Business Applications of Networks (2)

The client-server model involves requests and replies

a Two processes are involved

b A communication network is needed

10

Home Network Applications

bull Access to remote information

bull Person-to-person communication

bull Interactive entertainment

bull Electronic commerce

11

Networks for Peoplendash Access to remote information

bull eg financial shopping customized newspapers on-line digital library WWW

ndash Person-to-person communicationbull email video conference newsgroup

ndash Interactive entertainmentbull VOD interactive movies or TVs game playing

12

Home Network Applications (2)

In peer-to-peer system there are no fixed clients and servers

13

Home Network Applications (3)

Some forms of e-commerce

14

Mobile Network Users

Combinations of wireless networks and mobile computing

mobile-commerce

15

Social Issues

bull Politics

bull Religion

bull Sex

bull Privacy

bull Crime

bull junk mail ill-information Each country has different laws Debate rages

16

Network Hardware

bull Local Area Networks

bull Metropolitan Area Networks

bull Wide Area Networks

bull Wireless Networks

bull Home Networks

bull Internetworks

17

Types of transmission technology

bull Broadcast links

bull Point-to-point links

Network Hardware

18

Network Hardwarendash Broadcast networks

bull single communication channel shared by all machines

bull broadcasting or multicasting (via packets)ndash broadcasting a special code in address field

ndash multicasting reserve one bit to indicate multicasting the remaining n-1address bits can hold a group number Each machine can subscribe to any groups

bull used by localized networks (or satellites)

ndash point-to-point networksbull many hops

bull routing algorithms multiple routs are possible

bull used by large networks

19

Classification of interconnected processors by scale

20

Local Area Networks (LANs)

Two broadcast networks(a) Bus(b) Ring

middot Characterics of LANs (a) privated-owned (b) small size (c) transmission technology (d) topology

middot Ethernets are most popular (up to 10 Gbs)

21

Local Area Networks Characteristics

ndash small size

ndash transmission technologybull single cable

bull 10Mbps ~ 10Gbs

bull 10Gbs 10000000000 bps

ndash topology

bull bus

ndash Ethernet (IEEE 8023) 10 or 100 Mbps (10Gbs)

bull ring

ndash IBM token ring (IEEE 8025) 4 or 16 Mbps

Channel allocation of broadcast networksndash static each machine has an allocated time slot

ndash dynamic

22

Metropolitan Area Networks

A metropolitan area network based on cable TV

23

Wide Area Networks (WANs)

Relation between hosts on LANs and the subnet

middotWANs are point-to-point networks

middotWANs consist of two distinct components transmission lines (copper fiber microwave) and switches (electronics optics)

Store-and-forward or packet-switched subnet

24

Network Topology

25

Subnet (WANs)Subnet (WANs) is consists of two components

ndash transmission lines (circuits channels trunks)bull move bits between machines

ndash switching elementsbull connect transmission lines

bull Router also called packet switching nodes intermediate systems and data switching exchanges

bull Operate in store-and-forward or packet-switched mode

26

Wide Area Networks (2)

A stream of packets from sender to receiver (virtual- circuit)

Routing decisions are made locallymiddot How A makes that decision is called the routing algorithm Will be studied in detail in Chapter 5

917 End

27

Wireless Networks

Categories of wireless networksbull System interconnection

(short-range radio eg Bluetooth)bull Wireless LANs

(80211a 80211b 80211g)bull Wireless WANs

(80216 Cellular telephones Satellites)bull Wireless sensor networks

28

Wireless Networks (2)

(a) Bluetooth configuration(b) Wireless LAN

29

Wireless Networks (3)

(a) Individual mobile computers(b) A flying LAN

30

Home Network Categories

Computers (desktop PC PDA shared peripherals) Entertainment (TV DVD VCR camera stereo MP3) Telecomm (telephone cell phone intercom fax) Appliances (microwave fridge clock furnace airco

light) Telemetry (utility meter smokeburglar alarm babycam)

31

Fundamentally different properties

1 Devices have to be easy to install

2 The network and devices have to be foolproof in

operation

3 Low price is essential

4 The network needs sufficient capacity ( for multimedia

application)

5 The network interface and wiring have to be stable for

many years

6 Security and reliability will be very important

(minimize false alarm or misalarm) Home networks may be wired or wireless

32

Internetworks

bull Internetworks connect networks with different hardware

and softwarebull A collection of interconnected networks is called

an internetwork or internetbull Internet is one specific internetbull Gateways are used to make the connection and to

provide the necessary translation (protocol convertion)

33

Network Software

bull Protocol Hierarchies (Layer structure)bull Design Issues for the Layersbull Connection-Oriented and Connectionless Servicesbull Service Primitivesbull The Relationship of Services to Protocols

34

Network Software

Protocol Hierarchiesndash a series of layers (levels)

ndash lower layer provides service to higher layers

ndash protocol bull an agreement between the communication parties on how

communication is to proceed

ndash Peers bull the corresponding layers on different machines

ndash Network architecture a set of layers and protocols

ndash Protocol stack bull a list of protocols used by a certain system one protocol per

layer

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
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  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

10

Home Network Applications

bull Access to remote information

bull Person-to-person communication

bull Interactive entertainment

bull Electronic commerce

11

Networks for Peoplendash Access to remote information

bull eg financial shopping customized newspapers on-line digital library WWW

ndash Person-to-person communicationbull email video conference newsgroup

ndash Interactive entertainmentbull VOD interactive movies or TVs game playing

12

Home Network Applications (2)

In peer-to-peer system there are no fixed clients and servers

13

Home Network Applications (3)

Some forms of e-commerce

14

Mobile Network Users

Combinations of wireless networks and mobile computing

mobile-commerce

15

Social Issues

bull Politics

bull Religion

bull Sex

bull Privacy

bull Crime

bull junk mail ill-information Each country has different laws Debate rages

16

Network Hardware

bull Local Area Networks

bull Metropolitan Area Networks

bull Wide Area Networks

bull Wireless Networks

bull Home Networks

bull Internetworks

17

Types of transmission technology

bull Broadcast links

bull Point-to-point links

Network Hardware

18

Network Hardwarendash Broadcast networks

bull single communication channel shared by all machines

bull broadcasting or multicasting (via packets)ndash broadcasting a special code in address field

ndash multicasting reserve one bit to indicate multicasting the remaining n-1address bits can hold a group number Each machine can subscribe to any groups

bull used by localized networks (or satellites)

ndash point-to-point networksbull many hops

bull routing algorithms multiple routs are possible

bull used by large networks

19

Classification of interconnected processors by scale

20

Local Area Networks (LANs)

Two broadcast networks(a) Bus(b) Ring

middot Characterics of LANs (a) privated-owned (b) small size (c) transmission technology (d) topology

middot Ethernets are most popular (up to 10 Gbs)

21

Local Area Networks Characteristics

ndash small size

ndash transmission technologybull single cable

bull 10Mbps ~ 10Gbs

bull 10Gbs 10000000000 bps

ndash topology

bull bus

ndash Ethernet (IEEE 8023) 10 or 100 Mbps (10Gbs)

bull ring

ndash IBM token ring (IEEE 8025) 4 or 16 Mbps

Channel allocation of broadcast networksndash static each machine has an allocated time slot

ndash dynamic

22

Metropolitan Area Networks

A metropolitan area network based on cable TV

23

Wide Area Networks (WANs)

Relation between hosts on LANs and the subnet

middotWANs are point-to-point networks

middotWANs consist of two distinct components transmission lines (copper fiber microwave) and switches (electronics optics)

Store-and-forward or packet-switched subnet

24

Network Topology

25

Subnet (WANs)Subnet (WANs) is consists of two components

ndash transmission lines (circuits channels trunks)bull move bits between machines

ndash switching elementsbull connect transmission lines

bull Router also called packet switching nodes intermediate systems and data switching exchanges

bull Operate in store-and-forward or packet-switched mode

26

Wide Area Networks (2)

A stream of packets from sender to receiver (virtual- circuit)

Routing decisions are made locallymiddot How A makes that decision is called the routing algorithm Will be studied in detail in Chapter 5

917 End

27

Wireless Networks

Categories of wireless networksbull System interconnection

(short-range radio eg Bluetooth)bull Wireless LANs

(80211a 80211b 80211g)bull Wireless WANs

(80216 Cellular telephones Satellites)bull Wireless sensor networks

28

Wireless Networks (2)

(a) Bluetooth configuration(b) Wireless LAN

29

Wireless Networks (3)

(a) Individual mobile computers(b) A flying LAN

30

Home Network Categories

Computers (desktop PC PDA shared peripherals) Entertainment (TV DVD VCR camera stereo MP3) Telecomm (telephone cell phone intercom fax) Appliances (microwave fridge clock furnace airco

light) Telemetry (utility meter smokeburglar alarm babycam)

31

Fundamentally different properties

1 Devices have to be easy to install

2 The network and devices have to be foolproof in

operation

3 Low price is essential

4 The network needs sufficient capacity ( for multimedia

application)

5 The network interface and wiring have to be stable for

many years

6 Security and reliability will be very important

(minimize false alarm or misalarm) Home networks may be wired or wireless

32

Internetworks

bull Internetworks connect networks with different hardware

and softwarebull A collection of interconnected networks is called

an internetwork or internetbull Internet is one specific internetbull Gateways are used to make the connection and to

provide the necessary translation (protocol convertion)

33

Network Software

bull Protocol Hierarchies (Layer structure)bull Design Issues for the Layersbull Connection-Oriented and Connectionless Servicesbull Service Primitivesbull The Relationship of Services to Protocols

34

Network Software

Protocol Hierarchiesndash a series of layers (levels)

ndash lower layer provides service to higher layers

ndash protocol bull an agreement between the communication parties on how

communication is to proceed

ndash Peers bull the corresponding layers on different machines

ndash Network architecture a set of layers and protocols

ndash Protocol stack bull a list of protocols used by a certain system one protocol per

layer

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
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  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

11

Networks for Peoplendash Access to remote information

bull eg financial shopping customized newspapers on-line digital library WWW

ndash Person-to-person communicationbull email video conference newsgroup

ndash Interactive entertainmentbull VOD interactive movies or TVs game playing

12

Home Network Applications (2)

In peer-to-peer system there are no fixed clients and servers

13

Home Network Applications (3)

Some forms of e-commerce

14

Mobile Network Users

Combinations of wireless networks and mobile computing

mobile-commerce

15

Social Issues

bull Politics

bull Religion

bull Sex

bull Privacy

bull Crime

bull junk mail ill-information Each country has different laws Debate rages

16

Network Hardware

bull Local Area Networks

bull Metropolitan Area Networks

bull Wide Area Networks

bull Wireless Networks

bull Home Networks

bull Internetworks

17

Types of transmission technology

bull Broadcast links

bull Point-to-point links

Network Hardware

18

Network Hardwarendash Broadcast networks

bull single communication channel shared by all machines

bull broadcasting or multicasting (via packets)ndash broadcasting a special code in address field

ndash multicasting reserve one bit to indicate multicasting the remaining n-1address bits can hold a group number Each machine can subscribe to any groups

bull used by localized networks (or satellites)

ndash point-to-point networksbull many hops

bull routing algorithms multiple routs are possible

bull used by large networks

19

Classification of interconnected processors by scale

20

Local Area Networks (LANs)

Two broadcast networks(a) Bus(b) Ring

middot Characterics of LANs (a) privated-owned (b) small size (c) transmission technology (d) topology

middot Ethernets are most popular (up to 10 Gbs)

21

Local Area Networks Characteristics

ndash small size

ndash transmission technologybull single cable

bull 10Mbps ~ 10Gbs

bull 10Gbs 10000000000 bps

ndash topology

bull bus

ndash Ethernet (IEEE 8023) 10 or 100 Mbps (10Gbs)

bull ring

ndash IBM token ring (IEEE 8025) 4 or 16 Mbps

Channel allocation of broadcast networksndash static each machine has an allocated time slot

ndash dynamic

22

Metropolitan Area Networks

A metropolitan area network based on cable TV

23

Wide Area Networks (WANs)

Relation between hosts on LANs and the subnet

middotWANs are point-to-point networks

middotWANs consist of two distinct components transmission lines (copper fiber microwave) and switches (electronics optics)

Store-and-forward or packet-switched subnet

24

Network Topology

25

Subnet (WANs)Subnet (WANs) is consists of two components

ndash transmission lines (circuits channels trunks)bull move bits between machines

ndash switching elementsbull connect transmission lines

bull Router also called packet switching nodes intermediate systems and data switching exchanges

bull Operate in store-and-forward or packet-switched mode

26

Wide Area Networks (2)

A stream of packets from sender to receiver (virtual- circuit)

Routing decisions are made locallymiddot How A makes that decision is called the routing algorithm Will be studied in detail in Chapter 5

917 End

27

Wireless Networks

Categories of wireless networksbull System interconnection

(short-range radio eg Bluetooth)bull Wireless LANs

(80211a 80211b 80211g)bull Wireless WANs

(80216 Cellular telephones Satellites)bull Wireless sensor networks

28

Wireless Networks (2)

(a) Bluetooth configuration(b) Wireless LAN

29

Wireless Networks (3)

(a) Individual mobile computers(b) A flying LAN

30

Home Network Categories

Computers (desktop PC PDA shared peripherals) Entertainment (TV DVD VCR camera stereo MP3) Telecomm (telephone cell phone intercom fax) Appliances (microwave fridge clock furnace airco

light) Telemetry (utility meter smokeburglar alarm babycam)

31

Fundamentally different properties

1 Devices have to be easy to install

2 The network and devices have to be foolproof in

operation

3 Low price is essential

4 The network needs sufficient capacity ( for multimedia

application)

5 The network interface and wiring have to be stable for

many years

6 Security and reliability will be very important

(minimize false alarm or misalarm) Home networks may be wired or wireless

32

Internetworks

bull Internetworks connect networks with different hardware

and softwarebull A collection of interconnected networks is called

an internetwork or internetbull Internet is one specific internetbull Gateways are used to make the connection and to

provide the necessary translation (protocol convertion)

33

Network Software

bull Protocol Hierarchies (Layer structure)bull Design Issues for the Layersbull Connection-Oriented and Connectionless Servicesbull Service Primitivesbull The Relationship of Services to Protocols

34

Network Software

Protocol Hierarchiesndash a series of layers (levels)

ndash lower layer provides service to higher layers

ndash protocol bull an agreement between the communication parties on how

communication is to proceed

ndash Peers bull the corresponding layers on different machines

ndash Network architecture a set of layers and protocols

ndash Protocol stack bull a list of protocols used by a certain system one protocol per

layer

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
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  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

12

Home Network Applications (2)

In peer-to-peer system there are no fixed clients and servers

13

Home Network Applications (3)

Some forms of e-commerce

14

Mobile Network Users

Combinations of wireless networks and mobile computing

mobile-commerce

15

Social Issues

bull Politics

bull Religion

bull Sex

bull Privacy

bull Crime

bull junk mail ill-information Each country has different laws Debate rages

16

Network Hardware

bull Local Area Networks

bull Metropolitan Area Networks

bull Wide Area Networks

bull Wireless Networks

bull Home Networks

bull Internetworks

17

Types of transmission technology

bull Broadcast links

bull Point-to-point links

Network Hardware

18

Network Hardwarendash Broadcast networks

bull single communication channel shared by all machines

bull broadcasting or multicasting (via packets)ndash broadcasting a special code in address field

ndash multicasting reserve one bit to indicate multicasting the remaining n-1address bits can hold a group number Each machine can subscribe to any groups

bull used by localized networks (or satellites)

ndash point-to-point networksbull many hops

bull routing algorithms multiple routs are possible

bull used by large networks

19

Classification of interconnected processors by scale

20

Local Area Networks (LANs)

Two broadcast networks(a) Bus(b) Ring

middot Characterics of LANs (a) privated-owned (b) small size (c) transmission technology (d) topology

middot Ethernets are most popular (up to 10 Gbs)

21

Local Area Networks Characteristics

ndash small size

ndash transmission technologybull single cable

bull 10Mbps ~ 10Gbs

bull 10Gbs 10000000000 bps

ndash topology

bull bus

ndash Ethernet (IEEE 8023) 10 or 100 Mbps (10Gbs)

bull ring

ndash IBM token ring (IEEE 8025) 4 or 16 Mbps

Channel allocation of broadcast networksndash static each machine has an allocated time slot

ndash dynamic

22

Metropolitan Area Networks

A metropolitan area network based on cable TV

23

Wide Area Networks (WANs)

Relation between hosts on LANs and the subnet

middotWANs are point-to-point networks

middotWANs consist of two distinct components transmission lines (copper fiber microwave) and switches (electronics optics)

Store-and-forward or packet-switched subnet

24

Network Topology

25

Subnet (WANs)Subnet (WANs) is consists of two components

ndash transmission lines (circuits channels trunks)bull move bits between machines

ndash switching elementsbull connect transmission lines

bull Router also called packet switching nodes intermediate systems and data switching exchanges

bull Operate in store-and-forward or packet-switched mode

26

Wide Area Networks (2)

A stream of packets from sender to receiver (virtual- circuit)

Routing decisions are made locallymiddot How A makes that decision is called the routing algorithm Will be studied in detail in Chapter 5

917 End

27

Wireless Networks

Categories of wireless networksbull System interconnection

(short-range radio eg Bluetooth)bull Wireless LANs

(80211a 80211b 80211g)bull Wireless WANs

(80216 Cellular telephones Satellites)bull Wireless sensor networks

28

Wireless Networks (2)

(a) Bluetooth configuration(b) Wireless LAN

29

Wireless Networks (3)

(a) Individual mobile computers(b) A flying LAN

30

Home Network Categories

Computers (desktop PC PDA shared peripherals) Entertainment (TV DVD VCR camera stereo MP3) Telecomm (telephone cell phone intercom fax) Appliances (microwave fridge clock furnace airco

light) Telemetry (utility meter smokeburglar alarm babycam)

31

Fundamentally different properties

1 Devices have to be easy to install

2 The network and devices have to be foolproof in

operation

3 Low price is essential

4 The network needs sufficient capacity ( for multimedia

application)

5 The network interface and wiring have to be stable for

many years

6 Security and reliability will be very important

(minimize false alarm or misalarm) Home networks may be wired or wireless

32

Internetworks

bull Internetworks connect networks with different hardware

and softwarebull A collection of interconnected networks is called

an internetwork or internetbull Internet is one specific internetbull Gateways are used to make the connection and to

provide the necessary translation (protocol convertion)

33

Network Software

bull Protocol Hierarchies (Layer structure)bull Design Issues for the Layersbull Connection-Oriented and Connectionless Servicesbull Service Primitivesbull The Relationship of Services to Protocols

34

Network Software

Protocol Hierarchiesndash a series of layers (levels)

ndash lower layer provides service to higher layers

ndash protocol bull an agreement between the communication parties on how

communication is to proceed

ndash Peers bull the corresponding layers on different machines

ndash Network architecture a set of layers and protocols

ndash Protocol stack bull a list of protocols used by a certain system one protocol per

layer

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
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  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

13

Home Network Applications (3)

Some forms of e-commerce

14

Mobile Network Users

Combinations of wireless networks and mobile computing

mobile-commerce

15

Social Issues

bull Politics

bull Religion

bull Sex

bull Privacy

bull Crime

bull junk mail ill-information Each country has different laws Debate rages

16

Network Hardware

bull Local Area Networks

bull Metropolitan Area Networks

bull Wide Area Networks

bull Wireless Networks

bull Home Networks

bull Internetworks

17

Types of transmission technology

bull Broadcast links

bull Point-to-point links

Network Hardware

18

Network Hardwarendash Broadcast networks

bull single communication channel shared by all machines

bull broadcasting or multicasting (via packets)ndash broadcasting a special code in address field

ndash multicasting reserve one bit to indicate multicasting the remaining n-1address bits can hold a group number Each machine can subscribe to any groups

bull used by localized networks (or satellites)

ndash point-to-point networksbull many hops

bull routing algorithms multiple routs are possible

bull used by large networks

19

Classification of interconnected processors by scale

20

Local Area Networks (LANs)

Two broadcast networks(a) Bus(b) Ring

middot Characterics of LANs (a) privated-owned (b) small size (c) transmission technology (d) topology

middot Ethernets are most popular (up to 10 Gbs)

21

Local Area Networks Characteristics

ndash small size

ndash transmission technologybull single cable

bull 10Mbps ~ 10Gbs

bull 10Gbs 10000000000 bps

ndash topology

bull bus

ndash Ethernet (IEEE 8023) 10 or 100 Mbps (10Gbs)

bull ring

ndash IBM token ring (IEEE 8025) 4 or 16 Mbps

Channel allocation of broadcast networksndash static each machine has an allocated time slot

ndash dynamic

22

Metropolitan Area Networks

A metropolitan area network based on cable TV

23

Wide Area Networks (WANs)

Relation between hosts on LANs and the subnet

middotWANs are point-to-point networks

middotWANs consist of two distinct components transmission lines (copper fiber microwave) and switches (electronics optics)

Store-and-forward or packet-switched subnet

24

Network Topology

25

Subnet (WANs)Subnet (WANs) is consists of two components

ndash transmission lines (circuits channels trunks)bull move bits between machines

ndash switching elementsbull connect transmission lines

bull Router also called packet switching nodes intermediate systems and data switching exchanges

bull Operate in store-and-forward or packet-switched mode

26

Wide Area Networks (2)

A stream of packets from sender to receiver (virtual- circuit)

Routing decisions are made locallymiddot How A makes that decision is called the routing algorithm Will be studied in detail in Chapter 5

917 End

27

Wireless Networks

Categories of wireless networksbull System interconnection

(short-range radio eg Bluetooth)bull Wireless LANs

(80211a 80211b 80211g)bull Wireless WANs

(80216 Cellular telephones Satellites)bull Wireless sensor networks

28

Wireless Networks (2)

(a) Bluetooth configuration(b) Wireless LAN

29

Wireless Networks (3)

(a) Individual mobile computers(b) A flying LAN

30

Home Network Categories

Computers (desktop PC PDA shared peripherals) Entertainment (TV DVD VCR camera stereo MP3) Telecomm (telephone cell phone intercom fax) Appliances (microwave fridge clock furnace airco

light) Telemetry (utility meter smokeburglar alarm babycam)

31

Fundamentally different properties

1 Devices have to be easy to install

2 The network and devices have to be foolproof in

operation

3 Low price is essential

4 The network needs sufficient capacity ( for multimedia

application)

5 The network interface and wiring have to be stable for

many years

6 Security and reliability will be very important

(minimize false alarm or misalarm) Home networks may be wired or wireless

32

Internetworks

bull Internetworks connect networks with different hardware

and softwarebull A collection of interconnected networks is called

an internetwork or internetbull Internet is one specific internetbull Gateways are used to make the connection and to

provide the necessary translation (protocol convertion)

33

Network Software

bull Protocol Hierarchies (Layer structure)bull Design Issues for the Layersbull Connection-Oriented and Connectionless Servicesbull Service Primitivesbull The Relationship of Services to Protocols

34

Network Software

Protocol Hierarchiesndash a series of layers (levels)

ndash lower layer provides service to higher layers

ndash protocol bull an agreement between the communication parties on how

communication is to proceed

ndash Peers bull the corresponding layers on different machines

ndash Network architecture a set of layers and protocols

ndash Protocol stack bull a list of protocols used by a certain system one protocol per

layer

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
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  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

14

Mobile Network Users

Combinations of wireless networks and mobile computing

mobile-commerce

15

Social Issues

bull Politics

bull Religion

bull Sex

bull Privacy

bull Crime

bull junk mail ill-information Each country has different laws Debate rages

16

Network Hardware

bull Local Area Networks

bull Metropolitan Area Networks

bull Wide Area Networks

bull Wireless Networks

bull Home Networks

bull Internetworks

17

Types of transmission technology

bull Broadcast links

bull Point-to-point links

Network Hardware

18

Network Hardwarendash Broadcast networks

bull single communication channel shared by all machines

bull broadcasting or multicasting (via packets)ndash broadcasting a special code in address field

ndash multicasting reserve one bit to indicate multicasting the remaining n-1address bits can hold a group number Each machine can subscribe to any groups

bull used by localized networks (or satellites)

ndash point-to-point networksbull many hops

bull routing algorithms multiple routs are possible

bull used by large networks

19

Classification of interconnected processors by scale

20

Local Area Networks (LANs)

Two broadcast networks(a) Bus(b) Ring

middot Characterics of LANs (a) privated-owned (b) small size (c) transmission technology (d) topology

middot Ethernets are most popular (up to 10 Gbs)

21

Local Area Networks Characteristics

ndash small size

ndash transmission technologybull single cable

bull 10Mbps ~ 10Gbs

bull 10Gbs 10000000000 bps

ndash topology

bull bus

ndash Ethernet (IEEE 8023) 10 or 100 Mbps (10Gbs)

bull ring

ndash IBM token ring (IEEE 8025) 4 or 16 Mbps

Channel allocation of broadcast networksndash static each machine has an allocated time slot

ndash dynamic

22

Metropolitan Area Networks

A metropolitan area network based on cable TV

23

Wide Area Networks (WANs)

Relation between hosts on LANs and the subnet

middotWANs are point-to-point networks

middotWANs consist of two distinct components transmission lines (copper fiber microwave) and switches (electronics optics)

Store-and-forward or packet-switched subnet

24

Network Topology

25

Subnet (WANs)Subnet (WANs) is consists of two components

ndash transmission lines (circuits channels trunks)bull move bits between machines

ndash switching elementsbull connect transmission lines

bull Router also called packet switching nodes intermediate systems and data switching exchanges

bull Operate in store-and-forward or packet-switched mode

26

Wide Area Networks (2)

A stream of packets from sender to receiver (virtual- circuit)

Routing decisions are made locallymiddot How A makes that decision is called the routing algorithm Will be studied in detail in Chapter 5

917 End

27

Wireless Networks

Categories of wireless networksbull System interconnection

(short-range radio eg Bluetooth)bull Wireless LANs

(80211a 80211b 80211g)bull Wireless WANs

(80216 Cellular telephones Satellites)bull Wireless sensor networks

28

Wireless Networks (2)

(a) Bluetooth configuration(b) Wireless LAN

29

Wireless Networks (3)

(a) Individual mobile computers(b) A flying LAN

30

Home Network Categories

Computers (desktop PC PDA shared peripherals) Entertainment (TV DVD VCR camera stereo MP3) Telecomm (telephone cell phone intercom fax) Appliances (microwave fridge clock furnace airco

light) Telemetry (utility meter smokeburglar alarm babycam)

31

Fundamentally different properties

1 Devices have to be easy to install

2 The network and devices have to be foolproof in

operation

3 Low price is essential

4 The network needs sufficient capacity ( for multimedia

application)

5 The network interface and wiring have to be stable for

many years

6 Security and reliability will be very important

(minimize false alarm or misalarm) Home networks may be wired or wireless

32

Internetworks

bull Internetworks connect networks with different hardware

and softwarebull A collection of interconnected networks is called

an internetwork or internetbull Internet is one specific internetbull Gateways are used to make the connection and to

provide the necessary translation (protocol convertion)

33

Network Software

bull Protocol Hierarchies (Layer structure)bull Design Issues for the Layersbull Connection-Oriented and Connectionless Servicesbull Service Primitivesbull The Relationship of Services to Protocols

34

Network Software

Protocol Hierarchiesndash a series of layers (levels)

ndash lower layer provides service to higher layers

ndash protocol bull an agreement between the communication parties on how

communication is to proceed

ndash Peers bull the corresponding layers on different machines

ndash Network architecture a set of layers and protocols

ndash Protocol stack bull a list of protocols used by a certain system one protocol per

layer

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
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  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

15

Social Issues

bull Politics

bull Religion

bull Sex

bull Privacy

bull Crime

bull junk mail ill-information Each country has different laws Debate rages

16

Network Hardware

bull Local Area Networks

bull Metropolitan Area Networks

bull Wide Area Networks

bull Wireless Networks

bull Home Networks

bull Internetworks

17

Types of transmission technology

bull Broadcast links

bull Point-to-point links

Network Hardware

18

Network Hardwarendash Broadcast networks

bull single communication channel shared by all machines

bull broadcasting or multicasting (via packets)ndash broadcasting a special code in address field

ndash multicasting reserve one bit to indicate multicasting the remaining n-1address bits can hold a group number Each machine can subscribe to any groups

bull used by localized networks (or satellites)

ndash point-to-point networksbull many hops

bull routing algorithms multiple routs are possible

bull used by large networks

19

Classification of interconnected processors by scale

20

Local Area Networks (LANs)

Two broadcast networks(a) Bus(b) Ring

middot Characterics of LANs (a) privated-owned (b) small size (c) transmission technology (d) topology

middot Ethernets are most popular (up to 10 Gbs)

21

Local Area Networks Characteristics

ndash small size

ndash transmission technologybull single cable

bull 10Mbps ~ 10Gbs

bull 10Gbs 10000000000 bps

ndash topology

bull bus

ndash Ethernet (IEEE 8023) 10 or 100 Mbps (10Gbs)

bull ring

ndash IBM token ring (IEEE 8025) 4 or 16 Mbps

Channel allocation of broadcast networksndash static each machine has an allocated time slot

ndash dynamic

22

Metropolitan Area Networks

A metropolitan area network based on cable TV

23

Wide Area Networks (WANs)

Relation between hosts on LANs and the subnet

middotWANs are point-to-point networks

middotWANs consist of two distinct components transmission lines (copper fiber microwave) and switches (electronics optics)

Store-and-forward or packet-switched subnet

24

Network Topology

25

Subnet (WANs)Subnet (WANs) is consists of two components

ndash transmission lines (circuits channels trunks)bull move bits between machines

ndash switching elementsbull connect transmission lines

bull Router also called packet switching nodes intermediate systems and data switching exchanges

bull Operate in store-and-forward or packet-switched mode

26

Wide Area Networks (2)

A stream of packets from sender to receiver (virtual- circuit)

Routing decisions are made locallymiddot How A makes that decision is called the routing algorithm Will be studied in detail in Chapter 5

917 End

27

Wireless Networks

Categories of wireless networksbull System interconnection

(short-range radio eg Bluetooth)bull Wireless LANs

(80211a 80211b 80211g)bull Wireless WANs

(80216 Cellular telephones Satellites)bull Wireless sensor networks

28

Wireless Networks (2)

(a) Bluetooth configuration(b) Wireless LAN

29

Wireless Networks (3)

(a) Individual mobile computers(b) A flying LAN

30

Home Network Categories

Computers (desktop PC PDA shared peripherals) Entertainment (TV DVD VCR camera stereo MP3) Telecomm (telephone cell phone intercom fax) Appliances (microwave fridge clock furnace airco

light) Telemetry (utility meter smokeburglar alarm babycam)

31

Fundamentally different properties

1 Devices have to be easy to install

2 The network and devices have to be foolproof in

operation

3 Low price is essential

4 The network needs sufficient capacity ( for multimedia

application)

5 The network interface and wiring have to be stable for

many years

6 Security and reliability will be very important

(minimize false alarm or misalarm) Home networks may be wired or wireless

32

Internetworks

bull Internetworks connect networks with different hardware

and softwarebull A collection of interconnected networks is called

an internetwork or internetbull Internet is one specific internetbull Gateways are used to make the connection and to

provide the necessary translation (protocol convertion)

33

Network Software

bull Protocol Hierarchies (Layer structure)bull Design Issues for the Layersbull Connection-Oriented and Connectionless Servicesbull Service Primitivesbull The Relationship of Services to Protocols

34

Network Software

Protocol Hierarchiesndash a series of layers (levels)

ndash lower layer provides service to higher layers

ndash protocol bull an agreement between the communication parties on how

communication is to proceed

ndash Peers bull the corresponding layers on different machines

ndash Network architecture a set of layers and protocols

ndash Protocol stack bull a list of protocols used by a certain system one protocol per

layer

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
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  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

16

Network Hardware

bull Local Area Networks

bull Metropolitan Area Networks

bull Wide Area Networks

bull Wireless Networks

bull Home Networks

bull Internetworks

17

Types of transmission technology

bull Broadcast links

bull Point-to-point links

Network Hardware

18

Network Hardwarendash Broadcast networks

bull single communication channel shared by all machines

bull broadcasting or multicasting (via packets)ndash broadcasting a special code in address field

ndash multicasting reserve one bit to indicate multicasting the remaining n-1address bits can hold a group number Each machine can subscribe to any groups

bull used by localized networks (or satellites)

ndash point-to-point networksbull many hops

bull routing algorithms multiple routs are possible

bull used by large networks

19

Classification of interconnected processors by scale

20

Local Area Networks (LANs)

Two broadcast networks(a) Bus(b) Ring

middot Characterics of LANs (a) privated-owned (b) small size (c) transmission technology (d) topology

middot Ethernets are most popular (up to 10 Gbs)

21

Local Area Networks Characteristics

ndash small size

ndash transmission technologybull single cable

bull 10Mbps ~ 10Gbs

bull 10Gbs 10000000000 bps

ndash topology

bull bus

ndash Ethernet (IEEE 8023) 10 or 100 Mbps (10Gbs)

bull ring

ndash IBM token ring (IEEE 8025) 4 or 16 Mbps

Channel allocation of broadcast networksndash static each machine has an allocated time slot

ndash dynamic

22

Metropolitan Area Networks

A metropolitan area network based on cable TV

23

Wide Area Networks (WANs)

Relation between hosts on LANs and the subnet

middotWANs are point-to-point networks

middotWANs consist of two distinct components transmission lines (copper fiber microwave) and switches (electronics optics)

Store-and-forward or packet-switched subnet

24

Network Topology

25

Subnet (WANs)Subnet (WANs) is consists of two components

ndash transmission lines (circuits channels trunks)bull move bits between machines

ndash switching elementsbull connect transmission lines

bull Router also called packet switching nodes intermediate systems and data switching exchanges

bull Operate in store-and-forward or packet-switched mode

26

Wide Area Networks (2)

A stream of packets from sender to receiver (virtual- circuit)

Routing decisions are made locallymiddot How A makes that decision is called the routing algorithm Will be studied in detail in Chapter 5

917 End

27

Wireless Networks

Categories of wireless networksbull System interconnection

(short-range radio eg Bluetooth)bull Wireless LANs

(80211a 80211b 80211g)bull Wireless WANs

(80216 Cellular telephones Satellites)bull Wireless sensor networks

28

Wireless Networks (2)

(a) Bluetooth configuration(b) Wireless LAN

29

Wireless Networks (3)

(a) Individual mobile computers(b) A flying LAN

30

Home Network Categories

Computers (desktop PC PDA shared peripherals) Entertainment (TV DVD VCR camera stereo MP3) Telecomm (telephone cell phone intercom fax) Appliances (microwave fridge clock furnace airco

light) Telemetry (utility meter smokeburglar alarm babycam)

31

Fundamentally different properties

1 Devices have to be easy to install

2 The network and devices have to be foolproof in

operation

3 Low price is essential

4 The network needs sufficient capacity ( for multimedia

application)

5 The network interface and wiring have to be stable for

many years

6 Security and reliability will be very important

(minimize false alarm or misalarm) Home networks may be wired or wireless

32

Internetworks

bull Internetworks connect networks with different hardware

and softwarebull A collection of interconnected networks is called

an internetwork or internetbull Internet is one specific internetbull Gateways are used to make the connection and to

provide the necessary translation (protocol convertion)

33

Network Software

bull Protocol Hierarchies (Layer structure)bull Design Issues for the Layersbull Connection-Oriented and Connectionless Servicesbull Service Primitivesbull The Relationship of Services to Protocols

34

Network Software

Protocol Hierarchiesndash a series of layers (levels)

ndash lower layer provides service to higher layers

ndash protocol bull an agreement between the communication parties on how

communication is to proceed

ndash Peers bull the corresponding layers on different machines

ndash Network architecture a set of layers and protocols

ndash Protocol stack bull a list of protocols used by a certain system one protocol per

layer

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
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  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

17

Types of transmission technology

bull Broadcast links

bull Point-to-point links

Network Hardware

18

Network Hardwarendash Broadcast networks

bull single communication channel shared by all machines

bull broadcasting or multicasting (via packets)ndash broadcasting a special code in address field

ndash multicasting reserve one bit to indicate multicasting the remaining n-1address bits can hold a group number Each machine can subscribe to any groups

bull used by localized networks (or satellites)

ndash point-to-point networksbull many hops

bull routing algorithms multiple routs are possible

bull used by large networks

19

Classification of interconnected processors by scale

20

Local Area Networks (LANs)

Two broadcast networks(a) Bus(b) Ring

middot Characterics of LANs (a) privated-owned (b) small size (c) transmission technology (d) topology

middot Ethernets are most popular (up to 10 Gbs)

21

Local Area Networks Characteristics

ndash small size

ndash transmission technologybull single cable

bull 10Mbps ~ 10Gbs

bull 10Gbs 10000000000 bps

ndash topology

bull bus

ndash Ethernet (IEEE 8023) 10 or 100 Mbps (10Gbs)

bull ring

ndash IBM token ring (IEEE 8025) 4 or 16 Mbps

Channel allocation of broadcast networksndash static each machine has an allocated time slot

ndash dynamic

22

Metropolitan Area Networks

A metropolitan area network based on cable TV

23

Wide Area Networks (WANs)

Relation between hosts on LANs and the subnet

middotWANs are point-to-point networks

middotWANs consist of two distinct components transmission lines (copper fiber microwave) and switches (electronics optics)

Store-and-forward or packet-switched subnet

24

Network Topology

25

Subnet (WANs)Subnet (WANs) is consists of two components

ndash transmission lines (circuits channels trunks)bull move bits between machines

ndash switching elementsbull connect transmission lines

bull Router also called packet switching nodes intermediate systems and data switching exchanges

bull Operate in store-and-forward or packet-switched mode

26

Wide Area Networks (2)

A stream of packets from sender to receiver (virtual- circuit)

Routing decisions are made locallymiddot How A makes that decision is called the routing algorithm Will be studied in detail in Chapter 5

917 End

27

Wireless Networks

Categories of wireless networksbull System interconnection

(short-range radio eg Bluetooth)bull Wireless LANs

(80211a 80211b 80211g)bull Wireless WANs

(80216 Cellular telephones Satellites)bull Wireless sensor networks

28

Wireless Networks (2)

(a) Bluetooth configuration(b) Wireless LAN

29

Wireless Networks (3)

(a) Individual mobile computers(b) A flying LAN

30

Home Network Categories

Computers (desktop PC PDA shared peripherals) Entertainment (TV DVD VCR camera stereo MP3) Telecomm (telephone cell phone intercom fax) Appliances (microwave fridge clock furnace airco

light) Telemetry (utility meter smokeburglar alarm babycam)

31

Fundamentally different properties

1 Devices have to be easy to install

2 The network and devices have to be foolproof in

operation

3 Low price is essential

4 The network needs sufficient capacity ( for multimedia

application)

5 The network interface and wiring have to be stable for

many years

6 Security and reliability will be very important

(minimize false alarm or misalarm) Home networks may be wired or wireless

32

Internetworks

bull Internetworks connect networks with different hardware

and softwarebull A collection of interconnected networks is called

an internetwork or internetbull Internet is one specific internetbull Gateways are used to make the connection and to

provide the necessary translation (protocol convertion)

33

Network Software

bull Protocol Hierarchies (Layer structure)bull Design Issues for the Layersbull Connection-Oriented and Connectionless Servicesbull Service Primitivesbull The Relationship of Services to Protocols

34

Network Software

Protocol Hierarchiesndash a series of layers (levels)

ndash lower layer provides service to higher layers

ndash protocol bull an agreement between the communication parties on how

communication is to proceed

ndash Peers bull the corresponding layers on different machines

ndash Network architecture a set of layers and protocols

ndash Protocol stack bull a list of protocols used by a certain system one protocol per

layer

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
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  • Slide 80
  • Slide 81
  • Slide 82

18

Network Hardwarendash Broadcast networks

bull single communication channel shared by all machines

bull broadcasting or multicasting (via packets)ndash broadcasting a special code in address field

ndash multicasting reserve one bit to indicate multicasting the remaining n-1address bits can hold a group number Each machine can subscribe to any groups

bull used by localized networks (or satellites)

ndash point-to-point networksbull many hops

bull routing algorithms multiple routs are possible

bull used by large networks

19

Classification of interconnected processors by scale

20

Local Area Networks (LANs)

Two broadcast networks(a) Bus(b) Ring

middot Characterics of LANs (a) privated-owned (b) small size (c) transmission technology (d) topology

middot Ethernets are most popular (up to 10 Gbs)

21

Local Area Networks Characteristics

ndash small size

ndash transmission technologybull single cable

bull 10Mbps ~ 10Gbs

bull 10Gbs 10000000000 bps

ndash topology

bull bus

ndash Ethernet (IEEE 8023) 10 or 100 Mbps (10Gbs)

bull ring

ndash IBM token ring (IEEE 8025) 4 or 16 Mbps

Channel allocation of broadcast networksndash static each machine has an allocated time slot

ndash dynamic

22

Metropolitan Area Networks

A metropolitan area network based on cable TV

23

Wide Area Networks (WANs)

Relation between hosts on LANs and the subnet

middotWANs are point-to-point networks

middotWANs consist of two distinct components transmission lines (copper fiber microwave) and switches (electronics optics)

Store-and-forward or packet-switched subnet

24

Network Topology

25

Subnet (WANs)Subnet (WANs) is consists of two components

ndash transmission lines (circuits channels trunks)bull move bits between machines

ndash switching elementsbull connect transmission lines

bull Router also called packet switching nodes intermediate systems and data switching exchanges

bull Operate in store-and-forward or packet-switched mode

26

Wide Area Networks (2)

A stream of packets from sender to receiver (virtual- circuit)

Routing decisions are made locallymiddot How A makes that decision is called the routing algorithm Will be studied in detail in Chapter 5

917 End

27

Wireless Networks

Categories of wireless networksbull System interconnection

(short-range radio eg Bluetooth)bull Wireless LANs

(80211a 80211b 80211g)bull Wireless WANs

(80216 Cellular telephones Satellites)bull Wireless sensor networks

28

Wireless Networks (2)

(a) Bluetooth configuration(b) Wireless LAN

29

Wireless Networks (3)

(a) Individual mobile computers(b) A flying LAN

30

Home Network Categories

Computers (desktop PC PDA shared peripherals) Entertainment (TV DVD VCR camera stereo MP3) Telecomm (telephone cell phone intercom fax) Appliances (microwave fridge clock furnace airco

light) Telemetry (utility meter smokeburglar alarm babycam)

31

Fundamentally different properties

1 Devices have to be easy to install

2 The network and devices have to be foolproof in

operation

3 Low price is essential

4 The network needs sufficient capacity ( for multimedia

application)

5 The network interface and wiring have to be stable for

many years

6 Security and reliability will be very important

(minimize false alarm or misalarm) Home networks may be wired or wireless

32

Internetworks

bull Internetworks connect networks with different hardware

and softwarebull A collection of interconnected networks is called

an internetwork or internetbull Internet is one specific internetbull Gateways are used to make the connection and to

provide the necessary translation (protocol convertion)

33

Network Software

bull Protocol Hierarchies (Layer structure)bull Design Issues for the Layersbull Connection-Oriented and Connectionless Servicesbull Service Primitivesbull The Relationship of Services to Protocols

34

Network Software

Protocol Hierarchiesndash a series of layers (levels)

ndash lower layer provides service to higher layers

ndash protocol bull an agreement between the communication parties on how

communication is to proceed

ndash Peers bull the corresponding layers on different machines

ndash Network architecture a set of layers and protocols

ndash Protocol stack bull a list of protocols used by a certain system one protocol per

layer

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
  • Slide 11
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  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

19

Classification of interconnected processors by scale

20

Local Area Networks (LANs)

Two broadcast networks(a) Bus(b) Ring

middot Characterics of LANs (a) privated-owned (b) small size (c) transmission technology (d) topology

middot Ethernets are most popular (up to 10 Gbs)

21

Local Area Networks Characteristics

ndash small size

ndash transmission technologybull single cable

bull 10Mbps ~ 10Gbs

bull 10Gbs 10000000000 bps

ndash topology

bull bus

ndash Ethernet (IEEE 8023) 10 or 100 Mbps (10Gbs)

bull ring

ndash IBM token ring (IEEE 8025) 4 or 16 Mbps

Channel allocation of broadcast networksndash static each machine has an allocated time slot

ndash dynamic

22

Metropolitan Area Networks

A metropolitan area network based on cable TV

23

Wide Area Networks (WANs)

Relation between hosts on LANs and the subnet

middotWANs are point-to-point networks

middotWANs consist of two distinct components transmission lines (copper fiber microwave) and switches (electronics optics)

Store-and-forward or packet-switched subnet

24

Network Topology

25

Subnet (WANs)Subnet (WANs) is consists of two components

ndash transmission lines (circuits channels trunks)bull move bits between machines

ndash switching elementsbull connect transmission lines

bull Router also called packet switching nodes intermediate systems and data switching exchanges

bull Operate in store-and-forward or packet-switched mode

26

Wide Area Networks (2)

A stream of packets from sender to receiver (virtual- circuit)

Routing decisions are made locallymiddot How A makes that decision is called the routing algorithm Will be studied in detail in Chapter 5

917 End

27

Wireless Networks

Categories of wireless networksbull System interconnection

(short-range radio eg Bluetooth)bull Wireless LANs

(80211a 80211b 80211g)bull Wireless WANs

(80216 Cellular telephones Satellites)bull Wireless sensor networks

28

Wireless Networks (2)

(a) Bluetooth configuration(b) Wireless LAN

29

Wireless Networks (3)

(a) Individual mobile computers(b) A flying LAN

30

Home Network Categories

Computers (desktop PC PDA shared peripherals) Entertainment (TV DVD VCR camera stereo MP3) Telecomm (telephone cell phone intercom fax) Appliances (microwave fridge clock furnace airco

light) Telemetry (utility meter smokeburglar alarm babycam)

31

Fundamentally different properties

1 Devices have to be easy to install

2 The network and devices have to be foolproof in

operation

3 Low price is essential

4 The network needs sufficient capacity ( for multimedia

application)

5 The network interface and wiring have to be stable for

many years

6 Security and reliability will be very important

(minimize false alarm or misalarm) Home networks may be wired or wireless

32

Internetworks

bull Internetworks connect networks with different hardware

and softwarebull A collection of interconnected networks is called

an internetwork or internetbull Internet is one specific internetbull Gateways are used to make the connection and to

provide the necessary translation (protocol convertion)

33

Network Software

bull Protocol Hierarchies (Layer structure)bull Design Issues for the Layersbull Connection-Oriented and Connectionless Servicesbull Service Primitivesbull The Relationship of Services to Protocols

34

Network Software

Protocol Hierarchiesndash a series of layers (levels)

ndash lower layer provides service to higher layers

ndash protocol bull an agreement between the communication parties on how

communication is to proceed

ndash Peers bull the corresponding layers on different machines

ndash Network architecture a set of layers and protocols

ndash Protocol stack bull a list of protocols used by a certain system one protocol per

layer

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
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  • Slide 81
  • Slide 82

20

Local Area Networks (LANs)

Two broadcast networks(a) Bus(b) Ring

middot Characterics of LANs (a) privated-owned (b) small size (c) transmission technology (d) topology

middot Ethernets are most popular (up to 10 Gbs)

21

Local Area Networks Characteristics

ndash small size

ndash transmission technologybull single cable

bull 10Mbps ~ 10Gbs

bull 10Gbs 10000000000 bps

ndash topology

bull bus

ndash Ethernet (IEEE 8023) 10 or 100 Mbps (10Gbs)

bull ring

ndash IBM token ring (IEEE 8025) 4 or 16 Mbps

Channel allocation of broadcast networksndash static each machine has an allocated time slot

ndash dynamic

22

Metropolitan Area Networks

A metropolitan area network based on cable TV

23

Wide Area Networks (WANs)

Relation between hosts on LANs and the subnet

middotWANs are point-to-point networks

middotWANs consist of two distinct components transmission lines (copper fiber microwave) and switches (electronics optics)

Store-and-forward or packet-switched subnet

24

Network Topology

25

Subnet (WANs)Subnet (WANs) is consists of two components

ndash transmission lines (circuits channels trunks)bull move bits between machines

ndash switching elementsbull connect transmission lines

bull Router also called packet switching nodes intermediate systems and data switching exchanges

bull Operate in store-and-forward or packet-switched mode

26

Wide Area Networks (2)

A stream of packets from sender to receiver (virtual- circuit)

Routing decisions are made locallymiddot How A makes that decision is called the routing algorithm Will be studied in detail in Chapter 5

917 End

27

Wireless Networks

Categories of wireless networksbull System interconnection

(short-range radio eg Bluetooth)bull Wireless LANs

(80211a 80211b 80211g)bull Wireless WANs

(80216 Cellular telephones Satellites)bull Wireless sensor networks

28

Wireless Networks (2)

(a) Bluetooth configuration(b) Wireless LAN

29

Wireless Networks (3)

(a) Individual mobile computers(b) A flying LAN

30

Home Network Categories

Computers (desktop PC PDA shared peripherals) Entertainment (TV DVD VCR camera stereo MP3) Telecomm (telephone cell phone intercom fax) Appliances (microwave fridge clock furnace airco

light) Telemetry (utility meter smokeburglar alarm babycam)

31

Fundamentally different properties

1 Devices have to be easy to install

2 The network and devices have to be foolproof in

operation

3 Low price is essential

4 The network needs sufficient capacity ( for multimedia

application)

5 The network interface and wiring have to be stable for

many years

6 Security and reliability will be very important

(minimize false alarm or misalarm) Home networks may be wired or wireless

32

Internetworks

bull Internetworks connect networks with different hardware

and softwarebull A collection of interconnected networks is called

an internetwork or internetbull Internet is one specific internetbull Gateways are used to make the connection and to

provide the necessary translation (protocol convertion)

33

Network Software

bull Protocol Hierarchies (Layer structure)bull Design Issues for the Layersbull Connection-Oriented and Connectionless Servicesbull Service Primitivesbull The Relationship of Services to Protocols

34

Network Software

Protocol Hierarchiesndash a series of layers (levels)

ndash lower layer provides service to higher layers

ndash protocol bull an agreement between the communication parties on how

communication is to proceed

ndash Peers bull the corresponding layers on different machines

ndash Network architecture a set of layers and protocols

ndash Protocol stack bull a list of protocols used by a certain system one protocol per

layer

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
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  • Slide 79
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  • Slide 81
  • Slide 82

21

Local Area Networks Characteristics

ndash small size

ndash transmission technologybull single cable

bull 10Mbps ~ 10Gbs

bull 10Gbs 10000000000 bps

ndash topology

bull bus

ndash Ethernet (IEEE 8023) 10 or 100 Mbps (10Gbs)

bull ring

ndash IBM token ring (IEEE 8025) 4 or 16 Mbps

Channel allocation of broadcast networksndash static each machine has an allocated time slot

ndash dynamic

22

Metropolitan Area Networks

A metropolitan area network based on cable TV

23

Wide Area Networks (WANs)

Relation between hosts on LANs and the subnet

middotWANs are point-to-point networks

middotWANs consist of two distinct components transmission lines (copper fiber microwave) and switches (electronics optics)

Store-and-forward or packet-switched subnet

24

Network Topology

25

Subnet (WANs)Subnet (WANs) is consists of two components

ndash transmission lines (circuits channels trunks)bull move bits between machines

ndash switching elementsbull connect transmission lines

bull Router also called packet switching nodes intermediate systems and data switching exchanges

bull Operate in store-and-forward or packet-switched mode

26

Wide Area Networks (2)

A stream of packets from sender to receiver (virtual- circuit)

Routing decisions are made locallymiddot How A makes that decision is called the routing algorithm Will be studied in detail in Chapter 5

917 End

27

Wireless Networks

Categories of wireless networksbull System interconnection

(short-range radio eg Bluetooth)bull Wireless LANs

(80211a 80211b 80211g)bull Wireless WANs

(80216 Cellular telephones Satellites)bull Wireless sensor networks

28

Wireless Networks (2)

(a) Bluetooth configuration(b) Wireless LAN

29

Wireless Networks (3)

(a) Individual mobile computers(b) A flying LAN

30

Home Network Categories

Computers (desktop PC PDA shared peripherals) Entertainment (TV DVD VCR camera stereo MP3) Telecomm (telephone cell phone intercom fax) Appliances (microwave fridge clock furnace airco

light) Telemetry (utility meter smokeburglar alarm babycam)

31

Fundamentally different properties

1 Devices have to be easy to install

2 The network and devices have to be foolproof in

operation

3 Low price is essential

4 The network needs sufficient capacity ( for multimedia

application)

5 The network interface and wiring have to be stable for

many years

6 Security and reliability will be very important

(minimize false alarm or misalarm) Home networks may be wired or wireless

32

Internetworks

bull Internetworks connect networks with different hardware

and softwarebull A collection of interconnected networks is called

an internetwork or internetbull Internet is one specific internetbull Gateways are used to make the connection and to

provide the necessary translation (protocol convertion)

33

Network Software

bull Protocol Hierarchies (Layer structure)bull Design Issues for the Layersbull Connection-Oriented and Connectionless Servicesbull Service Primitivesbull The Relationship of Services to Protocols

34

Network Software

Protocol Hierarchiesndash a series of layers (levels)

ndash lower layer provides service to higher layers

ndash protocol bull an agreement between the communication parties on how

communication is to proceed

ndash Peers bull the corresponding layers on different machines

ndash Network architecture a set of layers and protocols

ndash Protocol stack bull a list of protocols used by a certain system one protocol per

layer

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
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  • Slide 82

22

Metropolitan Area Networks

A metropolitan area network based on cable TV

23

Wide Area Networks (WANs)

Relation between hosts on LANs and the subnet

middotWANs are point-to-point networks

middotWANs consist of two distinct components transmission lines (copper fiber microwave) and switches (electronics optics)

Store-and-forward or packet-switched subnet

24

Network Topology

25

Subnet (WANs)Subnet (WANs) is consists of two components

ndash transmission lines (circuits channels trunks)bull move bits between machines

ndash switching elementsbull connect transmission lines

bull Router also called packet switching nodes intermediate systems and data switching exchanges

bull Operate in store-and-forward or packet-switched mode

26

Wide Area Networks (2)

A stream of packets from sender to receiver (virtual- circuit)

Routing decisions are made locallymiddot How A makes that decision is called the routing algorithm Will be studied in detail in Chapter 5

917 End

27

Wireless Networks

Categories of wireless networksbull System interconnection

(short-range radio eg Bluetooth)bull Wireless LANs

(80211a 80211b 80211g)bull Wireless WANs

(80216 Cellular telephones Satellites)bull Wireless sensor networks

28

Wireless Networks (2)

(a) Bluetooth configuration(b) Wireless LAN

29

Wireless Networks (3)

(a) Individual mobile computers(b) A flying LAN

30

Home Network Categories

Computers (desktop PC PDA shared peripherals) Entertainment (TV DVD VCR camera stereo MP3) Telecomm (telephone cell phone intercom fax) Appliances (microwave fridge clock furnace airco

light) Telemetry (utility meter smokeburglar alarm babycam)

31

Fundamentally different properties

1 Devices have to be easy to install

2 The network and devices have to be foolproof in

operation

3 Low price is essential

4 The network needs sufficient capacity ( for multimedia

application)

5 The network interface and wiring have to be stable for

many years

6 Security and reliability will be very important

(minimize false alarm or misalarm) Home networks may be wired or wireless

32

Internetworks

bull Internetworks connect networks with different hardware

and softwarebull A collection of interconnected networks is called

an internetwork or internetbull Internet is one specific internetbull Gateways are used to make the connection and to

provide the necessary translation (protocol convertion)

33

Network Software

bull Protocol Hierarchies (Layer structure)bull Design Issues for the Layersbull Connection-Oriented and Connectionless Servicesbull Service Primitivesbull The Relationship of Services to Protocols

34

Network Software

Protocol Hierarchiesndash a series of layers (levels)

ndash lower layer provides service to higher layers

ndash protocol bull an agreement between the communication parties on how

communication is to proceed

ndash Peers bull the corresponding layers on different machines

ndash Network architecture a set of layers and protocols

ndash Protocol stack bull a list of protocols used by a certain system one protocol per

layer

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
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  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

23

Wide Area Networks (WANs)

Relation between hosts on LANs and the subnet

middotWANs are point-to-point networks

middotWANs consist of two distinct components transmission lines (copper fiber microwave) and switches (electronics optics)

Store-and-forward or packet-switched subnet

24

Network Topology

25

Subnet (WANs)Subnet (WANs) is consists of two components

ndash transmission lines (circuits channels trunks)bull move bits between machines

ndash switching elementsbull connect transmission lines

bull Router also called packet switching nodes intermediate systems and data switching exchanges

bull Operate in store-and-forward or packet-switched mode

26

Wide Area Networks (2)

A stream of packets from sender to receiver (virtual- circuit)

Routing decisions are made locallymiddot How A makes that decision is called the routing algorithm Will be studied in detail in Chapter 5

917 End

27

Wireless Networks

Categories of wireless networksbull System interconnection

(short-range radio eg Bluetooth)bull Wireless LANs

(80211a 80211b 80211g)bull Wireless WANs

(80216 Cellular telephones Satellites)bull Wireless sensor networks

28

Wireless Networks (2)

(a) Bluetooth configuration(b) Wireless LAN

29

Wireless Networks (3)

(a) Individual mobile computers(b) A flying LAN

30

Home Network Categories

Computers (desktop PC PDA shared peripherals) Entertainment (TV DVD VCR camera stereo MP3) Telecomm (telephone cell phone intercom fax) Appliances (microwave fridge clock furnace airco

light) Telemetry (utility meter smokeburglar alarm babycam)

31

Fundamentally different properties

1 Devices have to be easy to install

2 The network and devices have to be foolproof in

operation

3 Low price is essential

4 The network needs sufficient capacity ( for multimedia

application)

5 The network interface and wiring have to be stable for

many years

6 Security and reliability will be very important

(minimize false alarm or misalarm) Home networks may be wired or wireless

32

Internetworks

bull Internetworks connect networks with different hardware

and softwarebull A collection of interconnected networks is called

an internetwork or internetbull Internet is one specific internetbull Gateways are used to make the connection and to

provide the necessary translation (protocol convertion)

33

Network Software

bull Protocol Hierarchies (Layer structure)bull Design Issues for the Layersbull Connection-Oriented and Connectionless Servicesbull Service Primitivesbull The Relationship of Services to Protocols

34

Network Software

Protocol Hierarchiesndash a series of layers (levels)

ndash lower layer provides service to higher layers

ndash protocol bull an agreement between the communication parties on how

communication is to proceed

ndash Peers bull the corresponding layers on different machines

ndash Network architecture a set of layers and protocols

ndash Protocol stack bull a list of protocols used by a certain system one protocol per

layer

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
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  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

24

Network Topology

25

Subnet (WANs)Subnet (WANs) is consists of two components

ndash transmission lines (circuits channels trunks)bull move bits between machines

ndash switching elementsbull connect transmission lines

bull Router also called packet switching nodes intermediate systems and data switching exchanges

bull Operate in store-and-forward or packet-switched mode

26

Wide Area Networks (2)

A stream of packets from sender to receiver (virtual- circuit)

Routing decisions are made locallymiddot How A makes that decision is called the routing algorithm Will be studied in detail in Chapter 5

917 End

27

Wireless Networks

Categories of wireless networksbull System interconnection

(short-range radio eg Bluetooth)bull Wireless LANs

(80211a 80211b 80211g)bull Wireless WANs

(80216 Cellular telephones Satellites)bull Wireless sensor networks

28

Wireless Networks (2)

(a) Bluetooth configuration(b) Wireless LAN

29

Wireless Networks (3)

(a) Individual mobile computers(b) A flying LAN

30

Home Network Categories

Computers (desktop PC PDA shared peripherals) Entertainment (TV DVD VCR camera stereo MP3) Telecomm (telephone cell phone intercom fax) Appliances (microwave fridge clock furnace airco

light) Telemetry (utility meter smokeburglar alarm babycam)

31

Fundamentally different properties

1 Devices have to be easy to install

2 The network and devices have to be foolproof in

operation

3 Low price is essential

4 The network needs sufficient capacity ( for multimedia

application)

5 The network interface and wiring have to be stable for

many years

6 Security and reliability will be very important

(minimize false alarm or misalarm) Home networks may be wired or wireless

32

Internetworks

bull Internetworks connect networks with different hardware

and softwarebull A collection of interconnected networks is called

an internetwork or internetbull Internet is one specific internetbull Gateways are used to make the connection and to

provide the necessary translation (protocol convertion)

33

Network Software

bull Protocol Hierarchies (Layer structure)bull Design Issues for the Layersbull Connection-Oriented and Connectionless Servicesbull Service Primitivesbull The Relationship of Services to Protocols

34

Network Software

Protocol Hierarchiesndash a series of layers (levels)

ndash lower layer provides service to higher layers

ndash protocol bull an agreement between the communication parties on how

communication is to proceed

ndash Peers bull the corresponding layers on different machines

ndash Network architecture a set of layers and protocols

ndash Protocol stack bull a list of protocols used by a certain system one protocol per

layer

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
  • Slide 11
  • Slide 12
  • Slide 13
  • Slide 14
  • Slide 15
  • Slide 16
  • Slide 17
  • Slide 18
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  • Slide 64
  • Slide 65
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  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

25

Subnet (WANs)Subnet (WANs) is consists of two components

ndash transmission lines (circuits channels trunks)bull move bits between machines

ndash switching elementsbull connect transmission lines

bull Router also called packet switching nodes intermediate systems and data switching exchanges

bull Operate in store-and-forward or packet-switched mode

26

Wide Area Networks (2)

A stream of packets from sender to receiver (virtual- circuit)

Routing decisions are made locallymiddot How A makes that decision is called the routing algorithm Will be studied in detail in Chapter 5

917 End

27

Wireless Networks

Categories of wireless networksbull System interconnection

(short-range radio eg Bluetooth)bull Wireless LANs

(80211a 80211b 80211g)bull Wireless WANs

(80216 Cellular telephones Satellites)bull Wireless sensor networks

28

Wireless Networks (2)

(a) Bluetooth configuration(b) Wireless LAN

29

Wireless Networks (3)

(a) Individual mobile computers(b) A flying LAN

30

Home Network Categories

Computers (desktop PC PDA shared peripherals) Entertainment (TV DVD VCR camera stereo MP3) Telecomm (telephone cell phone intercom fax) Appliances (microwave fridge clock furnace airco

light) Telemetry (utility meter smokeburglar alarm babycam)

31

Fundamentally different properties

1 Devices have to be easy to install

2 The network and devices have to be foolproof in

operation

3 Low price is essential

4 The network needs sufficient capacity ( for multimedia

application)

5 The network interface and wiring have to be stable for

many years

6 Security and reliability will be very important

(minimize false alarm or misalarm) Home networks may be wired or wireless

32

Internetworks

bull Internetworks connect networks with different hardware

and softwarebull A collection of interconnected networks is called

an internetwork or internetbull Internet is one specific internetbull Gateways are used to make the connection and to

provide the necessary translation (protocol convertion)

33

Network Software

bull Protocol Hierarchies (Layer structure)bull Design Issues for the Layersbull Connection-Oriented and Connectionless Servicesbull Service Primitivesbull The Relationship of Services to Protocols

34

Network Software

Protocol Hierarchiesndash a series of layers (levels)

ndash lower layer provides service to higher layers

ndash protocol bull an agreement between the communication parties on how

communication is to proceed

ndash Peers bull the corresponding layers on different machines

ndash Network architecture a set of layers and protocols

ndash Protocol stack bull a list of protocols used by a certain system one protocol per

layer

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
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  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

26

Wide Area Networks (2)

A stream of packets from sender to receiver (virtual- circuit)

Routing decisions are made locallymiddot How A makes that decision is called the routing algorithm Will be studied in detail in Chapter 5

917 End

27

Wireless Networks

Categories of wireless networksbull System interconnection

(short-range radio eg Bluetooth)bull Wireless LANs

(80211a 80211b 80211g)bull Wireless WANs

(80216 Cellular telephones Satellites)bull Wireless sensor networks

28

Wireless Networks (2)

(a) Bluetooth configuration(b) Wireless LAN

29

Wireless Networks (3)

(a) Individual mobile computers(b) A flying LAN

30

Home Network Categories

Computers (desktop PC PDA shared peripherals) Entertainment (TV DVD VCR camera stereo MP3) Telecomm (telephone cell phone intercom fax) Appliances (microwave fridge clock furnace airco

light) Telemetry (utility meter smokeburglar alarm babycam)

31

Fundamentally different properties

1 Devices have to be easy to install

2 The network and devices have to be foolproof in

operation

3 Low price is essential

4 The network needs sufficient capacity ( for multimedia

application)

5 The network interface and wiring have to be stable for

many years

6 Security and reliability will be very important

(minimize false alarm or misalarm) Home networks may be wired or wireless

32

Internetworks

bull Internetworks connect networks with different hardware

and softwarebull A collection of interconnected networks is called

an internetwork or internetbull Internet is one specific internetbull Gateways are used to make the connection and to

provide the necessary translation (protocol convertion)

33

Network Software

bull Protocol Hierarchies (Layer structure)bull Design Issues for the Layersbull Connection-Oriented and Connectionless Servicesbull Service Primitivesbull The Relationship of Services to Protocols

34

Network Software

Protocol Hierarchiesndash a series of layers (levels)

ndash lower layer provides service to higher layers

ndash protocol bull an agreement between the communication parties on how

communication is to proceed

ndash Peers bull the corresponding layers on different machines

ndash Network architecture a set of layers and protocols

ndash Protocol stack bull a list of protocols used by a certain system one protocol per

layer

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
  • Slide 11
  • Slide 12
  • Slide 13
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  • Slide 35
  • Slide 36
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  • Slide 46
  • Slide 47
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  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

27

Wireless Networks

Categories of wireless networksbull System interconnection

(short-range radio eg Bluetooth)bull Wireless LANs

(80211a 80211b 80211g)bull Wireless WANs

(80216 Cellular telephones Satellites)bull Wireless sensor networks

28

Wireless Networks (2)

(a) Bluetooth configuration(b) Wireless LAN

29

Wireless Networks (3)

(a) Individual mobile computers(b) A flying LAN

30

Home Network Categories

Computers (desktop PC PDA shared peripherals) Entertainment (TV DVD VCR camera stereo MP3) Telecomm (telephone cell phone intercom fax) Appliances (microwave fridge clock furnace airco

light) Telemetry (utility meter smokeburglar alarm babycam)

31

Fundamentally different properties

1 Devices have to be easy to install

2 The network and devices have to be foolproof in

operation

3 Low price is essential

4 The network needs sufficient capacity ( for multimedia

application)

5 The network interface and wiring have to be stable for

many years

6 Security and reliability will be very important

(minimize false alarm or misalarm) Home networks may be wired or wireless

32

Internetworks

bull Internetworks connect networks with different hardware

and softwarebull A collection of interconnected networks is called

an internetwork or internetbull Internet is one specific internetbull Gateways are used to make the connection and to

provide the necessary translation (protocol convertion)

33

Network Software

bull Protocol Hierarchies (Layer structure)bull Design Issues for the Layersbull Connection-Oriented and Connectionless Servicesbull Service Primitivesbull The Relationship of Services to Protocols

34

Network Software

Protocol Hierarchiesndash a series of layers (levels)

ndash lower layer provides service to higher layers

ndash protocol bull an agreement between the communication parties on how

communication is to proceed

ndash Peers bull the corresponding layers on different machines

ndash Network architecture a set of layers and protocols

ndash Protocol stack bull a list of protocols used by a certain system one protocol per

layer

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
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  • Slide 7
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  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

28

Wireless Networks (2)

(a) Bluetooth configuration(b) Wireless LAN

29

Wireless Networks (3)

(a) Individual mobile computers(b) A flying LAN

30

Home Network Categories

Computers (desktop PC PDA shared peripherals) Entertainment (TV DVD VCR camera stereo MP3) Telecomm (telephone cell phone intercom fax) Appliances (microwave fridge clock furnace airco

light) Telemetry (utility meter smokeburglar alarm babycam)

31

Fundamentally different properties

1 Devices have to be easy to install

2 The network and devices have to be foolproof in

operation

3 Low price is essential

4 The network needs sufficient capacity ( for multimedia

application)

5 The network interface and wiring have to be stable for

many years

6 Security and reliability will be very important

(minimize false alarm or misalarm) Home networks may be wired or wireless

32

Internetworks

bull Internetworks connect networks with different hardware

and softwarebull A collection of interconnected networks is called

an internetwork or internetbull Internet is one specific internetbull Gateways are used to make the connection and to

provide the necessary translation (protocol convertion)

33

Network Software

bull Protocol Hierarchies (Layer structure)bull Design Issues for the Layersbull Connection-Oriented and Connectionless Servicesbull Service Primitivesbull The Relationship of Services to Protocols

34

Network Software

Protocol Hierarchiesndash a series of layers (levels)

ndash lower layer provides service to higher layers

ndash protocol bull an agreement between the communication parties on how

communication is to proceed

ndash Peers bull the corresponding layers on different machines

ndash Network architecture a set of layers and protocols

ndash Protocol stack bull a list of protocols used by a certain system one protocol per

layer

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
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  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

29

Wireless Networks (3)

(a) Individual mobile computers(b) A flying LAN

30

Home Network Categories

Computers (desktop PC PDA shared peripherals) Entertainment (TV DVD VCR camera stereo MP3) Telecomm (telephone cell phone intercom fax) Appliances (microwave fridge clock furnace airco

light) Telemetry (utility meter smokeburglar alarm babycam)

31

Fundamentally different properties

1 Devices have to be easy to install

2 The network and devices have to be foolproof in

operation

3 Low price is essential

4 The network needs sufficient capacity ( for multimedia

application)

5 The network interface and wiring have to be stable for

many years

6 Security and reliability will be very important

(minimize false alarm or misalarm) Home networks may be wired or wireless

32

Internetworks

bull Internetworks connect networks with different hardware

and softwarebull A collection of interconnected networks is called

an internetwork or internetbull Internet is one specific internetbull Gateways are used to make the connection and to

provide the necessary translation (protocol convertion)

33

Network Software

bull Protocol Hierarchies (Layer structure)bull Design Issues for the Layersbull Connection-Oriented and Connectionless Servicesbull Service Primitivesbull The Relationship of Services to Protocols

34

Network Software

Protocol Hierarchiesndash a series of layers (levels)

ndash lower layer provides service to higher layers

ndash protocol bull an agreement between the communication parties on how

communication is to proceed

ndash Peers bull the corresponding layers on different machines

ndash Network architecture a set of layers and protocols

ndash Protocol stack bull a list of protocols used by a certain system one protocol per

layer

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
  • Slide 11
  • Slide 12
  • Slide 13
  • Slide 14
  • Slide 15
  • Slide 16
  • Slide 17
  • Slide 18
  • Slide 19
  • Slide 20
  • Slide 21
  • Slide 22
  • Slide 23
  • Slide 24
  • Slide 25
  • Slide 26
  • Slide 27
  • Slide 28
  • Slide 29
  • Slide 30
  • Slide 31
  • Slide 32
  • Slide 33
  • Slide 34
  • Slide 35
  • Slide 36
  • Slide 37
  • Slide 38
  • Slide 39
  • Slide 40
  • Slide 41
  • Slide 42
  • Slide 43
  • Slide 44
  • Slide 45
  • Slide 46
  • Slide 47
  • Slide 48
  • Slide 49
  • Slide 50
  • Slide 51
  • Slide 52
  • Slide 53
  • Slide 54
  • Slide 55
  • Slide 56
  • Slide 57
  • Slide 58
  • Slide 59
  • Slide 60
  • Slide 61
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  • Slide 63
  • Slide 64
  • Slide 65
  • Slide 66
  • Slide 67
  • Slide 68
  • Slide 69
  • Slide 70
  • Slide 71
  • Slide 72
  • Slide 73
  • Slide 74
  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

30

Home Network Categories

Computers (desktop PC PDA shared peripherals) Entertainment (TV DVD VCR camera stereo MP3) Telecomm (telephone cell phone intercom fax) Appliances (microwave fridge clock furnace airco

light) Telemetry (utility meter smokeburglar alarm babycam)

31

Fundamentally different properties

1 Devices have to be easy to install

2 The network and devices have to be foolproof in

operation

3 Low price is essential

4 The network needs sufficient capacity ( for multimedia

application)

5 The network interface and wiring have to be stable for

many years

6 Security and reliability will be very important

(minimize false alarm or misalarm) Home networks may be wired or wireless

32

Internetworks

bull Internetworks connect networks with different hardware

and softwarebull A collection of interconnected networks is called

an internetwork or internetbull Internet is one specific internetbull Gateways are used to make the connection and to

provide the necessary translation (protocol convertion)

33

Network Software

bull Protocol Hierarchies (Layer structure)bull Design Issues for the Layersbull Connection-Oriented and Connectionless Servicesbull Service Primitivesbull The Relationship of Services to Protocols

34

Network Software

Protocol Hierarchiesndash a series of layers (levels)

ndash lower layer provides service to higher layers

ndash protocol bull an agreement between the communication parties on how

communication is to proceed

ndash Peers bull the corresponding layers on different machines

ndash Network architecture a set of layers and protocols

ndash Protocol stack bull a list of protocols used by a certain system one protocol per

layer

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
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  • Slide 81
  • Slide 82

31

Fundamentally different properties

1 Devices have to be easy to install

2 The network and devices have to be foolproof in

operation

3 Low price is essential

4 The network needs sufficient capacity ( for multimedia

application)

5 The network interface and wiring have to be stable for

many years

6 Security and reliability will be very important

(minimize false alarm or misalarm) Home networks may be wired or wireless

32

Internetworks

bull Internetworks connect networks with different hardware

and softwarebull A collection of interconnected networks is called

an internetwork or internetbull Internet is one specific internetbull Gateways are used to make the connection and to

provide the necessary translation (protocol convertion)

33

Network Software

bull Protocol Hierarchies (Layer structure)bull Design Issues for the Layersbull Connection-Oriented and Connectionless Servicesbull Service Primitivesbull The Relationship of Services to Protocols

34

Network Software

Protocol Hierarchiesndash a series of layers (levels)

ndash lower layer provides service to higher layers

ndash protocol bull an agreement between the communication parties on how

communication is to proceed

ndash Peers bull the corresponding layers on different machines

ndash Network architecture a set of layers and protocols

ndash Protocol stack bull a list of protocols used by a certain system one protocol per

layer

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
  • Slide 11
  • Slide 12
  • Slide 13
  • Slide 14
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  • Slide 17
  • Slide 18
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  • Slide 20
  • Slide 21
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  • Slide 25
  • Slide 26
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  • Slide 28
  • Slide 29
  • Slide 30
  • Slide 31
  • Slide 32
  • Slide 33
  • Slide 34
  • Slide 35
  • Slide 36
  • Slide 37
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  • Slide 41
  • Slide 42
  • Slide 43
  • Slide 44
  • Slide 45
  • Slide 46
  • Slide 47
  • Slide 48
  • Slide 49
  • Slide 50
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  • Slide 64
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  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

32

Internetworks

bull Internetworks connect networks with different hardware

and softwarebull A collection of interconnected networks is called

an internetwork or internetbull Internet is one specific internetbull Gateways are used to make the connection and to

provide the necessary translation (protocol convertion)

33

Network Software

bull Protocol Hierarchies (Layer structure)bull Design Issues for the Layersbull Connection-Oriented and Connectionless Servicesbull Service Primitivesbull The Relationship of Services to Protocols

34

Network Software

Protocol Hierarchiesndash a series of layers (levels)

ndash lower layer provides service to higher layers

ndash protocol bull an agreement between the communication parties on how

communication is to proceed

ndash Peers bull the corresponding layers on different machines

ndash Network architecture a set of layers and protocols

ndash Protocol stack bull a list of protocols used by a certain system one protocol per

layer

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
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  • Slide 7
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  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

33

Network Software

bull Protocol Hierarchies (Layer structure)bull Design Issues for the Layersbull Connection-Oriented and Connectionless Servicesbull Service Primitivesbull The Relationship of Services to Protocols

34

Network Software

Protocol Hierarchiesndash a series of layers (levels)

ndash lower layer provides service to higher layers

ndash protocol bull an agreement between the communication parties on how

communication is to proceed

ndash Peers bull the corresponding layers on different machines

ndash Network architecture a set of layers and protocols

ndash Protocol stack bull a list of protocols used by a certain system one protocol per

layer

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
  • Slide 11
  • Slide 12
  • Slide 13
  • Slide 14
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  • Slide 35
  • Slide 36
  • Slide 37
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  • Slide 48
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  • Slide 64
  • Slide 65
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  • Slide 67
  • Slide 68
  • Slide 69
  • Slide 70
  • Slide 71
  • Slide 72
  • Slide 73
  • Slide 74
  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

34

Network Software

Protocol Hierarchiesndash a series of layers (levels)

ndash lower layer provides service to higher layers

ndash protocol bull an agreement between the communication parties on how

communication is to proceed

ndash Peers bull the corresponding layers on different machines

ndash Network architecture a set of layers and protocols

ndash Protocol stack bull a list of protocols used by a certain system one protocol per

layer

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
  • Slide 11
  • Slide 12
  • Slide 13
  • Slide 14
  • Slide 15
  • Slide 16
  • Slide 17
  • Slide 18
  • Slide 19
  • Slide 20
  • Slide 21
  • Slide 22
  • Slide 23
  • Slide 24
  • Slide 25
  • Slide 26
  • Slide 27
  • Slide 28
  • Slide 29
  • Slide 30
  • Slide 31
  • Slide 32
  • Slide 33
  • Slide 34
  • Slide 35
  • Slide 36
  • Slide 37
  • Slide 38
  • Slide 39
  • Slide 40
  • Slide 41
  • Slide 42
  • Slide 43
  • Slide 44
  • Slide 45
  • Slide 46
  • Slide 47
  • Slide 48
  • Slide 49
  • Slide 50
  • Slide 51
  • Slide 52
  • Slide 53
  • Slide 54
  • Slide 55
  • Slide 56
  • Slide 57
  • Slide 58
  • Slide 59
  • Slide 60
  • Slide 61
  • Slide 62
  • Slide 63
  • Slide 64
  • Slide 65
  • Slide 66
  • Slide 67
  • Slide 68
  • Slide 69
  • Slide 70
  • Slide 71
  • Slide 72
  • Slide 73
  • Slide 74
  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

35

Network SoftwareProtocol Hierarchies

Layers protocols and interfaces

Peer

Network Architecture A set of layers and protocols Protocol Stack A list of protocols used by a certain system one protocol per layer

Virtual Communication

PhysicalCommunication

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
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  • Slide 65
  • Slide 66
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  • Slide 69
  • Slide 70
  • Slide 71
  • Slide 72
  • Slide 73
  • Slide 74
  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

36

Layering

To make things simple modularization

Different layer has different functions

Create layer boundary such that description of services can be small number of interactions across boundary are minimized potential for interface standardized

Different level of abstraction in the handling of data (eg syntax semantics)

Provide appropriate services to upper layer

Use service primitives of lower layer

Network Software

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
  • Slide 11
  • Slide 12
  • Slide 13
  • Slide 14
  • Slide 15
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  • Slide 17
  • Slide 18
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  • Slide 21
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  • Slide 29
  • Slide 30
  • Slide 31
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  • Slide 33
  • Slide 34
  • Slide 35
  • Slide 36
  • Slide 37
  • Slide 38
  • Slide 39
  • Slide 40
  • Slide 41
  • Slide 42
  • Slide 43
  • Slide 44
  • Slide 45
  • Slide 46
  • Slide 47
  • Slide 48
  • Slide 49
  • Slide 50
  • Slide 51
  • Slide 52
  • Slide 53
  • Slide 54
  • Slide 55
  • Slide 56
  • Slide 57
  • Slide 58
  • Slide 59
  • Slide 60
  • Slide 61
  • Slide 62
  • Slide 63
  • Slide 64
  • Slide 65
  • Slide 66
  • Slide 67
  • Slide 68
  • Slide 69
  • Slide 70
  • Slide 71
  • Slide 72
  • Slide 73
  • Slide 74
  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

37

Protocol Hierarchies (2)

The philosopher-translator-secretary architecture

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
  • Slide 11
  • Slide 12
  • Slide 13
  • Slide 14
  • Slide 15
  • Slide 16
  • Slide 17
  • Slide 18
  • Slide 19
  • Slide 20
  • Slide 21
  • Slide 22
  • Slide 23
  • Slide 24
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  • Slide 26
  • Slide 27
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  • Slide 29
  • Slide 30
  • Slide 31
  • Slide 32
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  • Slide 34
  • Slide 35
  • Slide 36
  • Slide 37
  • Slide 38
  • Slide 39
  • Slide 40
  • Slide 41
  • Slide 42
  • Slide 43
  • Slide 44
  • Slide 45
  • Slide 46
  • Slide 47
  • Slide 48
  • Slide 49
  • Slide 50
  • Slide 51
  • Slide 52
  • Slide 53
  • Slide 54
  • Slide 55
  • Slide 56
  • Slide 57
  • Slide 58
  • Slide 59
  • Slide 60
  • Slide 61
  • Slide 62
  • Slide 63
  • Slide 64
  • Slide 65
  • Slide 66
  • Slide 67
  • Slide 68
  • Slide 69
  • Slide 70
  • Slide 71
  • Slide 72
  • Slide 73
  • Slide 74
  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

38

Protocol Hierarchies (3)

Example information flow supporting virtual communication in layer 5

Message segmentation Encapsulation

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
  • Slide 11
  • Slide 12
  • Slide 13
  • Slide 14
  • Slide 15
  • Slide 16
  • Slide 17
  • Slide 18
  • Slide 19
  • Slide 20
  • Slide 21
  • Slide 22
  • Slide 23
  • Slide 24
  • Slide 25
  • Slide 26
  • Slide 27
  • Slide 28
  • Slide 29
  • Slide 30
  • Slide 31
  • Slide 32
  • Slide 33
  • Slide 34
  • Slide 35
  • Slide 36
  • Slide 37
  • Slide 38
  • Slide 39
  • Slide 40
  • Slide 41
  • Slide 42
  • Slide 43
  • Slide 44
  • Slide 45
  • Slide 46
  • Slide 47
  • Slide 48
  • Slide 49
  • Slide 50
  • Slide 51
  • Slide 52
  • Slide 53
  • Slide 54
  • Slide 55
  • Slide 56
  • Slide 57
  • Slide 58
  • Slide 59
  • Slide 60
  • Slide 61
  • Slide 62
  • Slide 63
  • Slide 64
  • Slide 65
  • Slide 66
  • Slide 67
  • Slide 68
  • Slide 69
  • Slide 70
  • Slide 71
  • Slide 72
  • Slide 73
  • Slide 74
  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

39

Design Issues for the Layers

bull Addressing (telephone number e-mail address IP addresshellip)

bull Error Control (error correction codes ARQ HARQhellip)bull Flow Control (feedback-based rate-based)bull Multiplexing (gathering several small messages with the

same destination into a single large message or vice versa Demultiplexing)

bull Routing (directing traffic to the destination)

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
  • Slide 11
  • Slide 12
  • Slide 13
  • Slide 14
  • Slide 15
  • Slide 16
  • Slide 17
  • Slide 18
  • Slide 19
  • Slide 20
  • Slide 21
  • Slide 22
  • Slide 23
  • Slide 24
  • Slide 25
  • Slide 26
  • Slide 27
  • Slide 28
  • Slide 29
  • Slide 30
  • Slide 31
  • Slide 32
  • Slide 33
  • Slide 34
  • Slide 35
  • Slide 36
  • Slide 37
  • Slide 38
  • Slide 39
  • Slide 40
  • Slide 41
  • Slide 42
  • Slide 43
  • Slide 44
  • Slide 45
  • Slide 46
  • Slide 47
  • Slide 48
  • Slide 49
  • Slide 50
  • Slide 51
  • Slide 52
  • Slide 53
  • Slide 54
  • Slide 55
  • Slide 56
  • Slide 57
  • Slide 58
  • Slide 59
  • Slide 60
  • Slide 61
  • Slide 62
  • Slide 63
  • Slide 64
  • Slide 65
  • Slide 66
  • Slide 67
  • Slide 68
  • Slide 69
  • Slide 70
  • Slide 71
  • Slide 72
  • Slide 73
  • Slide 74
  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

40

Design Issues for Layers

Identify senders and receivers ndash multiple computers and processes addressing

Data transferndash simplex half-duplex full-duplex communication

ndash of logical channels per connections priorities Error control

ndash error detection

ndash error correction Sequencing of pieces

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
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  • Slide 54
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  • Slide 65
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  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

41

Design Issues for Layers Flow control

ndash feedback from the receiver

ndash agreed upon transmission rate Length of messages

ndash long messages disassemble transmit and reassmeble messages

ndash short messages gather several small messages Multiplexing and Demultiplexing

ndash when expensive to set up a separate connection

ndash needed in physical layer Routing split over two or more layers

ndash High level London -gt France or Germany -gt Rome

ndash Low level many available circuits

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
  • Slide 11
  • Slide 12
  • Slide 13
  • Slide 14
  • Slide 15
  • Slide 16
  • Slide 17
  • Slide 18
  • Slide 19
  • Slide 20
  • Slide 21
  • Slide 22
  • Slide 23
  • Slide 24
  • Slide 25
  • Slide 26
  • Slide 27
  • Slide 28
  • Slide 29
  • Slide 30
  • Slide 31
  • Slide 32
  • Slide 33
  • Slide 34
  • Slide 35
  • Slide 36
  • Slide 37
  • Slide 38
  • Slide 39
  • Slide 40
  • Slide 41
  • Slide 42
  • Slide 43
  • Slide 44
  • Slide 45
  • Slide 46
  • Slide 47
  • Slide 48
  • Slide 49
  • Slide 50
  • Slide 51
  • Slide 52
  • Slide 53
  • Slide 54
  • Slide 55
  • Slide 56
  • Slide 57
  • Slide 58
  • Slide 59
  • Slide 60
  • Slide 61
  • Slide 62
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  • Slide 64
  • Slide 65
  • Slide 66
  • Slide 67
  • Slide 68
  • Slide 69
  • Slide 70
  • Slide 71
  • Slide 72
  • Slide 73
  • Slide 74
  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

42

Connection-Oriented and Connectionless Services

Six different types of service

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
  • Slide 11
  • Slide 12
  • Slide 13
  • Slide 14
  • Slide 15
  • Slide 16
  • Slide 17
  • Slide 18
  • Slide 19
  • Slide 20
  • Slide 21
  • Slide 22
  • Slide 23
  • Slide 24
  • Slide 25
  • Slide 26
  • Slide 27
  • Slide 28
  • Slide 29
  • Slide 30
  • Slide 31
  • Slide 32
  • Slide 33
  • Slide 34
  • Slide 35
  • Slide 36
  • Slide 37
  • Slide 38
  • Slide 39
  • Slide 40
  • Slide 41
  • Slide 42
  • Slide 43
  • Slide 44
  • Slide 45
  • Slide 46
  • Slide 47
  • Slide 48
  • Slide 49
  • Slide 50
  • Slide 51
  • Slide 52
  • Slide 53
  • Slide 54
  • Slide 55
  • Slide 56
  • Slide 57
  • Slide 58
  • Slide 59
  • Slide 60
  • Slide 61
  • Slide 62
  • Slide 63
  • Slide 64
  • Slide 65
  • Slide 66
  • Slide 67
  • Slide 68
  • Slide 69
  • Slide 70
  • Slide 71
  • Slide 72
  • Slide 73
  • Slide 74
  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

43

Service Primitives (Operations)

Five service primitives for implementing a simple connection-oriented service

A service is formally defined by a set of primitives (operations) available to a user process to access the services

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
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  • Slide 14
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  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

44

Service Primitives (2)

Packets sent in a simple client-server interaction on a connection-oriented network

If the protocol stack is located in the operating system

the primitives are normally system calls

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
  • Slide 11
  • Slide 12
  • Slide 13
  • Slide 14
  • Slide 15
  • Slide 16
  • Slide 17
  • Slide 18
  • Slide 19
  • Slide 20
  • Slide 21
  • Slide 22
  • Slide 23
  • Slide 24
  • Slide 25
  • Slide 26
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  • Slide 28
  • Slide 29
  • Slide 30
  • Slide 31
  • Slide 32
  • Slide 33
  • Slide 34
  • Slide 35
  • Slide 36
  • Slide 37
  • Slide 38
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  • Slide 41
  • Slide 42
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  • Slide 45
  • Slide 46
  • Slide 47
  • Slide 48
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  • Slide 66
  • Slide 67
  • Slide 68
  • Slide 69
  • Slide 70
  • Slide 71
  • Slide 72
  • Slide 73
  • Slide 74
  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

45

Services to Protocols Relationship

The relationship between a service and a protocol

middotThe service defines what operations the layer is prepared to perform on behalf of its users

middotA service is a set of primitives that a layer provides to the layer above it

middotA protocol is a set of rules governing the format and meaning of the packets which areexchanged by the peer entities in the same layer

Service Providers

Service Users

Services related to the interfaces between layers Protocols related to the packets sent between peer entities on different machine

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
  • Slide 11
  • Slide 12
  • Slide 13
  • Slide 14
  • Slide 15
  • Slide 16
  • Slide 17
  • Slide 18
  • Slide 19
  • Slide 20
  • Slide 21
  • Slide 22
  • Slide 23
  • Slide 24
  • Slide 25
  • Slide 26
  • Slide 27
  • Slide 28
  • Slide 29
  • Slide 30
  • Slide 31
  • Slide 32
  • Slide 33
  • Slide 34
  • Slide 35
  • Slide 36
  • Slide 37
  • Slide 38
  • Slide 39
  • Slide 40
  • Slide 41
  • Slide 42
  • Slide 43
  • Slide 44
  • Slide 45
  • Slide 46
  • Slide 47
  • Slide 48
  • Slide 49
  • Slide 50
  • Slide 51
  • Slide 52
  • Slide 53
  • Slide 54
  • Slide 55
  • Slide 56
  • Slide 57
  • Slide 58
  • Slide 59
  • Slide 60
  • Slide 61
  • Slide 62
  • Slide 63
  • Slide 64
  • Slide 65
  • Slide 66
  • Slide 67
  • Slide 68
  • Slide 69
  • Slide 70
  • Slide 71
  • Slide 72
  • Slide 73
  • Slide 74
  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

46

Reference Models

bull The OSI Reference Model

bull The TCPIP Reference Model

bull A Comparison of OSI and TCPIP

bull A Critique of the OSI Model and Protocols

bull A Critique of the TCPIP Reference Model

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
  • Slide 11
  • Slide 12
  • Slide 13
  • Slide 14
  • Slide 15
  • Slide 16
  • Slide 17
  • Slide 18
  • Slide 19
  • Slide 20
  • Slide 21
  • Slide 22
  • Slide 23
  • Slide 24
  • Slide 25
  • Slide 26
  • Slide 27
  • Slide 28
  • Slide 29
  • Slide 30
  • Slide 31
  • Slide 32
  • Slide 33
  • Slide 34
  • Slide 35
  • Slide 36
  • Slide 37
  • Slide 38
  • Slide 39
  • Slide 40
  • Slide 41
  • Slide 42
  • Slide 43
  • Slide 44
  • Slide 45
  • Slide 46
  • Slide 47
  • Slide 48
  • Slide 49
  • Slide 50
  • Slide 51
  • Slide 52
  • Slide 53
  • Slide 54
  • Slide 55
  • Slide 56
  • Slide 57
  • Slide 58
  • Slide 59
  • Slide 60
  • Slide 61
  • Slide 62
  • Slide 63
  • Slide 64
  • Slide 65
  • Slide 66
  • Slide 67
  • Slide 68
  • Slide 69
  • Slide 70
  • Slide 71
  • Slide 72
  • Slide 73
  • Slide 74
  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

47

The design principle of the OSI reference model

bull A layer should be created where a different abstraction is needed

bull Each layer should perform a well defined functionbull The function of each layer can be chosen as an

international standardbull The layer boundaries should be chosen to

minimize the information flow across the interfaces

bull The number of layers should be not too large or not too small

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
  • Slide 11
  • Slide 12
  • Slide 13
  • Slide 14
  • Slide 15
  • Slide 16
  • Slide 17
  • Slide 18
  • Slide 19
  • Slide 20
  • Slide 21
  • Slide 22
  • Slide 23
  • Slide 24
  • Slide 25
  • Slide 26
  • Slide 27
  • Slide 28
  • Slide 29
  • Slide 30
  • Slide 31
  • Slide 32
  • Slide 33
  • Slide 34
  • Slide 35
  • Slide 36
  • Slide 37
  • Slide 38
  • Slide 39
  • Slide 40
  • Slide 41
  • Slide 42
  • Slide 43
  • Slide 44
  • Slide 45
  • Slide 46
  • Slide 47
  • Slide 48
  • Slide 49
  • Slide 50
  • Slide 51
  • Slide 52
  • Slide 53
  • Slide 54
  • Slide 55
  • Slide 56
  • Slide 57
  • Slide 58
  • Slide 59
  • Slide 60
  • Slide 61
  • Slide 62
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  • Slide 64
  • Slide 65
  • Slide 66
  • Slide 67
  • Slide 68
  • Slide 69
  • Slide 70
  • Slide 71
  • Slide 72
  • Slide 73
  • Slide 74
  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

48

Reference Models

The OSI reference model

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
  • Slide 11
  • Slide 12
  • Slide 13
  • Slide 14
  • Slide 15
  • Slide 16
  • Slide 17
  • Slide 18
  • Slide 19
  • Slide 20
  • Slide 21
  • Slide 22
  • Slide 23
  • Slide 24
  • Slide 25
  • Slide 26
  • Slide 27
  • Slide 28
  • Slide 29
  • Slide 30
  • Slide 31
  • Slide 32
  • Slide 33
  • Slide 34
  • Slide 35
  • Slide 36
  • Slide 37
  • Slide 38
  • Slide 39
  • Slide 40
  • Slide 41
  • Slide 42
  • Slide 43
  • Slide 44
  • Slide 45
  • Slide 46
  • Slide 47
  • Slide 48
  • Slide 49
  • Slide 50
  • Slide 51
  • Slide 52
  • Slide 53
  • Slide 54
  • Slide 55
  • Slide 56
  • Slide 57
  • Slide 58
  • Slide 59
  • Slide 60
  • Slide 61
  • Slide 62
  • Slide 63
  • Slide 64
  • Slide 65
  • Slide 66
  • Slide 67
  • Slide 68
  • Slide 69
  • Slide 70
  • Slide 71
  • Slide 72
  • Slide 73
  • Slide 74
  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

49

The functions of the seven layersbull The physical layer is concerned with transmitting raw bits over a

communication channelbull The data link layer performs flow control and also transforms a

raw transmission facility into a line that appears error free (ARQ)bull The network layer controls the operation of the subnet eg

routing flow control internetworkinghellipbull The transport layer performs assembling and disassembling

isolates the upper layers from the changes in the network hardware and determines the type of services

bull The session layer establishes sessions (dialog control hellip)bull The presentation layer is concerned with the syntax and semanticsbull The application layer contains a variety of commonly used

protocols (eg Hyper Text Transfer Protocol for WWW file transfer e-mail network newshellip)

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
  • Slide 11
  • Slide 12
  • Slide 13
  • Slide 14
  • Slide 15
  • Slide 16
  • Slide 17
  • Slide 18
  • Slide 19
  • Slide 20
  • Slide 21
  • Slide 22
  • Slide 23
  • Slide 24
  • Slide 25
  • Slide 26
  • Slide 27
  • Slide 28
  • Slide 29
  • Slide 30
  • Slide 31
  • Slide 32
  • Slide 33
  • Slide 34
  • Slide 35
  • Slide 36
  • Slide 37
  • Slide 38
  • Slide 39
  • Slide 40
  • Slide 41
  • Slide 42
  • Slide 43
  • Slide 44
  • Slide 45
  • Slide 46
  • Slide 47
  • Slide 48
  • Slide 49
  • Slide 50
  • Slide 51
  • Slide 52
  • Slide 53
  • Slide 54
  • Slide 55
  • Slide 56
  • Slide 57
  • Slide 58
  • Slide 59
  • Slide 60
  • Slide 61
  • Slide 62
  • Slide 63
  • Slide 64
  • Slide 65
  • Slide 66
  • Slide 67
  • Slide 68
  • Slide 69
  • Slide 70
  • Slide 71
  • Slide 72
  • Slide 73
  • Slide 74
  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

50

Reference Models (2)

The TCPIP reference model

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
  • Slide 11
  • Slide 12
  • Slide 13
  • Slide 14
  • Slide 15
  • Slide 16
  • Slide 17
  • Slide 18
  • Slide 19
  • Slide 20
  • Slide 21
  • Slide 22
  • Slide 23
  • Slide 24
  • Slide 25
  • Slide 26
  • Slide 27
  • Slide 28
  • Slide 29
  • Slide 30
  • Slide 31
  • Slide 32
  • Slide 33
  • Slide 34
  • Slide 35
  • Slide 36
  • Slide 37
  • Slide 38
  • Slide 39
  • Slide 40
  • Slide 41
  • Slide 42
  • Slide 43
  • Slide 44
  • Slide 45
  • Slide 46
  • Slide 47
  • Slide 48
  • Slide 49
  • Slide 50
  • Slide 51
  • Slide 52
  • Slide 53
  • Slide 54
  • Slide 55
  • Slide 56
  • Slide 57
  • Slide 58
  • Slide 59
  • Slide 60
  • Slide 61
  • Slide 62
  • Slide 63
  • Slide 64
  • Slide 65
  • Slide 66
  • Slide 67
  • Slide 68
  • Slide 69
  • Slide 70
  • Slide 71
  • Slide 72
  • Slide 73
  • Slide 74
  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

51

Reference Models (3)

Protocols and networks in the TCPIP model initially

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
  • Slide 11
  • Slide 12
  • Slide 13
  • Slide 14
  • Slide 15
  • Slide 16
  • Slide 17
  • Slide 18
  • Slide 19
  • Slide 20
  • Slide 21
  • Slide 22
  • Slide 23
  • Slide 24
  • Slide 25
  • Slide 26
  • Slide 27
  • Slide 28
  • Slide 29
  • Slide 30
  • Slide 31
  • Slide 32
  • Slide 33
  • Slide 34
  • Slide 35
  • Slide 36
  • Slide 37
  • Slide 38
  • Slide 39
  • Slide 40
  • Slide 41
  • Slide 42
  • Slide 43
  • Slide 44
  • Slide 45
  • Slide 46
  • Slide 47
  • Slide 48
  • Slide 49
  • Slide 50
  • Slide 51
  • Slide 52
  • Slide 53
  • Slide 54
  • Slide 55
  • Slide 56
  • Slide 57
  • Slide 58
  • Slide 59
  • Slide 60
  • Slide 61
  • Slide 62
  • Slide 63
  • Slide 64
  • Slide 65
  • Slide 66
  • Slide 67
  • Slide 68
  • Slide 69
  • Slide 70
  • Slide 71
  • Slide 72
  • Slide 73
  • Slide 74
  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

52

Comparing OSI and TCPIP Models

Concepts central to the OSI modelbull Services defines layerrsquos semantics

bull Interfaces tells the processes above it how to access it

bull ProtocolsProbably the biggest contribution of the OSI model is to make the

distinction between these three concepts explicit

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
  • Slide 11
  • Slide 12
  • Slide 13
  • Slide 14
  • Slide 15
  • Slide 16
  • Slide 17
  • Slide 18
  • Slide 19
  • Slide 20
  • Slide 21
  • Slide 22
  • Slide 23
  • Slide 24
  • Slide 25
  • Slide 26
  • Slide 27
  • Slide 28
  • Slide 29
  • Slide 30
  • Slide 31
  • Slide 32
  • Slide 33
  • Slide 34
  • Slide 35
  • Slide 36
  • Slide 37
  • Slide 38
  • Slide 39
  • Slide 40
  • Slide 41
  • Slide 42
  • Slide 43
  • Slide 44
  • Slide 45
  • Slide 46
  • Slide 47
  • Slide 48
  • Slide 49
  • Slide 50
  • Slide 51
  • Slide 52
  • Slide 53
  • Slide 54
  • Slide 55
  • Slide 56
  • Slide 57
  • Slide 58
  • Slide 59
  • Slide 60
  • Slide 61
  • Slide 62
  • Slide 63
  • Slide 64
  • Slide 65
  • Slide 66
  • Slide 67
  • Slide 68
  • Slide 69
  • Slide 70
  • Slide 71
  • Slide 72
  • Slide 73
  • Slide 74
  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

53

A Critique of the OSI Model and Protocols

Why OSI did not take over the world

bull Bad timing

bull Bad technology

bull Bad implementations

bull Bad politics

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
  • Slide 11
  • Slide 12
  • Slide 13
  • Slide 14
  • Slide 15
  • Slide 16
  • Slide 17
  • Slide 18
  • Slide 19
  • Slide 20
  • Slide 21
  • Slide 22
  • Slide 23
  • Slide 24
  • Slide 25
  • Slide 26
  • Slide 27
  • Slide 28
  • Slide 29
  • Slide 30
  • Slide 31
  • Slide 32
  • Slide 33
  • Slide 34
  • Slide 35
  • Slide 36
  • Slide 37
  • Slide 38
  • Slide 39
  • Slide 40
  • Slide 41
  • Slide 42
  • Slide 43
  • Slide 44
  • Slide 45
  • Slide 46
  • Slide 47
  • Slide 48
  • Slide 49
  • Slide 50
  • Slide 51
  • Slide 52
  • Slide 53
  • Slide 54
  • Slide 55
  • Slide 56
  • Slide 57
  • Slide 58
  • Slide 59
  • Slide 60
  • Slide 61
  • Slide 62
  • Slide 63
  • Slide 64
  • Slide 65
  • Slide 66
  • Slide 67
  • Slide 68
  • Slide 69
  • Slide 70
  • Slide 71
  • Slide 72
  • Slide 73
  • Slide 74
  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

54

Bad Timing

The apocalypse of the two elephants

new discovery

investment opportunity

right time to make

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
  • Slide 11
  • Slide 12
  • Slide 13
  • Slide 14
  • Slide 15
  • Slide 16
  • Slide 17
  • Slide 18
  • Slide 19
  • Slide 20
  • Slide 21
  • Slide 22
  • Slide 23
  • Slide 24
  • Slide 25
  • Slide 26
  • Slide 27
  • Slide 28
  • Slide 29
  • Slide 30
  • Slide 31
  • Slide 32
  • Slide 33
  • Slide 34
  • Slide 35
  • Slide 36
  • Slide 37
  • Slide 38
  • Slide 39
  • Slide 40
  • Slide 41
  • Slide 42
  • Slide 43
  • Slide 44
  • Slide 45
  • Slide 46
  • Slide 47
  • Slide 48
  • Slide 49
  • Slide 50
  • Slide 51
  • Slide 52
  • Slide 53
  • Slide 54
  • Slide 55
  • Slide 56
  • Slide 57
  • Slide 58
  • Slide 59
  • Slide 60
  • Slide 61
  • Slide 62
  • Slide 63
  • Slide 64
  • Slide 65
  • Slide 66
  • Slide 67
  • Slide 68
  • Slide 69
  • Slide 70
  • Slide 71
  • Slide 72
  • Slide 73
  • Slide 74
  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

55

Bad Technology

bull The choice of seven layers was political

- session and presentation layers are nearly empty

- Data and network layers are overfull

bull The OSI model is extraordinarily complex

bull Some functions eg addressing flow control error control reappear again and again

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
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  • Slide 37
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  • Slide 43
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  • Slide 47
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  • Slide 49
  • Slide 50
  • Slide 51
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  • Slide 53
  • Slide 54
  • Slide 55
  • Slide 56
  • Slide 57
  • Slide 58
  • Slide 59
  • Slide 60
  • Slide 61
  • Slide 62
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  • Slide 64
  • Slide 65
  • Slide 66
  • Slide 67
  • Slide 68
  • Slide 69
  • Slide 70
  • Slide 71
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  • Slide 73
  • Slide 74
  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

56

Bad Implementations

bull Huge Unwieldy and Slow

Bad Politicsbull Bureaucrats involved too much (European

telecommunication ministries community us government)

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
  • Slide 11
  • Slide 12
  • Slide 13
  • Slide 14
  • Slide 15
  • Slide 16
  • Slide 17
  • Slide 18
  • Slide 19
  • Slide 20
  • Slide 21
  • Slide 22
  • Slide 23
  • Slide 24
  • Slide 25
  • Slide 26
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  • Slide 28
  • Slide 29
  • Slide 30
  • Slide 31
  • Slide 32
  • Slide 33
  • Slide 34
  • Slide 35
  • Slide 36
  • Slide 37
  • Slide 38
  • Slide 39
  • Slide 40
  • Slide 41
  • Slide 42
  • Slide 43
  • Slide 44
  • Slide 45
  • Slide 46
  • Slide 47
  • Slide 48
  • Slide 49
  • Slide 50
  • Slide 51
  • Slide 52
  • Slide 53
  • Slide 54
  • Slide 55
  • Slide 56
  • Slide 57
  • Slide 58
  • Slide 59
  • Slide 60
  • Slide 61
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  • Slide 63
  • Slide 64
  • Slide 65
  • Slide 66
  • Slide 67
  • Slide 68
  • Slide 69
  • Slide 70
  • Slide 71
  • Slide 72
  • Slide 73
  • Slide 74
  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

57

A Critique of the TCPIP Reference Model

Problemsbull Service interface and protocol not distinguishedbull Not a general modelbull Host-to-network ldquolayerrdquo not really a layer (is an interface)bull No mention of physical and data link layersbull Minor protocols deeply entrenched hard to replace

(The virtual terminal protocol TELNET was designed for mechanical teletype terminal)

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
  • Slide 11
  • Slide 12
  • Slide 13
  • Slide 14
  • Slide 15
  • Slide 16
  • Slide 17
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  • Slide 21
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  • Slide 31
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  • Slide 34
  • Slide 35
  • Slide 36
  • Slide 37
  • Slide 38
  • Slide 39
  • Slide 40
  • Slide 41
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  • Slide 45
  • Slide 46
  • Slide 47
  • Slide 48
  • Slide 49
  • Slide 50
  • Slide 51
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  • Slide 56
  • Slide 57
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  • Slide 67
  • Slide 68
  • Slide 69
  • Slide 70
  • Slide 71
  • Slide 72
  • Slide 73
  • Slide 74
  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

58

Hybrid Model

The hybrid reference model to be used in this book

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
  • Slide 11
  • Slide 12
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  • Slide 21
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  • Slide 33
  • Slide 34
  • Slide 35
  • Slide 36
  • Slide 37
  • Slide 38
  • Slide 39
  • Slide 40
  • Slide 41
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  • Slide 43
  • Slide 44
  • Slide 45
  • Slide 46
  • Slide 47
  • Slide 48
  • Slide 49
  • Slide 50
  • Slide 51
  • Slide 52
  • Slide 53
  • Slide 54
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  • Slide 56
  • Slide 57
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  • Slide 60
  • Slide 61
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  • Slide 65
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  • Slide 69
  • Slide 70
  • Slide 71
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  • Slide 73
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  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

59

Example Networks

bull The Internet

bull Connection-Oriented Networks X25 Frame Relay and ATM

bull Ethernet

bull Wireless LANs 80211

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
  • Slide 11
  • Slide 12
  • Slide 13
  • Slide 14
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  • Slide 36
  • Slide 37
  • Slide 38
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  • Slide 40
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  • Slide 46
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  • Slide 50
  • Slide 51
  • Slide 52
  • Slide 53
  • Slide 54
  • Slide 55
  • Slide 56
  • Slide 57
  • Slide 58
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  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

60

The ARPANET

(a) Structure of the telephone system(b) Baranrsquos proposed distributed switching system

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
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  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

61

1048576

Original backbone of Internet

Wide area network around which TCPIP was developed Funding from Advanced Research Project Agency1048576 Initial speed 50 Kbps

ARPANET (1969-1989)

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
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  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

62

The ARPANET (2)

The original ARPANET design

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
  • Slide 11
  • Slide 12
  • Slide 13
  • Slide 14
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  • Slide 49
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  • Slide 56
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  • Slide 61
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  • Slide 65
  • Slide 66
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  • Slide 68
  • Slide 69
  • Slide 70
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  • Slide 73
  • Slide 74
  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

63

The ARPANET (3)

Growth of the ARPANET (a) December 1969 (b) July 1970(c) March 1971 (d) April 1972 (e) September 1972

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
  • Slide 11
  • Slide 12
  • Slide 13
  • Slide 14
  • Slide 15
  • Slide 16
  • Slide 17
  • Slide 18
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  • Slide 21
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  • Slide 33
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  • Slide 37
  • Slide 38
  • Slide 39
  • Slide 40
  • Slide 41
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  • Slide 65
  • Slide 66
  • Slide 67
  • Slide 68
  • Slide 69
  • Slide 70
  • Slide 71
  • Slide 72
  • Slide 73
  • Slide 74
  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

64

NSFNET

The NSFNET backbone in 1988

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
  • Slide 11
  • Slide 12
  • Slide 13
  • Slide 14
  • Slide 15
  • Slide 16
  • Slide 17
  • Slide 18
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  • Slide 20
  • Slide 21
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  • Slide 30
  • Slide 31
  • Slide 32
  • Slide 33
  • Slide 34
  • Slide 35
  • Slide 36
  • Slide 37
  • Slide 38
  • Slide 39
  • Slide 40
  • Slide 41
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  • Slide 45
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  • Slide 48
  • Slide 49
  • Slide 50
  • Slide 51
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  • Slide 65
  • Slide 66
  • Slide 67
  • Slide 68
  • Slide 69
  • Slide 70
  • Slide 71
  • Slide 72
  • Slide 73
  • Slide 74
  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

65

Funded by National Science Foundation1048576 Motivation Internet backbone to connect all scientists and engineers1048576 Introduced Internet hierarchy ndash Wide area backbone spanning geographic US ndash Many mid-level (regional) networks that attach to backbone ndash Campus networks at lowest level1048576 Initial speed 1544 Mbps

NSFNET (1987-1992)

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
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  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

66

Internet Usage

Traditional applications (1970 ndash 1990)

bull E-mail

bull News

bull Remote login

bull File transferWorld Wide Web changed all that and brought millions of new

nonacademic users

Internet Service Providers (ISP) offer individual users at home the ability to call up one of their machines and connect to the Internet to access all kinds of services

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
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  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

67

Architecture of the Internet

Overview of the Internet

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
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  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

68

ATM Virtual Circuits

A virtual circuit

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
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  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

69

ATM Virtual Circuits (2)

An ATM cell

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
  • Slide 11
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  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

70

The ATM Reference Model

The ATM reference model

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
  • Slide 11
  • Slide 12
  • Slide 13
  • Slide 14
  • Slide 15
  • Slide 16
  • Slide 17
  • Slide 18
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  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

71

The ATM Reference Model (2)

The ATM layers and sublayers and their functions

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
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  • Slide 72
  • Slide 73
  • Slide 74
  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

72

Ethernet

Architecture of the original Ethernet

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
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  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

73

Wireless LANs

(a) Wireless networking with a base station(b) Ad hoc networking

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
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  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

74

Wireless LANs (2)

The range of a single radio may not cover the entire system

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
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  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

75

Wireless LANs (3)

A multicell 80211 network

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
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  • Slide 74
  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

76

Network Standardization

bull Whorsquos Who in the Telecommunications Worldbull Whorsquos Who in the International Standards Worldbull Whorsquos Who in the Internet Standards World

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
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  • Slide 74
  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

77

Telecommunication International Telecommunication Union (ITU) Telecommunications Standardization Sector (ITU-T)

International Standard International Standards Organization (ISO) ANSI (USA) ETSI (Europe) BSI (Great Britain) AFNOR(France) IEEE

Internet Standard Internet Activities Board (IAB 1983) Internet Research Task Force (IRTF) Internet Engineering Task Force (IETF) Request for Comments (RFC) httpcache2cisnctuedutwDocumentsrfc ftpftpmeriteduinternetdocumentsrfc Internet Draft Standard Internet Standard

Standard Organizations

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
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  • Slide 74
  • Slide 75
  • Slide 76
  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

78

ITU

bull Main sectorsbull Radiocommunicationsbull Telecommunications Standardizationbull Development

bull Classes of Membersbull National governmentsbull Sector membersbull Associate membersbull Regulatory agencies

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
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  • Slide 77
  • Slide 78
  • Slide 79
  • Slide 80
  • Slide 81
  • Slide 82

79

IEEE 802 Standards

The 802 working groups The important ones are marked with The ones marked with are hibernating The one marked with dagger gave up

80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
  • Slide 6
  • Slide 7
  • Slide 8
  • Slide 9
  • Slide 10
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80

Metric Units

The principal metric prefixes

81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

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81

1969 ARPANET

1970rsquos ALOHA Ethernet DECNet SNA

1980rsquos Proliferation of LAN (Ethernet Token Ring)

1987 High speed LANMAN (FDDI) BISDN (ATM)

1990 High speed WAN (NSFNET 45 Mbps)

1993 High speed Ethernet (Fast Ethernet EtherSwitch)

1996 Interent II (622Mbps)

1998 Gigabit Ethernet

History of Networking

82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
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82

TANET 199112 64Kbps 199212 256Kbps 199410 512Kbps 199512 T1 19975 T3 Current Status T3 to USA by the end of 1998 (Policy routing enforced) T3 backbone around the island Add a T3 from MOE to CCU Internet II (19996)

HiNet (1994) SeedNet(數位聯合股份公司 )

History of Taiwanrsquos Network

  • Slide 1
  • Slide 2
  • Slide 3
  • Slide 4
  • Slide 5
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