int. ref : infraste.ppt page 1 t e l e c o m 東吳大學二代高速校園網路工程簡報資料...

東吳大學二代高速校園網路工程簡報資料Int. Ref : Infraste .PPT

T E L E C O M

SolutionSolution


T E L E C O M

Why ATM

Standard

Typical switch solution &

problem

Our solution

2

Solution- Agenda

東吳大學二代高速校園網路工程簡報資料 3Int. Ref : Infraste .PPT

T E L E C O M

Why ATM ?Why ATM ?


T E L E C O MAreas in which ATM might be applied

Server Backbone

Desktop LAN

Building Backbone

Campus Backbone

Wide Area Network


T E L E C O M

What are the alternatives to ATM?

Desktop LAN

Building backbone

Campus backbone

Server backbone

Wide Area Network

DrawbacksBenefitsAlternatives

New NICsNew SoftwareExpensive

QoSSwitched 10BaseTSwitched 100BaseTxSwitched token ring

ComplexQoSTraffic managementTopology

100BaseFxgigabit EthernetFDDI



New softwareQoS100BaseTxgigabit EthernetFDDI / CDDI

ExpensivePoor availability

QoSTraffic managementTopology

Frame RelayISDN


T E L E C O M

Conclusion:

Most likely ATM deployment is in the backbone

Desktop LAN

Building backbone

Campus backbone

Server backbone

Wide Area Network

DrawbacksBenefitsAlternatives

New NICsNew SoftwareExpensive

QoSSwitched 10BaseTSwitched 100BaseTxSwitched token ring





New softwareQoS100BaseTxgigabit EthernetFDDI / CDDI

ExpensivePoor availability


Frame RelayISDN

Complex


T E L E C O M

Conclusion:

Most likely ATM deployment is in the backbone

Server Backbone

Building Backbone

Campus Backbone


T E L E C O M

Ok, I understandthat ATM is best used for the

premise backbone. What other>> choices << do I have?


T E L E C O M

Future scalability - the FDDI fallacy

Traditional router / hub model

We invested in FDDI as a backbone technology and architecture for the future

FDDI looked like it would support voice and video and scale, i.e.., FDDI-II and FFOL (up to 2.4 Gbps)

To avoid the FDDI fallacy, invest in a technology that has a defined real-time support and scalable future


T E L E C O M

ATM versus Ethernet

Bandwidth options

ATMATM EthernetEthernet

Ban

dw

idth

Op

tio

ns

Comparisons are incorrectly made between gigabit Ethernet and ATM OC-12c / STM-4c

1.5M

2M

25.6M

34M

45M

155M

622M

2.4G

9.6G*

10M

100M

1000M*

ATM is available in a wide range of bandwidth levels


T E L E C O M

ATMATM

Des

kto

p O

pti

on

s

10M Ethernet

100M Ethernet

16M Token Ring

25.6M ATM

100M FDDI

100M CDDI

155M ATM

Ethernet *Ethernet *

10M Ethernet

100M Ethernet

ATM versus Ethernet Desktop options

The selection of backbone technology directly affects desktop alternatives

* Xylan is able to extend desktop support to Token Ring, FDDI and CDDI


T E L E C O M

ATM versus Ethernet Allocation of bandwidth: ATM

155M ATM

Backbone:155M ATM622M ATM

Server:155M ATM

Let’s say the RED users want to FTP and the BLUE users are watching a training video

What tools does ATM offer? Connections with guaranteed b

andwidth and QoS for different applications


T E L E C O M

ATM versus Ethernet Allocation of bandwidth: Ethernet

None. First come, first serve

100M Ethernet

Backbone:100M Ethernet

(1000M Ethernet)

Server:100M Ethernet

Let’s say the RED users want to FTP and the BLUE users are watching a training video

What tools does Ethernet offer?


T E L E C O M

Route discoverymechanism

Topologiessupported

Protocol layer re-route time

Physical layerre-route time

EthernetATM

Spanning TreePNNI

Loop-free treeAny (tree, ring, mesh)

10-30 seconds100-200 milliseconds

Not available10-20 milliseconds

ATM versus Ethernet Topological resilience

The Ethernet backbone Achilles’ heel: spanning tree

Load balancing NoYes


T E L E C O M

so ATM is backbone technology of choice…

but are vendor’s solutions

ready for prime-time?


T E L E C O M

StandardStandard


T E L E C O M VLAN StandardVLAN Standard

802.1q802.1q Approved IEEE draft standard for VLAN frame taggingApproved IEEE draft standard for VLAN frame tagging Expected ratification in 1997Expected ratification in 1997

802.10802.10 MAN security standardMAN security standard Implemented by router vendor Cisco over some mediImplemented by router vendor Cisco over some medi

aa

LANE 1.0LANE 1.0 Can be used as standard for VLAN interworking Can be used as standard for VLAN interworking

over ATMover ATM


T E L E C O MInternetworking Over ATM

ELAN Classical IP ATM Trunking Service PTOP(Point To Point Bridging) XLANE


T E L E C O MLAN Emulation

Decouples logical network structure from physical network topology

Split switch networks into Virtual LANs via software control

Route between virtual LANs using existing routers

Several Proprietary implementations

ATM Forum Kyoto November Meeting

First release of LAN Emulation Specification

LUNI 1.0 : LAN Emulation UNI


T E L E C O MLAN Emulation Entities

LAN Emulation Client : LECEntity in End-systems which provides a MAC level

emulated Ethernet or Token-Ring serviceLAN Emulation Server : LES

Controls coordination functions for the Emulated LANProvides a facility for registering and resolving MAC

address to ATM AddressBroadcast and Unknown Server : BUS

Handles broadcast MAC framesHandles multicast traffic

LAN Emulation Configuration Service : LECSImplements the assignment of individual LEC to

different emulated LANs


T E L E C O MConnection

Configuration Direct VCC between LEC and LECSTo obtain LES addressThis VCC could be discarded after configuration phase

Control Direct VCC between LEC and LESCarry control frames and LE_ARP requestsNever carry data frames

Data VCCs Connect the LECs to each otherConnect the LECs to the BUS


T E L E C O MLAN Emulation Stages

InitializationRegistrationAddress ResolutionData ForwardingMulticast / Broadcast


T E L E C O MRegistration / Initialization

Clients inform the LAN Emulation Server at a well-known address

Clients give their MAC address VCC established between Server and Client for Control Determine client groups

ATM

LE Server

Client

Client

Control VCC1

Control VCC2


T E L E C O M

Address Resolution / Data forwarding

ARP Request to LAN Emulation Server LE forwards to all clients of the group Allows client to establish direct VCC

ATM

LE Server

Client

Client

Data VCC

Control VCC1

Control VCC2


T E L E C O MMulticast / Broadcast

ATM Network is a NBMA network Needs Multicast Server Data for a Multicast MAC will be forwarded to members of the

group

ATM

LE Server

Client

Client

1 : MCS Address ?

MC Server

2 : Multicast Frame

3 : Forward Multicast


T E L E C O MVLAN vs. ATM ELAN

VLANVLAN Any media typeAny media type

EthernetEthernet Token ringToken ring FDDIFDDI ATMATM Frame relayFrame relay

Trunking allowedTrunking allowed ATMATM FDDIFDDI 100M Ethernet100M Ethernet Frame relayFrame relay

No server requiredNo server required

ELANELAN Media specificMedia specific

Ethernet onlyEthernet only Token ring onlyToken ring only

No trunkingNo trunking Requires central serverRequires central server


T E L E C O MVLAN Logical Network Topology

VLANs allow logical configuration independent of VLANs allow logical configuration independent of

media…media…

VLAN AVLAN A

VLAN BVLAN B


T E L E C O MPhysical Network Topology

……but, backbone and server connections are but, backbone and server connections are

increasingly ATMincreasingly ATM

ATM


T E L E C O MVLAN - ELAN Mapping

ELANS may be viewed as extensions of VLANs… ELANS may be viewed as extensions of VLANs…

for connecting to LANE attached serversfor connecting to LANE attached servers

ELAN XELAN X

ELAN YELAN Y

VLAN AVLAN A

VLAN BVLAN B


T E L E C O MClassical IP and ARP over ATM

RFC1577 : describes the initial deployment of ATM within classical IP networks : as a direct replacement for LANs for IP links which interconnect routers

The ATM host adapter is a networking interface for the IP protocol stack operating in a LAN-based paradigm


T E L E C O MRFC1577 concepts

ATM network divided in Logical IP Subnets (LIS) The same MTU is used for all VCs in the same LIS Default LLC/SNAP encapsulation of IP packets End-to-End IP routing architecture stays the same IP addresses are resolved to ATM addresses by use of

an ATMARP service within the LIS One IP subnet is used for a LIS Each VC directly connects two IP members within the

same LIS


T E L E C O MRFC1577 : LIS

ARP server in each Logical Subnet LIS : Logical IP Subnet

ATMNetwork

ARP Server 2 Subnet 2

ARP Server 1 Subnet 1

Logical Subnet 1Logical Subnet 2


T E L E C O MRFC1577 : IP Subnetwork Config

All members have the same IP network/subnet number All members within a LIS are directly connected to the AT

M network All members outside of the LIS are accessed via a router All members of a LIS must have a mechanism for resolvin

g IP addresses to ATM addresses SVC : ATM addresses to IP addresses using InATMARP PVC : ATM addresses to VC using InATMARP

All members within a LIS must be able to communicate via ATM with all other members (SVC or PVC)


T E L E C O MMandatory Client Parameters

Client ATM address ATMARP server address

NetworkATM

ARP Server LIS

AB.CDEF.01.AA4567.890A.BCDE.F012.3456.7890.1111.12

AB.CDEF.01.AA4567.890A.BCDE.F012.3456.7890.1111.11


T E L E C O MRFC1577 : Packet Format

IEEE 802.2 LLC/SNAP must be supported IEEE 802.2 LLC/SNAP is the default Other encapsulation method may be used Encapsulation will maybe be done on a per-VC

basis MTU size shall be 9180 bytes

LLC/SNAP header is 8 bytes Therefore the ATM AAL5 PDU size is 9188

bytes This is the default


T E L E C O MRFC1577 : Address Resolution

Only one ATMARP Server within the LIS Client initiates the registration to the ATMARP Server

(Point to Point VC) using the ATM address of the ARP Server

Server sends an InATMARP request to the client to build its cache table


T E L E C O MClassical IP Over ATM

Requires multiple hops for communications between different LISs

ARP Server (Subnet 1)

ARP Server (Subnet 2)

ATM Network

Registration ARP Requests

ARP Responses

Logical IP Subnet 1

Logical IP Subnet 2


T E L E C O MNext Hop Resolution Protocol

Allows communication between LISs across cloud Next-hop requests passed between next-hop server

NH servers cannot forward data Separates data forwarding paths from paths across which reachability information is passed

May lead to undetected routing loops

NHS1

NH-Requests

NHS2 NHS3

NHS4

ATM Network

Direct Connection

Next-Hop Server

LIS1 LIS2 LIS3 LIS4

NH-Reply


T E L E C O MAddress Resolution for ATM

Manual configuration Simple for early testing Administrative burden

Multicast protocols Adapt existing mechanisms Inadequate scaling

Distributed directory Various indices Complex to specify and implement

Algorithmic mapping Obstacle to network evolution


T E L E C O MRouter Evolution

Two main roles : Internetworking for existing LAN/WAN across ATM

backbones Supporting Virtual LAN internetworking

Routers will evolve into router-servers Routers also natural platform for ATM servers

LAN Emulation Server Multicast Server ARP Server Next Hop Server ConnectionLess Server


T E L E C O M

Typical switch solution & problemTypical switch solution & problem??


T E L E C O M傳統 Switch產品之建議方案

Router ATM Switch

ATM Switch

LAN Switch

ATM to the Desktop

Switched10/100 Ethernet

Switched Ethernetor Token Ring

Server


T E L E C O MThe Role of the RouterThe Role of the Router

Fully switched model

Backbone

RR


T E L E C O M The Role of the RouterThe Role of the Router

Fully switched model

Backbone

IntegratedRouting


T E L E C O M

All Switches Must Support RoutingAll Switches Must Support Routing

Inter-VLAN traffic with external router Using LANE or 802.10

ATM

RR


T E L E C O M

All Switches Must Support RoutingAll Switches Must Support Routing

Inter-VLAN traffic integrated routing

ATM

R

More efficientresource utilization


T E L E C O M

Our solution Our solution


T E L E C O M Alcatel’s ATM solution

Scalable, high performance & highly available ATM switching Building/Campus/MAN Backbones

Comprehensive, any-to-any LANswitching for tailored desktop & server solutions.

OmniSwitch

ATM NetworkLEC

1483

SVC/PVC

ELAN

LE-Services

OmniMSS

Aut

oTra

cker

Complete, high performance LAN-to-ATM internetworking services

IntelligentBroadcast Manager

Hardware RoutingEngine

NHRP

SVC/PVC

MPOA

Low cost, high performance hardware routing and optional firewalls license

Legacy WAN

DLCI

1490


T E L E C O MUser BenefitsUser Benefits

Networks deliver more bandwidth to attached devices

Networks allow user mobility

Networks provide a high level of security

Networks would be able to differentiate QoS levels among applications

Networks maintain constantly available

Networks need to scale


T E L E C O M

BandwidthBandwidthFrame + cell switchingFrame + cell switching

BandwidthBandwidthFrame + cell switchingFrame + cell switching

120

M M

ana

gem

en

t B

us

960M Frame

Bus

ATM Uplinks (34, 45, 155, 622)ATM Uplinks (34, 45, 155, 622)

Ethernet (10/100)Ethernet (10/100)

Token ringToken ring

Gigabit Ethernet UplinksGigabit Ethernet Uplinks

FDDI / CDDIFDDI / CDDI

Frame Relay / ISDNFrame Relay / ISDN

25.6M ATM25.6M ATM

155M ATM155M ATM

622M ATM622M ATM

34/45M ATM34/45M ATM

AAL-1 Circuit EmulationAAL-1 Circuit Emulation

13.2G CellBus

ManagementManagement

SARSAR


T E L E C O M

Cutover to hot standby facility in approximately 10ms

PNNI load balancing and/or 1:1 Line protection


T E L E C O M Redundant Architecture

Link Redundant Module Redundant Power Supply

Redundant


T E L E C O M

High Availability:Fault Tolerant

Architecture

Redundant power supplies Dual Cooling fans reliability Redundant management module Compatibility Passive backplane for no active components Hot-swappable modules and power supplies Distributed architecture Redundant server connections Redundant connections to an ATM switch fabric Redundant connections to hubs Fault tolerant software architecture


T E L E C O M

SERVICEdirector - Connection management


T E L E C O M

SERVICEdirector -Wizards support


T E L E C O M

Security Authenticated-user VLANsSecurity Authenticated-user VLANs

TargetVLAN 1TargetVLAN 1

AuthenticationServer

AuthenticationAgent

Logon and establish access privileges

Instruct network to connect user to target VLAN(s)

User is connected to target VLAN(s) Target

VLAN nTargetVLAN n

Firewall

Network

The Internet

11

22

33


T E L E C O MBuffer management and Traffic Management

: Throughput and QoS

Buffer management and traffic management determine: Variety of traffic types supported, e.g., from bursty LAN to iso

chronous voice and video traffic What traffic enters the network, at what rate, and whether th

e traffic gets to its destination(s) Actual throughput seen by the users Quality of service seen by the users

Important characteristics: Large, efficiently managed cell buffers Robust traffic control


T E L E C O M Current ATM switches

Existing ATM switches were developed based on the following assumptions:

there would be an even mix of voice, video and data traffic data traffic in the network would adhere to the

80/20 rule ATM end systems, such as routers, LAN switches and NICs

would behave and shape their traffic networks would be

ATM end-to-end

Departmental LANs, 80 / 20Departmental LANs, 80 / 20


T E L E C O M ATM switch requirements

New requirements for ATM switches:

massive buffer capacity

very high capacity

massive buffer capacity, policing, statistics

A mix of LAN, WAN and ATM interfaces

What has turned out to be the case:

ATM premise networks are virtually 100% bursty data

the rule is now 20/80, the majority of traffic traverses the backbone Edge devices do not shape traffic or respond to congestion indicators

Client stations are legacy LANs, the backbone is ATM


T E L E C O M An ATM solution...

The ATM Forum specifications are defined… UNI 3.1, Traffic Management 4.0, PNNI, LAN Emulation...

Unfortunately, most of today’s ATM solutions don’t... Integrate LAN, ATM and WAN access switching

Provide high throughput to handle today’s distribution of traffic, I.e., 95% bursty LAN data, and tomorrow’s

Enable scalable and highly available ATM backbone

Provide comprehensive, redundant LAN-to-ATM internetworking

Integrate low-cost, high performance routing

Support the ATM Forum standards to be a viable, long-term solution

int. ref : infraste.ppt page 1 t e l e c o m 東吳大學 二代高速校園網路工程簡報資料...

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