University of MysoreDos in Library and Information Science

Seminar Topic:“Network protocol”

Presented To,Prof. Chandrashekar

M.Dos in LISc

Presented by,Swamy nayaka C K2nd year MLIScDos in LISc

Network Protocol A protocol is a set of rules that governs the

communications between computers on a network. These rules include guidelines that regulate the following characteristics of a network: access method, allowed physical topologies, types of cabling, and speed of data transfer.

What is a Protocol?Protocol is a controlled sequence of

messages that is exchanged between two or more systems to accomplish a given task.

Protocol specifications define this sequence together with the format or layout of the messages that are exchanged.

DefinitionA communications protocol is a system of

digital rules for message exchange within or between computers. Communicating systems use well-defined formats for exchanging messages. Each message has an exact meaning intended to provoke a particular response of the receiver. ...

History The Internet protocol suite resulted from research and

development conducted by the Defense Advanced Research Projects Agency (DARPA) in the late 1960s. After initiating the pioneering ARPANET in 1969, DARPA started work on a number of other data transmission technologies. In 1972, Robert E. Kahn joined the DARPA Information Processing Technology Office, where he worked on both satellite packet networks and ground-based radio packet networks, and recognized the value of being able to communicate across both. In the spring of 1973, Vinton Cerf, the developer of the existing ARPANET Network Control Program (NCP) protocol, joined Kahn to work on open-architecture interconnection models with the goal of designing the next protocol generation for the ARPANET.

Protocol developmentFor communication to take place, protocols

have to be agreed upon. Recall that in digital computing systems, the rules can be expressed by algorithms and data structures, raising the opportunity of hardware independence. Expressing the algorithms in a portable programming language, makes the protocol software operating system independent. The source code could be considered a protocol specification. This form of specification, however is not suitable for the parties involved.

Common types of protocolsThe Internet Protocol is used in concert with

other protocols within the Internet Protocol Suite. Prominent members of which include:

Transmission Control Protocol (TCP)User Datagram Protocol (UDP)Internet Control Message Protocol (ICMP)Hypertext Transfer Protocol (HTTP)Post Office Protocol (POP)File Transfer Protocol (FTP)Internet Message Access Protocol (IMAP)

Types of Network Protocols

Ethernet Local Talk Token Ring FDDI ATM

Ethernet The Ethernet protocol is by far the most widely used. Ethernet uses an access method called CSMA/CD (Carrier Sense Multiple Access/Collision Detection). This is a system where each computer listens to the cable before sending anything through the network.

Local Talk Local Talk is a network protocol that was developed by Apple Computer, Inc. for Macintosh computers. The method used by Local Talk is called CSMA/CA (Carrier Sense Multiple Access with Collision Avoidance). It is similar to CSMA/CD except that a computer signals its intent to transmit before it actually does so. Local Talk adapters and special twisted pair cable can be used to connect a series of computers through the serial port.

Token Ring The Token Ring protocol was developed by

IBM in the mid-1980s. The access method used involves token-passing. In Token Ring, the computers are connected so that the signal travels around the network from one computer to another in a logical ring. A single electronic token moves around the ring from one computer to the next.

FDDI Fiber Distributed Data Interface (FDDI) is a

network protocol that is used primarily to interconnect two or more local area networks, often over large distances. The access method used by FDDI involves token-passing. FDDI uses a dual ring physical topology.

ATM Asynchronous Transfer Mode (ATM) is a

network protocol that transmits data at a speed of 155 Mbps and higher. ATM works by transmitting all data in small packets of a fixed size; whereas, other protocols transfer variable length packets. ATM supports a variety of media such as video, CD-quality audio, and imaging. ATM employs a star topology, which can work with fiber optic as well as twisted pair cable.

Benefits Communicating over a network is a complicated task.

Different hardware elements in the network need to be informed of the process in hand and instructed in their role. Each element has its own requirements and a set format for receiving instructions. Both the sender and receiver must communicate in the same language and all connecting hardware and software must be able to exchange control information. The benefits of using network protocols are that all these tasks have already been mapped out by someone else, and they have published their knowledge for others to share.

NeedsHuman intercommunication (in pairs or

larger groups) requires rules of conversation (do not speak if someone else is speaking) to function effectively.

Computers are no different. Consider the following simplistic analogy:

Therefore, we need regulations and rules to how we communicate over a computer network. For example to remote login (telnet), FTP or email.

The set of rules and regulations is called a Protocol.

Functions The function of protocols in a network and how

each protocol works in one or more layers of the open systems interconnection (OSI) model, why protocols are needed to enable computer communications, and describe common protocol suites.

ObjectivesAppreciate the role of measurement in

building and maintaining high-performance TCP/IP networks

Explain the types of tools available for performance measurement

Familiarize with freely available performance measurement and testing tools

Select an appropriate tool for a given task

Advantages1. Many computers from all the world can connect together, because they are using the international standard.

2. Easier maintenance and installation because you get used on the standard.

Disadvantages1. Problems Occur in Standards, it will be international problem.

2. All companies and manufactures must follow the standards instead of developing new techniques.

CONCLUSIONWhile the age-old concept of the network is

foundational in virtually all areas of society, Computer Networks and Protocols have forever changed the way humans will work, play, and communicate. Forging powerfully into areas of our lives that no one had expected, digital networking is further empowering us for the future. New protocols and standards will emerge, new applications will be conceived, and our lives will be further changed and enhanced.