Chapter 2 of the document focuses on protocols and the TCP/IP suite, covering topics such as the architecture of high-speed networks, the functioning of TCP and IP, and network management issues like congestion control and quality of service. It outlines the layered structure of protocols, detailing how these layers interact and the essential features needed for effective communication. The chapter also highlights the importance of routers in internetworking between different subnetworks and provides specific examples of TCP applications.

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Chapter 2 Protocols and the TCP/IP Suite
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2. Course Objective
 Introducing high speed networks including
gigabit networks.
 Design issues related to IP and TCP/IP and ATM
networks
 Provide up-to-date survey of developments in the
area.
 Performance analysis, congestion control and
provision of QoS to different applications are
also discussed.
Chapter 2 Protocols and the TCP/IP Suite
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3. Course Outline
 Protocols and the TCP/IP Suite
 TCP and IP
 Frame Relay
 Asynchronous Transfer Mode
 High-Speed LANs
 Queuing Analysis
 Congestion and Traffic Management
 Internet Routing
 Assignment on Different Protocols in
Networking
Chapter 1 Protocols and the TCP/IP Suite
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Chapter 1
Protocols and the TCP/IP Suite

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Introduction
 Layered protocol architecture
 TCP/IP protocol suite
 OSI reference model
 Internetworking

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The Need for a Protocol
Architecture
 When computers, terminals and/or other data
processing devices exchange data:
– The Procedures involved to exchange data
between devices can be complex
– High degree of cooperation required between
communicating systems
 See the example in the next slide.

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Example: File transfer
 Requires a data path to exist (either a direct link
or via a comm. network)
 Tasks:
– Activate data communication path
– Source determines that destination is ready
– File transfer app at source must ascertain that destination file
management app is ready to store file for user
– File format conversion
 Instead of implementing the logic as a single module, the
task is broken up into subtasks, each of which is
implemented separately.

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Layered Protocol Architecture
 Modules arranged in a vertical stack
 Each layer in stack:
– Performs related functions
– Relies on lower layer for more primitive functions
– Provides services to next higher layer
– Communicates with corresponding peer layer of
neighboring system using a protocol
 Ideally, layers should be defined, so that changes in
one layer do not require changes in other layers.

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Key Features of a Protocol
 It takes two to communicate – the same set of layered
functions must exist in two systems – peer layers.
 The peer layers communicate by means of formatted
blocks of data that obey a set of rules or conventions
known as a protocol.
 The key features of a protocol are as follows:
– Set of rules or conventions to exchange blocks of
formatted data
– Syntax: concerns the format of the data blocks
– Semantics: Includes control information (coordination,
error handling)
– Timing: speed matching, sequencing

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TCP/IP Layers
 Physical – concerned with specifying the
characteristics of the transmission medium, the
nature of the signals, the data rate and related
matters.
 Network access – concerned with the exchange of
data b/n an end system and the network to which it is
attached.
 Internet
 Transport
 Application

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TCP and UDP
 TCP:
– connection-oriented
– Reliable packet delivery in sequence
 UDP:
– connectionless (datagram)
– Unreliable packet delivery
– Packets may arrive out of sequence or
duplicated

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Figure 2.1

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Figure 2.2

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Operation of TCP and IP
 IP implemented in end systems and
routers, relaying data between hosts
 TCP implemented only in end systems,
assuring reliable delivery of blocks of data
 Each host on subnetwork has unique IP
address
 Each process on each process has unique
IP port number

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Figure 2-3

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Figure 2-4

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TCP Applications
 SMTP: Simple Mail Transfer Protocol
 FTP: File Transfer Protocol
 telnet: remote login
 HTTP(s)

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OSI Reference Model
 Application
 Presentation
 Session
 Transport
 Network
 Data link
 physical

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Figure 2.5

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Internetworking Terms
 Communication network
 Internet
 Intranet
 Subnetwork
 End system
 Intermediate system (IS)
 Bridge – an IS used to connect two LANs that
use similar LAN protocols. (an Address
Filter)
 Router – an IS used to connect two networks
that may or may not be similar.

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Routers
 Internetworking among dissimilar
subnetworks is achieved by using routers to
interconnect the subnetworks.
 Provide link between networks
 Provide for the routing and delivery of data
 Accommodate network differences:
– Addressing schemes
– Maximum packet sizes
– Hardware and software interfaces
– Network reliability

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Figure 2-7

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Figure 2-8

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Figure 2-9

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Figure 2-10