1 chapters 2 & 3 computer networking review – the tcp/ip protocol architecture

1

Chapters 2 & 3Chapters 2 & 3

Computer Computer Networking Review Networking Review – The TCP/IP – The TCP/IP Protocol Protocol ArchitectureArchitecture

2

Chapter 2Chapter 2

Protocols, Protocols, Internetworking & Internetworking & the Internetthe Internet

Protocols, Internetworking & the Internet12

Key Features of a ProtocolKey Features of a Protocol

Set of Set of rules or conventionsrules or conventions to to exchange blocks of formatted dataexchange blocks of formatted data

SyntaxSyntax: data format: data format SemanticsSemantics: control information : control information

(coordination, error handling)(coordination, error handling) TimingTiming: order, speed matching, : order, speed matching,

sequencingsequencing ActionsActions: what happens when an : what happens when an

event occursevent occurs

Protocols, Internetworking & the Internet13

Internet Protocol Stack Internet Protocol Stack Layers (a.k.a. TCP/IP stack)Layers (a.k.a. TCP/IP stack)

PhysicalPhysicalNetwork Network

AccessAccessInternetInternetTransport Transport ApplicationApplication Physical

Link

Network

Transport

Application

or…or…

Protocols, Internetworking & the Internet14

OSI – TCP/IP Protocol StacksOSI – TCP/IP Protocol Stacks

Protocols, Internetworking & the Internet15

TCP and UDPTCP and UDP

TCP: TCP: – connection-oriented, handshake connection-oriented, handshake

requiredrequired– reliable packet delivery in sequencereliable packet delivery in sequence

UDP:UDP:– connectionless (datagram), no connectionless (datagram), no

handshakehandshake– unreliable packet deliveryunreliable packet delivery– packets may arrive out of sequence or packets may arrive out of sequence or

duplicatedduplicated

Protocols, Internetworking & the Internet16

TCP and UDP HeadersTCP and UDP Headers

TCP

UDP

Protocols, Internetworking & the Internet17

IP Headers – IPv4IP Headers – IPv4

IP Version 4 HeaderIP Version 4 Header

Protocols, Internetworking & the Internet19

Operation of TCP and IPOperation of TCP and IP IP implemented in end systems IP implemented in end systems

and routers, relaying data and routers, relaying data between hostsbetween hosts

TCP implemented for end-to-end TCP implemented for end-to-end data transfer data transfer only in end only in end systemssystems*, assuring reliable *, assuring reliable delivery of blocks of datadelivery of blocks of data

Each host on sub-network has a Each host on sub-network has a unique unique IP addressIP address

Each process on each host has a Each process on each host has a unique TCP unique TCP port numberport number

* Except when?

Protocols, Internetworking & the Internet20

TCP/IP Protocol Data Units TCP/IP Protocol Data Units (PDUs)(PDUs)

Protocols, Internetworking & the Internet22

TCP/IP ConceptsTCP/IP Concepts

Protocols, Internetworking & the Internet23

TCP ApplicationsTCP Applications

SMTP: Simple Mail Transfer SMTP: Simple Mail Transfer ProtocolProtocol

FTP: File Transfer ProtocolFTP: File Transfer Protocol telnet: remote logintelnet: remote loginHTTP: web browsingHTTP: web browsing

Inelastic or Elastic?Inelastic or Elastic?

Protocols, Internetworking & the Internet24

TCP ApplicationsTCP Applications

FTPclient

FTPserver

TCP control connection

port 21

TCP data connectionport 20

mailserver

useragent

useragent

useragent

mailserver

useragent

useragent

mailserver

useragent

SMTPSMTP

SMTPSMTP

SMTPSMTPPC runningPC running

ExplorerExplorer

Server Server runningrunning

Apache WebApache WebServerServer

Mac runningMac runningNavigatorNavigator

http request

http re

quest

http response

http re

sponse

email

Web browsing

file transfer

Protocols, Internetworking & the Internet26

RoutersRouters

Provide link between networksProvide link between networksAccommodate network Accommodate network

differences:differences:– Addressing schemesAddressing schemes– Maximum packet sizesMaximum packet sizes– Hardware and software interfacesHardware and software interfaces– Network reliabilityNetwork reliability

– Congestion/Traffic ManagementCongestion/Traffic Management

Protocols, Internetworking & the Internet27

TCP/IP Internetworking TCP/IP Internetworking ExampleExample

Protocols, Internetworking & the Internet28

Figure 2-8Figure 2-8

Protocols, Internetworking & the Internet29

Figure 2-9Figure 2-9

Protocols, Internetworking & the Internet30

Figure 2-10Figure 2-10