TCP/IP

1. Chapter 2
Protocols and the TCP/IP Suite
Chapter 2 Protocols and the TCP/IP Suite 1

2. Introduction
• Layered protocol architecture
• TCP/IP protocol suite
• OSI reference model
• Internetworking
Chapter 2 Protocols and the TCP/IP Suite 2

3. The Need for a Protocol Architecture
• Procedures to exchange data between devices
can be complex
• High degree of cooperation required between
communicating systems
Chapter 2 Protocols and the TCP/IP Suite 3

4. Example: File transfer
• Requires a data path to exist
• Tasks:
– Activate data communication path
– Source determines that destination is ready
– File transfer app destination file management app
is ready store file for user
– File format conversion
Chapter 2 Protocols and the TCP/IP Suite 4

5. 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
Chapter 2 Protocols and the TCP/IP Suite 5

6. Key Features of a Protocol
• Set of rules or conventions to exchange blocks
of formatted data
• Syntax: data format
• Semantics: control information (coordination,
error handling)
• Timing: speed matching, sequencing
Chapter 2 Protocols and the TCP/IP Suite 6

7. TCP/IP Layers
• Physical
• Network access
• Internet
• Transport Application
Chapter 2 Protocols and the TCP/IP Suite 7

8. 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
Chapter 2 Protocols and the TCP/IP Suite 8

9. Figure 2.1
Chapter 2 Protocols and the TCP/IP Suite 9

10. Figure 2.2
Chapter 2 Protocols and the TCP/IP Suite 10

11. 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
Chapter 2 Protocols and the TCP/IP Suite 11

12. Figure 2-3
Chapter 2 Protocols and the TCP/IP Suite 12

13. Figure 2-4
Chapter 2 Protocols and the TCP/IP Suite 13

14. TCP Applications
• SMTP: Simple Mail Transfer Protocol
• FTP: File Transfer Protocol
• telnet: remote login
Chapter 2 Protocols and the TCP/IP Suite 14

15. OSI Reference Model
• Application
• Presentation
• Session
• Transport
• Network
• Data link
• physical
Chapter 2 Protocols and the TCP/IP Suite 15

16. Figure 2.5
Chapter 2 Protocols and the TCP/IP Suite 16

17. Internetworking Terms
• Communication network
• Internet
• Intranet
• Subnetwork
• End system
• Intermediate system
• Bridge
• Router
Chapter 2 Protocols and the TCP/IP Suite 17

18. Routers
• Provide link between networks
• Accommodate network differences:
– Addressing schemes
– Maximum packet sizes
– Hardware and software interfaces
– Network reliability
Chapter 2 Protocols and the TCP/IP Suite 18

19. Figure 2-7
Chapter 2 Protocols and the TCP/IP Suite 19

20. Figure 2-8
Chapter 2 Protocols and the TCP/IP Suite 20

21. Figure 2-9
Chapter 2 Protocols and the TCP/IP Suite 21

22. Figure 2-10
Chapter 2 Protocols and the TCP/IP Suite 22