Computer Architecture II: Specialized 0909.444.01/02 Fall 2001

1
Computer Architecture II Specialized0909.444.01
/02 Fall 2001
Lecture 3November 1, 2001

• John L. Schmalzel
• Shreekanth Mandayam
• ECE Department
• Rowan University
• http//engineering.rowan.edu/shreek/fall01/compar
  ch2/

2
Plan

• Data Processing Data Communications
• Communications Networks
• Packet Switched Networks
• Why are we interested in this?
• What are we studying here?
• Protocols Protocol Architecture
• OSI 7-Layer Protocol Architecture
• TCP-IP Protocol Architecture

3
Communications Networking
Recall
4
TDM Circuit Switching
Recall
Message 1
Quantize Encode
Message 2
Channel
Message N
Message 1
LPF
Message 2
LPF
Message N
LPF
5
Recall Packet Switching
Recall
Depacket-izing
Message 1
Message 1
Depacket-izing
Packetizing
Message 2
Message 2
Message 3
Depacket-izing
Message 3
6
Why are we studying this?
ROUTER
COM
OS






Memory

• What?
• Protocol
• Data
• Frequency

7
Protocols
8
A 3-Layer Protocol Architecture
Files and file transfer commands
File transfer application
Communications service module
Network access module
File transfer application
Communications service module
Network access module
Comm related messages
Comm network
Computer 1
Computer 2
9
ISO OSI 7-Layer Model
ASIDE
Please Do Not Touch Steves Pet Alligator !!!
10
TCP-IP Protocol Architecture
11
TCP-IP Operation Example
Port or Service access point (SAP)
Logical connection (TCP)
Global network address
Subnetwork attachment point address
Logical connection
Router J
IP IP
NAP1 NAP2
Network 1
Network 2
12
TCP-IP Protocol Packet
13
IP Header
0 4 8
16 19
31
Version IHL Type of Service Total Length Total Length
Identification Identification Identification Flags Fragment Offset
Time to Live Time to Live Protocol Header Checksum Header Checksum
Source Address Source Address Source Address Source Address Source Address
Destination Address Destination Address Destination Address Destination Address Destination Address
Options Padding Options Padding Options Padding Options Padding Options Padding
20 octets
14
TCP Header
0 4 10
16
31
Source Port Source Port Source Port Source Port Source Port Source Port Source Port Source Port Destination Port
Sequence Number Sequence Number Sequence Number Sequence Number Sequence Number Sequence Number Sequence Number Sequence Number Sequence Number
Acknowledgement Number Acknowledgement Number Acknowledgement Number Acknowledgement Number Acknowledgement Number Acknowledgement Number Acknowledgement Number Acknowledgement Number Acknowledgement Number
Data Offset Reserved URG ACK PSH RST SYN FIN Window
Checksum Checksum Checksum Checksum Checksum Checksum Checksum Checksum Urgent Pointer
Options Padding Options Padding Options Padding Options Padding Options Padding Options Padding Options Padding Options Padding Options Padding
20 octets
15
Summary
16
References

• William Stallings, Data and Computer
  Communications, 5th Edition, Prentice-Hall, 1997.
  
• Jean Walrand, Communication Networks, 2nd
  Edition, WCB/McGraw-Hill, 1998.