TCPIP and Unix

1
TCP/IP and Unix

• Chuck Davin
• University of Pennsylvania
• CSE 350
• 22 February 2001

2
Some Recent History
3
Some Recent History

• Resources
• Planning
• Dependencies
• Communication
• Knowledge

4
Engineering ? Success

• 10 to 50 Percent failure rate
• Lots of time
• Lots of money
• Classroom ? Reality

5
Audience

• Embedded Software ? User Software
• Mass-Market ? Custom

6
BSD ? TCP/IP

• API ? Protocol
• Host ? Router
• Host ? Application Gateway
• Default Router ? 0.0.0.0

7
Multihoming

• The bind () system call
• INADDR_ANY
• Defaults and Wildcards

8
BSD ? OSI

• BSD Sockets ? SVR4 Streams
• Configure IP adaptation via ifconfig
• Configure IP via routing table
• Configure TCP via bind,connect
• What is a BSD Interface?
• What is a BSD Socket?

9
BSD Sockets

• A Triumph of Abstraction
• Focus on Synchronization
• read (fd, buf, n) ! n

10
Subnets and Routing

• IP Classic was classful
• IP Subnetting introduced ca. 1986-7
• Variable Length Subnet Masks?
• Non-contiguous Subnet Masks?
• Longest Match IP Routing
• RIP, RIP2, OSPF, CLNP

11
Broader Horizons

• RFC 791 et al.
• BSD ? TCP/IP