Link State Routing

COMP 431 Internet Services & Protocols The Network Layer: Routing & Addressing

Kevin Jeffay

Department of Computer Science University of North Carolina at Chapel Hill jeffay@cs.unc.edu

March 26, 2012

http://www.cs.unc.edu/~jeffay/courses/comp431

©2012 by Kevin Jeffay

1

The Network Layer: Routing & Addressing

Outline Network layer services Routing algorithms

» Least cost path computation algorithms

application transport network link physical

Hierarchical routing

» Connecting networks of networks

IP Internet Protocol

» Addressing » IPv6

Routing on the Internet

» Intra-domain routing » Inter-domain routing

Router architecture

©2012 by Kevin Jeffay

application transport network link physical

2

The Network Layer

Network layer functions Application-layer protocols define when and how Logical end-to-end messages are sent

transport application transport network link physical

network link physical

Physical endto-end packet delivery

network link physical network link physical

Transport-layer protocols deliver data between processes on different end-systems

» Transport protocols execute only on end systems

network link physical

network link physical

network link physical

network link physical

Network-layer protocols deliver data from one endsystem to another

» Network layer protocols execute on every end-system and router

©2012 by Kevin Jeffay

network link physical

application transport network link physical

3

The Network Layer

Network layer functions The network-layer provides four important functions:

» Addressing: the means by which end systems identify and transmit data to each other » Path determination: the route taken by packets from source to destination » Switching: the movement of packets from an input interface to an appropriate output interface » Call setup: The establishment of a virtual circuit from sender to receiver

©2012 by Kevin Jeffay

application transport network link physical...