TCP/IP Guide

OSPF General Operation

As a routing protocol, the main job of OSPF is to facilitate the exchange of routing information between routers. Each router in an OSPF AS that runs OSPF software is responsible for various tasks, such as setting timers to control certain activities that must occur on a regular basis, and the maintenance of important data structures, such as the LSDB. Most important, each OSPF router must both generate and respond to OSPF messages. It is this messaging system that allows important routing information to be shared within an AS or area, which makes it crucial to understanding how OSPF works. So it's worth starting a discussion of OSPF operation by taking a look at the message types and how they are used.

OSPF Message Types ...