Routing Interchange Protocol
In the days before intelligent routers, this was the basic way for routers to tell each other what they were doing. The whole point of IP was redundancy, as in multiple routes from A to B, so that if some of the intermediate points got nuked, data could still flow by a rearrangement of routes. For this to work, routers have to know what their neighbors are doing.
RIP works via a periodic broadcast mechanism, like NetBIOS. The problem with this is - if something major gets horked, it can take a long time for the network to stabilize.
The modern solution is called OSPF, "Open Shortest Path First", which uses a completely different base algorithm that settles down rapidly in case of major horkings.
Here's an introduction:
[link|http://www.networkcomputing.com/unixworld/feature/002.html|http://www.networkco.../feature/002.html]
