The following topics are covered in this chapter:
IP routing is essentially the process of moving packets from one network to another network via routers. To be able to forward packets, routers need an accurate map of their internetworks to refer to, called a routing table. Routing tables can be creating manually, a process known as static routing, but going with this method is a lot of work—especially if you’re dealing with a decent sized network! The much easier alternative is dynamic routing, which uses protocols to find networks and update routing tables. But in networking as in life, there’s no free lunch, and dynamic routing will cost you in bandwidth on your network’s links as well as in router CPU processing.
Routing protocols define the set of rules used by a router when it communicates routing information between neighboring routers.
The first dynamic routing protocol I’m going to cover is Routing Information Protocol, or RIP, versions 1 and 2. RIP is only used in small networks now.
Enhanced Interior Gateway Routing Protocol (EIGRP) is a Cisco protocol that predictably runs on Cisco routers and is very important because it’s one of the two most popular routing protocols in use today. We’ll explore some of the features of EIGRP, and then I’ll describe how it works and demonstrate how to configure ...