IP Routing

Organization

This book is comprised of eight chapters:

Chapter 1

This chapter introduces the basic concepts of IP routing. It will show you the simplest method of creating entries in a routing table -- by defining static routes.

Chapter 2

RIP is the earliest dynamic routing protocol. This chapter describes RIP in detail, including a discussion of the Distance Vector (DV) algorithms that are the foundation of RIP and other routing protocols. Since RIP is the simplest dynamic routing protocol, it is a great tool from which to learn. It may be a good idea to study this chapter even if you do not intend to use RIP.

Chapter 3

IGRP is Cisco’s proprietary routing protocol, which directly descended from RIP. IGRP contains some features that make it much more useful than RIP. This chapter focuses on these new features (study Chapter 2 to learn about the foundations of IGRP -- the DV protocols).

Chapter 4

The DV algorithms employed by RIP and IGRP have inherent limitations. EIGRP is Cisco’s proprietary routing protocol, which interworks seamlessly with IGRP but attempts to overcome these limitations. EIGRP supports classless networks and Variable Length Subnet Masks (VLSM).

Chapter 5

RIP-2 is an attempt to bring RIP back into vogue. RIP-2 is really RIP with support for classless networks and VLSM. RIP-2 still has all the limitations of DV protocols, such as long convergence times.

Chapter 6

OSPF is an open routing protocol. It is most commonly used to build large IP networks. The standards bodies are focusing their work on OSPF, and it is constantly evolving. OSPF is not a DV protocol: OSPF is based on the Dijkstra algorithm. This chapter explains Dijkstra in detail and lays the foundation of how to build hierarchical networks using OSPF.

Chapter 7

BGP is the glue that binds the thousands of networks that comprise the Internet. Routing in the Internet is quite different from routing in intranets. There are several new concepts in this chapter.

Chapter 8

This chapter describes the administrative tools available to all the routing protocols. These tools are used to block the advertisement of routing updates, set up preferences for one routing protocol over another, and more.