Understanding Routing

The following table outlines the CCNA exam objectives that are reviewed in this chapter. The numbers shown correspond to the master list of objectives found in Chapter 1, “What Is CCNA?”

1. Although listed as an objective covered in this chapter, objective 43 is much better placed in this book with the discussion contrasting segmentation using bridges and switches, so that objective is covered in Chapter 4.

This book is organized into chapters based on the organization of the CCNA objectives as defined by Cisco Systems. This chapter matches the CCNA objectives organization topic titled simply “Routing.” The objectives in this topic are actually better described as routing protocols—the protocols used to create routes in a routing table. Routing generally refers to the work a router does when deciding how to forward an individual packet. For a more complete discussion of the terms routing and routing protocol, please refer to Chapter 3, “Understanding the OSI Reference Model.”

This chapter starts with an examination of routing protocol concepts then reviews IGRP and IP RIP configuration. A discussion of IPX RIP, SAP, and GNS follows. SAP and GNS are not specifically mentioned in the objectives, other than for SAP filtering, but a review is needed; it is included in this chapter. Finally, the chapter concludes with an explanation of objective 41: the services of separate and integrated multiprotocol routing.