Integrated IS-IS

Integrated IS-IS
THE CCNP EXAM TOPICS COVERED IN THIS
CHAPTER INCLUDE THE FOLLOWING:


Understand OSI terminology and Network layer protocols
used in OSI.


Be able to compare IS-IS and OSPF.


Know the different types of IS-IS routers and their role in
IS-IS area design.


Understand why IS-IS uses a hierarchical topology.


Know how IS-IS establishes adjacencies.


Understand how to configure and verify IS-IS.

You may be interested to learn that there are other link-state routing
protocols in existence besides OSPF. One of these routing protocols
is known as Intermediate System to Intermediate System
(IS-IS). In fact, IS-IS is based on yet another link-state routing protocol from Novell—the Netware
Link Services Protocol (NLSP).
The goal of this chapter is to raise your knowledge of IS-IS to the level of knowledge you have
for OSPF. This chapter begins with a brief history of IS-IS, followed by a description of the operation
of IS-IS. After you feel comfortable with the operation of IS-IS, we will move on to the configuration
of IS-IS in an internetwork. This chapter concludes by exploring the methods available
to verify proper operation of IS-IS and how to troubleshoot it if it is not operating properly.
By the time you complete this chapter, you should have a thorough understanding of the
fundamentals behind IS-IS. You will also be able to implement it in a real-world network.
Pay attention to the details covered in this chapter, because IS-IS will introduce new concepts
that you may not be familiar with, such as Connectionless Network Services (CLNS).