CCIE Practical Studies: Security (CCIE Self-Study)

Chapter 11. IS-IS

This chapter includes the following topics:

• Integrated IS-IS overview

• Configuring IS-IS

• IS-IS building blocks

• The IS-IS state machine

• Pseudonodes

• IS-IS addressing

• Limiting LSP flooding

• Configuring IS-IS authentication

• Using show and debug commands

The Intermediate System-to-Intermediate System (IS-IS) link-state protocol, specified in ISO 10589, is a dynamic routing protocol designed for use with Connectionless Network Service (CLNS) to facilitate hop-by-hop path selection. IS-IS is a standard intra-domain routing protocol in the OSI protocol suite.

IS-IS provides a means to implement a hierarchical topology based on areas. Unlike OSPF, which also uses the concept of areas, IS-IS only provides two areas—Level-1 and Level-2—although ...