Configuring Integrated IS-IS

Integrated IS-IS is unique among the IP routing protocols covered in this book for a couple of reasons. First, it is the only protocol that must be enabled both as a process and on individual interfaces. Second, it is the only IP routing protocol that was not originally designed for IP. Because Integrated IS-IS uses CLNS PDUs rather than IP packets, the configuration is not always as obvious as that of the other protocols.

An interesting side effect of the fact that Integrated IS-IS is a CLNS protocol is that the IP addresses of neighboring routers have no influence on the formation of adjacencies. As a result, IS-IS does not have the adjacency restrictions concerning secondary IP addresses that OSPF has. However, ...

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