3com S7906E Manuel De Montage
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IS-IS Configuration
When configuring IS-IS, go to these sections for information you are interested in:
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The term “router” in this document refers to a router in a generic sense or an Ethernet switch running
routing protocols.
IS-IS Overview
Intermediate System-to-Intermediate System (IS-IS) is a dynamic routing protocol designed by the
International Organization for Standardization (ISO) to operate on the connectionless network protocol
(CLNP).
The IS-IS routing protocol was modified and extended in RFC 1195 by the International Engineer Task
Force (IETF) for application in both TCP/IP and OSI reference models, and the new one is called
Integrated IS-IS or Dual IS-IS.
IS-IS is an Interior Gateway Protocol (IGP) used within an Autonomous System. It adopts the Shortest
Path First (SPF) algorithm for route calculation.
Basic Concepts
IS-IS terminology
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Intermediate system (IS). An IS, similar to a router in TCP/IP, is the basic unit in IS-IS to generate
and propagate routing information. In the following text, an IS refers to a router.