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FIB Table and CEF Table

Hi

My question is about the difference between FIB and CEF Table.

Are they two different tables or same table that has two different names?

If they are different tables, is CEF Table created only when MPLS is enabled?

Thanks..

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Re: FIB Table and CEF Table

From the link:

http://www.cisco.com/en/US/docs/ios/12_1/switch/configuration/guide/xcdcef.html

Forwarding Information Base

CEF uses a FIB to make IP destination prefix-based switching decisions.  The FIB is conceptually similar to a routing table or information base.  It maintains a mirror image of the forwarding information contained in  the IP routing table. When routing or topology changes occur in the  network, the IP routing table is updated, and those changes are  reflected in the FIB. The FIB maintains next-hop address information  based on the information in the IP routing table.

Because there is a one-to-one correlation between FIB entries and  routing table entries, the FIB contains all known routes and eliminates  the need for route cache maintenance that is associated with switching  paths such as fast switching and optimum switching.

The article describes CEF as well.

HTH!

-Chris

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