Jon Marshall Wed, 06/06/2007 - 03:10
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It turns on CEF switch (CEF = Cisco Express Forwarding).

Attached is an introductory paper on different switching types you can use with Cisco. There is a section on CEF.



bvsnarayana03 Wed, 06/06/2007 - 05:11
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Switching methods that routers use, define the way how pkts are handled by router. There are 3 methods:

Process Switching: legacy switching type. Each & evry pkt does a routing lookup to find reachability to destination, next-hop, & the interface from where next-hop is available.

Fast Switching: 1st pkt is process switched. Stores the info in a cache, thus reduce the router lookup time for following pkt to same destination. The cache info is timed out at regular intervals.

CEF: no process switching for 1st pkt. Router builds 2 tables, cef table that defines reachability of network, & adjacenccy table to define the next-hop & interface via which nxt-hop is reachable. Cache is not aged out.


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