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New Member

cef performance

I have some questions from one of my customer, i would be grateful if any one could help with some inputs.

1. What is generally the difference in throughput when CEF function is used, and the case where it is not used on a cisco7200?

( can we specify the performance difference in % )

2. What are the merit and demerit of using CEF on the following :

a.Access List


( i have read that though cef is configured, the initial packet for nat and access-list are process switched)

Any information provided on the above would be of great help and highly appreciated.


Re: cef performance

I can address 2.b. from experinece. We were having painfully slow response, etc with cef enabled on a nat router. When we disabled cef life was good again.

New Member

Re: cef performance

For throughtput issue, it depends on many factors such as traffic load, and the size of routing table. Basically if CEF is turned on, router will use binary search on the routing table rather than sequencial search.

Just think about binary search tree VS. sequencial search. Which one is better if your table contain for example 100,000 entries

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