Fast switching builds a forwarding cache on the fly, based on the packets that reach the router and need to be switched. CEF builds the "cache" (CEF table) based on the routing table, independently from the traffic.
The fast switching cache does not (necessarily) contain all the information that's in the routing table; it starts out empty and entries are aged out of it later on. Consequently the first packet of every new "session" going through the router must be process switched, ie. a routing table lookup and cache population need to take place before the packet can be forwarded. The CEF table always contains all the information that the router has access to, it changes (almost) immediately after the router receives a routing update. Thanks, Zsombor At 03:17 AM 7/3/2003 +0000, wj chou wrote: >Can anyone tell me what's the difference between fast switching and cef >switching? > >thanks first! > >Ellie Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=71831&t=71815 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
