North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical RE: gigabit router (was Re: Getting a "portable" /19 or /20)
> CEF should be called Customer Enrangement Feature. It is a very very very > bad idea to have linecards be anything else than forwarders. They > should not > make any intelligent routing decisions. There should not be a > tons of copies > of routing table on line cards. That is what creates problems. > > Alex CEF allows linecards to be forwarders. They don't make any routing decisions, they just forward packets according to a routing table. (Routing = deciding where packets should go, ie building a routing table. Forwarding = sending packets to their destination, ie using a routing table.) The reality is that having only one copy of the routing table creates an inevitable bottleneck. For the same reasons this won't work on a regional network, it won't work on a single router if the router is sufficiently complex. The same techniques that work to scale the Internet as a whole work inside a box. Why do you think central fowarding is superior to distributed forwarding? DS
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