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. > 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.) Excellent idea. Why, pray tell, then there is such things as "show cef drop" and "show cef not-cef-switched"? > The reality is that having only one copy of the routing table > creates an inevitable bottleneck. Wrong answer. Routing table != forwarding table > 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. Wrong answer again. Routing view != forwarding table > The same techniques that work to scale the Internet as a whole work inside > a box. Wrong answer again. > Why do you think central fowarding is superior to distributed forwarding? Because you will have consistency problem. You are nearly 100% guaranteed to have them. > DS Alex
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