10 Apr
2001
10 Apr
'01
8:03 p.m.
Try ~ 10ns ram which you can buy 256MB of for ~ $60-80 (www.pricewatch.com). At any rate, A raw 3 or 4 level mtrie FIB fully populated with the real 100k+ routes on the internet consumes less then 900kb, and all the interesting parts fit in the L2 cache of a Celeron A where you can do about 22,000 lookups per MHz. Hardly excessive memory bandwidth. The packet ram on the gige cards is also very fast, and could easily accomidate a dCEF approach.
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