Saku Ytti wrote: > On (2008-11-30 19:28 -0500), Julio Arruda wrote: > >> I was under impression the L3 forwarding and the L2 forwarding was done >> by the same engine, in the PFC card(s) ? and behind it, the EARL for the >> lookup and the rewriting of the header info (mac rewrite, dec ttl and >> goes on) ? > > Inside PFC/EARL you have Tycho for L3 and Superman for L2. Or > one cost reduced version called Supertycho (with bus chip functionality > separated to dedicated chip called Kuma) in 3C and up (prolly > nexus too then).
Nexus 7000 run a newer generation of the PFCx ASIC which allows for vlan uniqueness per port. Ian > >> That is how Nortel 8600 (and earlier gen, rapidcity-legacy) did the >> work, the same lookup engine would do l2 and l3, so I may be messing up >> things in my mind :-), in a little more distributed fashion (more like >> DFCs) > > Dunno if this true, prolly depends how deep inside the die you look. > Also not sure what relevance there is if L2/L3 lookup is in one engine > or several engines. In my mind at least it's not advantage or disadvantage > for consumer, except for the fewer dies you have, the cheaper > it is to produce (better yields) and less power will probably > be dissimulated as heat. > _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
