[f-nsp] NetIron MLX Experience..

[Joseph Jackson]

> 
> 
> On Tue, 8 Aug 2006, Richard A Steenbergen wrote:
> 
> ...
> > Yes the new generation of gear uses a prepopulated CAM as a FIB by 
> > default (marketing name FDR, same as Cisco CEF), though there is an 
> > option to turn it off and do fast-cache type behavior, or use the 
> > traditional dr/net-agg cam aggregation.
> ...
> 
>    Strictly speaking, Cisco CEF is just a way to store a 
> forwarding table for fast lookups.  The storage could be in 
> some kind of content addressable memory, and looked up by an 
> ASIC, or it could be in RAM and looked up by the the router's CPU.
> 
>    Even Cisco 26xx routers support CEF now, even though this 
> is purely a software device driven device.  You just have to 
> pay the cost of storing both the routing table, and the CEF 
> FIB in RAM.
> 
>    So Foundry made the jump to putting the full routing table 
> in CAM with the MLX?  Juniper has always operated this way, 
> so why have some respondants talked about replacing Juniper's 
> with MLXs?  Other than that some of the old processing 
> engines on the Juniper's lacked enough memory for some 
> features, there should be little difference at the L2/L3 
> forwarding level these days?
> 
> 

Foundry does NOT store the full routing table in the FIB it only stores
the most specific.  The way I understand it, (as explained to me by a
foundry SE).  Is that any changes to the RIB get populated to the FIB
only if a more specific route is found.