[c-nsp] EC flow hash computation w/MPLS

[Oliver Boehmer (oboehmer)]

Peter Rathlev <> wrote on Tuesday, January 15, 2008 6:46 PM:

> Hello,
> 
> This may be a stupid question, but I was wondering how Etherchannel
> hash calculations treat MPLS traffic: Do they dive into the packet and
> calculate hashes based on encapsulated traffic, or is it based on the
> labels?
> 
> The context is that I'm trying to find out how the WS-X6704-10GE
> compares to using Etherchannels on e.g. a WS-X6748-SFP. We're talking
> 4-5 gigs peak, maybe a gig baseline, and this number only goes up of
> course.

assuming we're talking about PFC3*, we hash on the underlying IP header
for L3VPN and "regular" LDP LSPs and on bottom label otherwise (e.g.
L2VPN/EoMPLS). PFC3 can look at most 3 labels deep for an IP header,
which should be enough for most situations.

	oli