[53202] in North American Network Operators' Group
number of hops != performance
daemon@ATHENA.MIT.EDU (Mikael Abrahamsson)
Tue Nov 5 12:14:15 2002
Date: Tue, 5 Nov 2002 18:13:37 +0100 (CET)
From: Mikael Abrahamsson <swmike@swm.pp.se>
To: nanog@merit.edu
Errors-To: owner-nanog-outgoing@merit.edu
We have competitors that are claiming that their network is superior to
ours (salesdroids to customers) because they have fewer L3 hops in their
network. I see this "fact" pop up in customer questions all the time.
I can see that L3 hops adds latency if a network is built on slow (2meg
for instance) links, but at gigabit speeds, L3 hops adds microseconds in
latency (if you use equipment that forward using hardware-assisted
forwarding, but as far as I know there are no routers out there nowadays
that doesnt).
Does anyone have a nice reference I can point to to once and for all state
that just because a customer has 6-8 L3 hops within our network (all at
gigabit speeds or higher) that doesnt automatically mean they are getting
bad performance or higher latency.
Hiding the L3 hops in a MPLS core (or other L2 switching) doesnt mean
customers are getting better performance since equipment today forwards
just as quickly on L3 as on L2.
--
Mikael Abrahamsson email: swmike@swm.pp.se
