mailing list archives
Re: Internet Backbone Index
From: "Dorian R. Kim" <dorian () blackrose org>
Date: Sun, 13 Jul 1997 16:38:44 -0400 (EDT)
On Thu, 10 Jul 1997, Gary Zimmerman wrote:
NAP? Where is most of the packet lost on the internet? MAEs and NAPs.
Where does most of the latency come from? Routers. MAEs and NAPs are
I only have one more question for you; how many router hops, on your
network, from New York to Los Angeles? If it is more than 1, then tell me
what your latency is from end to end. Let's compare, shall we.
I was going to ignore this particular pissing contest, but this caught my eye.
I heard from some people that there are customers who complain about the
number of IP hops through a network, and didn't get why they would ask such an
irrelevant question, but now I see why.
For the Nth time, routers by themselves do _NOT_ introduce any significant
increased latency over switches, and whatever amount that may be is dwarfed by
the propagation delay of long haul circuits.
If argue otherwise is just silly marketing stunt.
Now, there are failure modes in which routed networks can add large amounts of
latency to flows. However, I can think of just as many failure modes in
switched networks that will do the same.
There are many valid reasons why you'd want to build a switched WAN backbone
as opposed to a routed one in the current environment. However, to argue that
a switched backbone has an inherent advantage over a routed one is at best
disingenuous, and at worst dishonest.
- Re: Internet Backbone Index, (continued)