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RE: a radical proposal (Re: protocols that don't meet the need...)
From: "Ejay Hire" <ejay.hire () isdn net>
Date: Wed, 15 Feb 2006 14:53:23 -0600


I like this idea, and your argument about simplifying the
forwarding plane makes sense.  
Should every edge node speak the EGP, or is be static from
the NSP?  My assumption is that they'll generally be static
from the NSP, unless multihomed to keep from exchanging
routing information about 2^32 prefixes.

-ejay

-----Original Message-----
From: owner-nanog () merit edu [mailto:owner-nanog () merit edu]
On 
Behalf Of Andre Oppermann
Sent: Wednesday, February 15, 2006 2:42 PM
To: Edward B. DREGER
Cc: nanog () merit edu
Subject: Re: a radical proposal (Re: protocols that don't 
meet the need...)


Edward B. DREGER wrote:
CA> Date: Wed, 15 Feb 2006 14:04:24 -0600
CA> From: Chris Adams

CA> There's a difference: computers (routers) handle the

O(N^2) routing
CA> problem, while people would have to handle the
O(N^2) 
cooperative AS
CA> problem.

0.1 ^ 2 < 5000

One must also consider the scalar coefficient.

Err, the problem is not the number of AS numbers (other
than having to
move to 32bit ones).  The 'problem' is the number of
prefixes in the
routing system.  The control plane scales rather well and
directly
benefits from Moore's law.  With todays CPU's there is no
problem
handling 2 million routes and AS numbers.  Absolutely not.

Things get a bit more hairy with the forwarding plane
though.  The
faster the link speed the less time it has per lookup and
the larger
the routing table the more routes it has to search in that

ever shrinking
amount of time.

You see, saving on AS numbers is not really going to help 
much where it
matters.

IMHO, and I have stated this before, the best way to
handle the route
issue is to hand out IPv6 /32 for multihoming and make it
the 
routeable
entity.  Perfect matches in hardware are pretty easy to do
for large
numbers of them compared to longest match.  On the plus
side perfect
match scales much better too and can be done in parallel
or 
distributed
within a routing chip.  Doing the same for longest-match 
requires a lot
more effort.  With perfect-match having 2 million routes
is 
not much of
a problem too.

-- 
Andre



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