[88698] in North American Network Operators' Group
Re: a radical proposal (Re: protocols that don't meet the need...)
daemon@ATHENA.MIT.EDU (Edward B. DREGER)
Wed Feb 15 14:32:48 2006
Date: Wed, 15 Feb 2006 19:30:36 +0000 (GMT)
From: "Edward B. DREGER" <eddy+public+spam@noc.everquick.net>
To: nanog@merit.edu
In-Reply-To: <Pine.LNX.4.64.0602151900240.3920@sheen.jakma.org>
Errors-To: owner-nanog@merit.edu
PJ> Date: Wed, 15 Feb 2006 19:02:11 +0000 (GMT)
PJ> From: Paul Jakma
PJ> > Of course not. Let SBC and Cox obtain a _joint_ ASN and _joint_ address
PJ> > space. Each provider announces the aggregate co-op space via the joint
PJ> > ASN as a downstream.
PJ>
PJ> This is unworkable obviously: Think next about SBC and (say) Verizon
No, it is not unworkable. Think through it a bit more. Although the
problem is theoretically O(N^2), in practice it is closer to O(N). Note
that _routing itself_ is theoretically an O(N^2) problem. Do we say
that it is "unworkable obviously"? No.
PJ> customers, then what about those with Cox and Verizon, then SBC/Cox/Verizon.
PJ> etc.
Yes, one ASN is required per cooperating pair. Just how many pairs do
you think there are? Now compare with the number of leaves that [would
[like to]] dual-home.
If you have 100 providers, each cooperating with every single one of the
others, that's
100 * 99 / 2 = 4950
different ASes. Noticeable, but still a long way from 4-octet ASN
territory. And guess what? Each downstream would need its own ASN
otherwise; this is just one ASN per cooperating pair.
How many transit ASes are there? And will each one share a downstream
with all of the others?
http://www.caida.org/analysis/routing/
I'll hazard a guess that a transit cooperates with, on average, no more
than five different other transits. Ergo, linear scaling.
The biggest problem is when customer's link to provider A goes down and
inbound traffic must flow through provider B. This necessitates some
sort of path between A and B where more-specifics can flow.
Eddy
--
Everquick Internet - http://www.everquick.net/
A division of Brotsman & Dreger, Inc. - http://www.brotsman.com/
Bandwidth, consulting, e-commerce, hosting, and network building
Phone: +1 785 865 5885 Lawrence and [inter]national
Phone: +1 316 794 8922 Wichita
________________________________________________________________________
DO NOT send mail to the following addresses:
davidc@brics.com -*- jfconmaapaq@intc.net -*- sam@everquick.net
Sending mail to spambait addresses is a great way to get blocked.
Ditto for broken OOO autoresponders and foolish AV software backscatter.
