[41087] in North American Network Operators' Group
Re: multi-homing fixes
daemon@ATHENA.MIT.EDU (Clayton Fiske)
Wed Aug 29 14:08:41 2001
Date: Wed, 29 Aug 2001 11:08:08 -0700
From: Clayton Fiske <clay@bloomcounty.org>
To: Iljitsch van Beijnum <iljitsch@muada.com>
Cc: nanog@merit.edu
Message-ID: <20010829110808.A88137@bloomcounty.org>
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In-Reply-To: <20010829190621.K977-100000@sequoia.muada.com>; from iljitsch@muada.com on Wed, Aug 29, 2001 at 07:12:19PM +0200
Errors-To: owner-nanog-outgoing@merit.edu
On Wed, Aug 29, 2001 at 07:12:19PM +0200, Iljitsch van Beijnum wrote:
>
> Sorry for the late reply.
>
> On Fri, 24 Aug 2001, Randy Bush wrote:
>
> > the /24s of small multihomers is half the routing table (see geoff's data)
>
> This can't possibly be correct. The last figure I read was that there are
> about 70k /24s. There are about 21k AS numbers out there. This means that
> by far most of the announcements, including /24s, are the result of lack
> of CIDR. Either because ISPs have a relatively large number of PA blocks
> (address conservation) or because of lack of aggregation.
Small multihomer /24s aren't necessarily their own. I've dealt with plenty
of customers multihoming with a /24 from their other provider without
running BGP. No extra AS number, but the /24 still shows up in the global
table. Also seen customers with their own /24, but having us originate it
rather than doing BGP with them.
-c
