[113848] in North American Network Operators' Group
Re: IPv4 Anycast?
daemon@ATHENA.MIT.EDU (Jack Bates)
Wed Apr 22 09:01:25 2009
Date: Wed, 22 Apr 2009 08:01:16 -0500
From: Jack Bates <jbates@brightok.net>
To: Zhenkai Zhu <zhenkai@ucla.edu>
In-Reply-To: <49EEC346.1000006@ucla.edu>
Cc: nanog list <nanog@nanog.org>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
Zhenkai Zhu wrote:
> Then there is basically no inter-As anycast besides the anycast prefix
> for DNS root, since I only noticed like 8 prefixes that are announced by
> more than 3 ASes..
>
I presume you are using route-views or some such to get a larger picture
of the BGP geography? I believe that many anycasts utilize the same ASN
for their anycasted address space. I would expect that a few of them
have an ASN specifically for their anycasted space.
Given that the networks are duplicates, there's no requirement that
one part of the AS needs to receive routes from the other part of the
AS. For management and such of the devices, I presume there are separate
netblocks advertised with a different ASN (possibly even statically
assigned by a hosting network).
Jack
