[133426] in North American Network Operators' Group
Re: Start accepting longer prefixes as IPv4 depletes?
daemon@ATHENA.MIT.EDU (Jack Bates)
Thu Dec 9 10:22:17 2010
Date: Thu, 09 Dec 2010 09:21:23 -0600
From: Jack Bates <jbates@brightok.net>
To: Owen DeLong <owen@delong.com>
In-Reply-To: <9E7683D3-FC88-4135-83BA-4A17A1EDC9A3@delong.com>
Cc: NANOG list <nanog@nanog.org>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
On 12/8/2010 5:07 PM, Owen DeLong wrote:
> This assumes a 1:1 ratio between prefixes and routing policies. This is unrealistic in all but the most
> trivial of networks.
>
Yet we can achieve much closer to this with IPv6 due to looser
allocation policies.
> Yes... It should. However, even with the reduced IPv6 routing table, there will be circumstances
> where multiple prefixes can efficiently be coalesced into common routing policies. Unfortunately,
> the current designs of IPv4 and IPv6 do not allow us to actually do so. What I am proposing
> would.
I agree it would be good, and every new person to BGP always asks why we
don't route packets by the AS (seems like common sense). However, I
think we'll have to wait and see on how well v6 manages with the new
allocation policies and if the routing table for it drops to a
reasonable level. This would be more acceptable than trying to shim on
the v6 protocol. The problem is, once a protocol is standardized and
implemented by the masses, changing is very difficult. It's going to be
a bumpy road as we complete v6 transition, and I doubt anyone is looking
forward to another change of that magnitude.
Jack
