[126109] in North American Network Operators' Group
Re: the alleged evils of NAT,
daemon@ATHENA.MIT.EDU (David Conrad)
Fri Apr 30 21:26:44 2010
From: David Conrad <drc@virtualized.org>
In-Reply-To: <4BD9A5E7.1090904@telcodata.us>
Date: Fri, 30 Apr 2010 18:26:01 -0700
To: Paul Timmins <paul@telcodata.us>
Cc: NANOG list <nanog@nanog.org>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
Paul,
On Apr 29, 2010, at 8:29 AM, Paul Timmins wrote:
> If you change ISPs, send out an RA with the new addresses, wait a bit, =
then send out an RA with lifetime 0 on the old address.
Even if this works (and I know a lot of applications that use the =
socket() API that effectively cache the address returned by DNS for the =
lifetime of the application), how does this help situations where IPv6 =
address literals are specified in configuration files, e.g., =
resolv.conf, glue for authoritative DNS servers, firewalls/filters, =
network management systems, etc.? See sections 5 and 7 of =
http://www.rfc-editor.org/internet-drafts/draft-carpenter-renum-needs-work=
-05.txt
The point here is that if there is a non-zero cost associated with =
renumbering, there will be non-zero incentive to deploy technologies =
such as NATv6 to reduce that cost. Some folks have made the argument =
that for sites large enough for the cost of renumbering to be =
significant, they should be able to justify provider independent space =
and be willing to accept the administrative and financial cost. While =
this may be the case (I have some doubts that many of the folks using PA =
space now will be all that interested in dealing with the RIR system, =
but I may be biased), it does raise concerns about routing system growth =
and forces ISPs to be willing to accept long IPv6 prefixes from end =
users (which some ISPs have already said they won't do).
Regards,
-drc
