[85610] in North American Network Operators' Group
Re: shim6 (was Re: IPv6 news)
daemon@ATHENA.MIT.EDU (Joe Abley)
Fri Oct 14 15:21:17 2005
In-Reply-To: <F8230CDF-2A05-42C4-B2D1-4D3A5667A1A9@nominum.com>
Cc: "Christopher L.Morrow" <christopher.morrow@mci.com>,
NANOG list <nanog@nanog.org>
From: Joe Abley <jabley@isc.org>
Date: Fri, 14 Oct 2005 15:19:27 -0400
To: David Conrad <david.conrad@nominum.com>
Errors-To: owner-nanog@merit.edu
On 14-Oct-2005, at 14:48, David Conrad wrote:
> On Oct 14, 2005, at 7:57 AM, Joe Abley wrote:
>
>> The big gap in the multi-homing story for v6 is for end sites,
>> since those are specifically excluded by all the RIRs' policies on
>> PI addressing right now. Shim6 is intended to be a solution for
>> end sites.
>
> Since shim6 requires changes in protocol stacks on nodes, my
> impression has been that it isn't a _site_ multihoming solution,
> but rather a _node_ multihoming solution. Is my impression incorrect?
There is no shortage of rough corners to file down, and I am behind
on my shim6 mail, but the general idea is to let end sites multi-home
in the "bag-o-PA-prefixes" style and let the nodes within that site
use their multiple globally-unique addresses (one per upstream, say)
to allow sessions to survive rehoming events.
>> Are you suggesting that something else is required for ISPs above
>> and beyond announcing PI space with BGP, or that shim6 (once baked
>> and real) would present a threat to ISPs?
>
> If my impression is correct, then my feeling is that something else
> is required. I am somewhat skeptical that shim6 will be
> implemented in any near term timeframe and it will take a very long
> time for existing v6 stacks to be upgraded to support shim6. What
> I suspect will be required is real _site_ multihoming. Something
> that will take existing v6 customer sites and allow them to be
> multi-homed without modification to each and every v6 stack within
> the site.
For end sites, that's a wildly-held opinion.
For ISPs, it's not required, since ISPs can already multi-home in the
manner you describe, using PI addresses and BGP.
Joe
