[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
RE: getaddrinfo address ordering [Re: IPv6 transition architecturediscussion]
On Wed, 27 Nov 2002, Christian Huitema wrote:
> > > It will currently always fall back to v4 if one wrote it correctly:
> > > - tries AAAA (if dns returned it)
> > > - tries A (if dns returned it)
> >
> > Sure.. but in this case www.google.com will not have AAAA records in,
> > well, about 5-10 years. They have no incentive to do so, _at all_ --
> > quite the contrary -- as their v4-enabled users would get worse
> service.
>
> A nice point of 6to4 as a transition strategy is that its performance
> are guaranteed to be very close from those of the underlying IPv4. A
> normal evolution for sites like Google would be to multihome and expose
> both a native IPv6 connection and a 6to4 connection. Address selection
> rules will guarantee that "transition" users pick the 6to4 destination,
> while native users pick the native address. This will largely deal with
> your performance concern.
This would help only if all v6 users, v6-native included, would enable
6to4 as an "optimization technique", as proposed previously.
Doesn't seem like a scalable solution.
(why v6-native? v6 native connection, here meaning non-6to4 global
addresses, cannot be guaranteed to reach google in an optimal fashion --
quite far from it.)
Another transition strategy would be to _not_ use any native v6 _at all_
yet, only 6to4 -- or feed the hosts only native more specific routes to
those networks that are "well-connected" (where you wouldn't use 6to4).
Reminds too much of Jim Flemings ideas, too scary to even contemplate.
--
Pekka Savola "Tell me of difficulties surmounted,
Netcore Oy not those you stumble over and fall"
Systems. Networks. Security. -- Robert Jordan: A Crown of Swords