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Re: implications of 6to4 for v6coex
On Sep 15, 2008, at 15:22, Brian E Carpenter wrote:
Well, I can't speak for Teredo, but 6to4 was specifically conceived
as a way of bypassing recalcitrant ISPs unwilling to offer native
IPv6 service. So deprecating it would be exactly the wrong thing:
an ISP that doesn't like 6to4 packets should be incented to provide
IPv6 service.
Transitioning to IPv6 doesn't make 6to4 and Teredo go away.
Offering IPv6-only service isn't even sufficient to relieve providers
of the requirement to deploy relays, because the return paths to
2002::/16 and 2001::/32 need to be made reliable for IPv6-only
subscribers. The requirement to provide reliable 6to4 and Teredo
relays will be with us until the happy day that the IPv4
specifications can be archived off in the Historic category. I expect
the Heat Death Of The Universe to arrive before that happens.
We need to remove the technical obstacles that service providers say
are preventing them from deploying relays for the exclusive use of
their subscribers. Otherwise, we are in serious danger of splitting
the ostensibly singular IPv6 public Internet into three separate
functional autonomies: A) the Teredo internet, B) the 6to4 internet,
and C) the native (and manually tunneled) internet. Is that what we
want?
It would be very nice if an authoritative voice at one of the very
large service providers currently resisting the deployment of relays
would step up now and explain what are those technical obstacles that
we must remove for them if IPv4-IPv6 coexistence to succeed. Perhaps,
there are no real technical obstacles at all, and I've just been led
to believe otherwise by mistake. If so, then it would be good to
understand what are the non-technical obstacles currently holding up
deployment, so we can make appropriate choices to prevent the split I
describe above.
--
james woodyatt <jhw@apple.com>
member of technical staff, communications engineering