6to4 routes disappeared from most of North America?

[Todd Vierling <tv () duh org>]

Maybe I missed it, but was there some concerted effort to remove or block
access to the 2002::/16 route on the v6 backbone in North America recently?
Connectivity to/from 6to4-only hosts seems sketchy at best.  Of the US hosts
I've tried, only ISC has responded at all to a 6to4 packet -- and they're
routing 2002::/16 through WIDE in Japan from what I can tell.

> From about half the US IPv6 looking glasses I've tried, the route is missing
entirely.  By contrast, I can see it everywhere, typically from multiple
upstreams, in JP (no surprise there), CH, DE, and FR that I've tried so far.

I haven't been using 6to4 for almost 6 months now, but this seems like a
really alarming step backwards as far as v6 adoptability goes in dynamic
v4-pool environments.  Yes, I'm aware of the security implications of 6to4
-- but if the RFC-suggested header address checks are properly performed at
the ingress 6to4 gateway, the burden of security falls on the 6to4 user
alone, which is (IMHO) an acceptable situation.

-- 
-- Todd Vierling <tv () duh org> <tv () pobox com> <todd () vierling name>