Denic (.de) blocking 6to4 nameservers (since begin feb 2010)

Mikael Abrahamsson swmike at
Tue Feb 16 06:47:03 UTC 2010

On Tue, 16 Feb 2010, Nathan Ward wrote:

> XP won't ask for AAAA unless it has non-Teredo connectivity though I don't think.

That doesn't compute considering all the XP machines with Teredo addresses 
that asked for my AAAA only content.


"Of the users getting v6 only gif from non-tunnel-space, 58% were from 
Proxad ( I believe), and then on the list came UNINET, SUNET, FUNET 
(university networks in .no, .se and .fi) and Hurricane electric.

98% of Teredo users run Windows XP.
88% of 6to4 users run Windows Vista."

So 98% of Teredo users getting the v6only content (using DNS) was using 
WinXP, so it does seem it does AAAA lookups.

Mikael Abrahamsson    email: swmike at

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