IPv6 routing /48s
Jack Bates
jbates at brightok.net
Fri Nov 21 16:16:11 UTC 2008
Florian Weimer wrote:
>>> No, unfortunately broken 6to4 auto-configuration (ie, in Vista,
>>> XPSP2, when on a non-RFC1918 IP address) breaks, and you get 90s
>>> timeouts before falling back to IPv4/A.
>> This must be a broken RFC 3484 implementation:
>> - 6to4 should be less prerefed than IPv4 if the service has both AAAA
>> and A record.
>
> RFC 3848 generally prefers IPv6 over IPv4 and fails if the host
> running its algorithm has neither IPv6 connectivity nore mean to
> detect that efficiently. I think Windows does something in the second
> area.
Yes and no. The test that was being run used 6to4 addresses, so every
6to4 capable device did try to reach it via 6to4, since that is
preferred over IPv4. If it had used non-6to4 addressing, then IPv4 would
had been preferred on those hosts that didn't have non-6to4 addresses.
This is one reason why I believe using 6to4 addresses to be an issue for
content providers. If they use non-6to4 addressing for the content, then
most people will prefer IPv4 except for those who have configured
non-6to4 addresses or altered the labels to force 6to4 to work with
non-6to4 addressing.
Gads, is it appropriate to just say Native when referring to non-6to4? lol
Jack
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