On 22 Jan 2011, at 18:48, Brian E Carpenter wrote: > What nightmare? I find IPv6 dual stack works just fine. It does, when your connectivity is working. Unfortunately, the 0.1% (or whatever it is) of users whose connectivity isn't working seem to be sufficient in number to prevent large sites from deploying, and a number of others to just turn IPv6 off. Not news, except I'd hate for this to be justification in keeping dual-stack from happening (the effects of which must be considerably worse than just losing 0.1% of users), especially since the publicity about "World IPv6 Day" has brought the whole issue to light. Of course, I'd also like Google to run IPv6 (on its main web servers) for longer than 24 hours at a time. :-) > However, see draft-wing-v6ops-happy-eyeballs-ipv6 Yes. I'd love there to be some sort of consensus on it, or something like it. I'd focus more on testing connectivity, though, rather than optimal calculation of IPv6 reachability using one protocol/application to any given place at the time (i.e. rough and ready determination at OS boot whether we're on a broken network, EG). It would not be foolproof, but it would not need to be in order to be useful in the short-term. Perhaps Happy Eyeballs is the answer. Cheers, Sabahattin _______________________________________________ Ietf mailing list Ietf@xxxxxxxx https://www.ietf.org/mailman/listinfo/ietf