Randy, On 2012-04-04 14:41, Randy Bush wrote: >> We could go on having this argument, or we could take constructive steps >> to deal with the new flexibility that we have gained from IPv6, > > uh, i hate to spoil your fantasy. but large ipv4 deployments want an > absolutely minimal, compatible, feature-match upgrade to ipv6. Yes of course. Isn't that what straight dual stack deployment is meant to provide? (I don't mean that it does provide it perfectly, but that is the goal of straight dual stack and countless people have reported that dual stack just works.) The flexibility comes after that. John, On 2012-04-04 14:34, John C Klensin wrote: > And, for better or worse, the existence and work programs of > that large number of WGs -- seemingly growing over the years and > including SOFTWIRES and others that are more specifically > focused on transition -- leads some skeptics to conclude that we > still don't understand how to transition to IPv6 What we are seeing in the last few years is a search for coexistence mechanisms for operators who are facing up to IPv4 exhaustion without having rolled out IPv6 in time. That's not a failure of the IETF; actually it's the IETF responding to operators. > or to operate > it once we get there. People who got there a while ago are operating IPv6 as a matter of course. I don't see anything happening in IPv6 rollout that didn't happen during IPv4 rollout ~20 years ago. Of course there will be a shakedown period for every operator. > "...deploy kludges in the interim" > strategy which probably does no one any good in the long term. Sad but true. Brian