Question for the WG:
Do we care about coexistance of old style and new style NAT-PT?
The new style that Brian and I are working on is going to require
changes on the IPv6 side, which won't be made over night: looking
up A records by the hosts themselves rather than having a DNS ALG
generate synthetic AAAA records for IPv4-only destinations.
The problem is that you would have to provision different DNS
resolvers for hosts that are IPv6-only and do not support the new
style NAT-PT versus the ones that do and dual stack hosts. This
could be a problem. Solution: have hosts that do DNS lookups over
IPv6 transport indicate that they support new style NAT-PT and
don't need the synthetic AAAA records through EDNS0.
Is this something we want or can we assume that old style NAT-PT is
dead so we don't have to consider issues relating to it?