> > Because that way the IPv4 and IPv6 swarms remain disconnected in the > absence of some dual stack peers. (I.e., if the swarm is small and > you're the only IPv6 participant.) > > It would be much better if you could go from IPv6 to IPv4 through a > NAT64.
The problem is when the client is handed an explicit address rather than a host name. In that case, there needs to be some standard environment variable for "IPv64 Prefix" that applications can query. For a browser this might be something like the configured proxy. Maybe an OS such as Windows might have a registry value for this. Maybe Linux and other unix-like variations could have a sysctl for that. There should be some standard way for a native v6 host to determine the v6 to v4 prefix to use in a NAT64 environment.
