-----Original Message----- From: George Bonser [mailto:gbonser@seven.com] Sent: Monday, May 16, 2011 2:10 AM To: Iljitsch van Beijnum; Owen DeLong Cc: NANOG list Subject: RE: Yahoo and IPv6
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.
That need is acknowledged and being worked, http://www.ietf.org/mail-archive/web/behave/current/msg09634.html -d