[Mark Andrews is right, it is very difficult to separate your message from the parts you quote, my mail reader does not have a HTML parser !] On Wed, Feb 20, 2008 at 01:57:18PM +0100, Rémi Després <remi.despres@xxxxxxx> wrote a message of 44 lines which said: > The first 64 bits of IPv6 addresses are still available to > identify sites from which connections are initiated. I was not speaking about you *can* do but about what people *do* today. A lot of people use the existence (or not) of a PTR record to grant you access or not. You may tell them "PTR is useless, use the first 64 bits of the address instead", they won't listen. > PTR RRs are normally used to get names corresponding to prefixes, > not to addresses, so that there is IMU no reverse DNS problem > here. AFAIK, there is no DNS way to resolve prefixes into names (RFC 1101, may be? Can we apply it to IPv6 addresses?). A PTR is for a complete adress, not for a prefix. _______________________________________________ Ietf@xxxxxxxx http://www.ietf.org/mailman/listinfo/ietf