> The relationship is that DNS is acting as an index service > for IPv6 addresses. In doing so it treats them as simple > hierarchical addresses, i.e. like fat IPv4 addresses. > > The question as to whether that is the correct handling of > IPv6 addresses is a valid one. This thread started with > exactly such a question being raised, but the rationale on > how DNS *could* be optimized for IPV6 was not spelled out. There is no IPv6 service that guarantees that the identifiers are actually world-wide unique. In fact, there is ample evidence that they often will not be. Poorly configured interface cards are known to have phony IEEE-802 addresses; privacy addresses are random numbers that are only statistically unique; configured addresses may use user assigned values. In all these cases, local collisions can be detected, global collisions cannot be. There is also no requirement that a given multi-homed hosts combines the same identifier with different prefixes. Privacy advocates will no doubt argue that a multi-homed host should associate different identifiers with different provider prefixes, so it cannot be tracked by big-brother. -- Christian Huitema