A number of the points you raise have already been addressed. The IPV6 Reverse resolution question has been discussed at length in DNSEXT previously. In fact, it was proposed to remove reverse resolution entirely from IPV6 for just the reason Dr. Huang notes. A 128 bit IPV6 address is 16 octets. To perform reverse resolution requires traversing 16 levels of DNS tree. Even the delegations impose significantly larger trees on the registries. It is recognized that this isn't going to be very scalable, or even possible. IPV6 proposes to use ICMP Node Identification query instead. At present, there is an IPV6 reverse tree, but it is not guarenteed it will stay. It is for transition--so that gethostbyaddr() still works on IPv6 during transition.
See for example the discussions here: http://ops.ietf.org/lists/namedroppers/namedroppers.2002/msg00931.html http://ops.ietf.org/lists/namedroppers/namedroppers.2002/msg01828.html --Dean On Sat, 28 Jun 2008, Phil Regnauld wrote: > > > 2.3 Reverse Resolution > > > > Reverse Resolution uses .IN-ADDR.ARPA domain today. In IPv6, > > .IP6.ARPA was defined by [RFC3152], and more detail information can > > be found in [RFC3596]. Because IPv6 has a huge Name Space, it is > > difficult to keep reverse RRs in today's architecture. > > Question: Why ? > > Yes, IPv6 space is immense, but for the foreseeable future, only a > very small part of it will be populated. Same goes for IP6.ARPA. > But there are no data, either by you or others, supporting the > claim that it will be more difficult to accomodate reverse > information as IP6.ARPA grows. > > Do you have some simulation, model or other data-based prediction > that can be used to illustrate this problem ? -- Av8 Internet Prepared to pay a premium for better service? www.av8.net faster, more reliable, better service 617 344 9000 _______________________________________________ DNSOP mailing list DNSOP@ietf.org https://www.ietf.org/mailman/listinfo/dnsop
