RFC 1886 (rfc1886) - Page 3 of 5

DNS Extensions to support IP version 6

RFC 1886                  IPv6 DNS Extensions              December 1995


2.3 AAAA query

   An AAAA query for a specified domain name in the Internet class
   returns all associated AAAA resource records in the answer section of
   a response.

   A type AAAA query does not perform additional section processing.


2.4 Textual format of AAAA records

   The textual representation of the data portion of the AAAA resource
   record used in a master database file is the textual representation
   of a IPv6 address as defined in [3].


2.5 IP6.INT Domain

   A special domain is defined to look up a record given an address. The
   intent of this domain is to provide a way of mapping an IPv6 address
   to a host name, although it may be used for other purposes as well.
   The domain is rooted at IP6.INT.

   An IPv6 address is represented as a name in the IP6.INT domain by a
   sequence of nibbles separated by dots with the suffix ".IP6.INT". The
   sequence of nibbles is encoded in reverse order, i.e. the low-order
   nibble is encoded first, followed by the next low-order nibble and so
   on. Each nibble is represented by a hexadecimal digit. For example,
   the inverse lookup domain name corresponding to the address

       4321:0:1:2:3:4:567:89ab

   would be

b.a.9.8.7.6.5.0.4.0.0.0.3.0.0.0.2.0.0.0.1.0.0.0.0.0.0.0.1.2.3.4.IP6.INT.



3. MODIFICATIONS TO EXISTING QUERY TYPES

   All existing query types that perform type A additional section
   processing, i.e. name server (NS), mail exchange (MX) and mailbox
   (MB) query types, must be redefined to perform both type A and type
   AAAA additional section processing. These new definitions mean that a
   name server must add any relevant IPv4 addresses and any relevant



Thompson & Huitema          Standards Track