IPv6 Administration Guide

DNS Extensions for IPv6

A new resource record that is defined as an AAAA record has been specified by RFC 1886. This AAAA record maps a host name into an 128–bit IPv6 address. The PTR record is still used with IPv6 to map IP addresses into host names. The thirty two 4–bit nibbles of the 128–bit address are reversed for an IPv6 address. Each nibble is converted to its corresponding hexadecimal ASCII value. Then, ip6.int is appended.