RFC 3596 (rfc3596) - Page 2 of 8

DNS Extensions to Support IP Version 6

RFC 3596             DNS Extensions to Support IPv6         October 2003


   6.  Intellectual Property Statement. . . . . . . . . . . . . . . .  4
   Acknowledgments. . . . . . . . . . . . . . . . . . . . . . . . . .  5
   Appendix A: Changes from RFC 1886. . . . . . . . . . . . . . . . .  6
   Normative References . . . . . . . . . . . . . . . . . . . . . . .  6
   Informative References . . . . . . . . . . . . . . . . . . . . . .  6
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . .  7
   Full Copyright Statement . . . . . . . . . . . . . . . . . . . . .  8

1. Introduction

   Current support for the storage of Internet addresses in the Domain
   Name System (DNS) [1,2] cannot easily be extended to support IPv6
   addresses [3] since applications assume that address queries return
   32-bit IPv4 addresses only.

   To support the storage of IPv6 addresses in the DNS, this document
   defines the following extensions:

      o A resource record type is defined to map a domain name to an
        IPv6 address.

      o A domain is defined to support lookups based on address.

      o Existing queries that perform additional section processing to
        locate IPv4 addresses are redefined to perform additional
        section processing on both IPv4 and IPv6 addresses.

   The changes are designed to be compatible with existing software.
   The existing support for IPv4 addresses is retained.  Transition
   issues related to the co-existence of both IPv4 and IPv6 addresses in
   the DNS are discussed in [4].

   The IP protocol version used for querying resource records is
   independent of the protocol version of the resource records; e.g.,
   IPv4 transport can be used to query IPv6 records and vice versa.

   This document combines RFC 1886 [5] and changes to RFC 1886 made by
   RFC 3152 [6], obsoleting both.  Changes mainly consist in replacing
   the IP6.INT domain by IP6.ARPA as defined in RFC 3152.

2. New resource record definition and domain

   A record type is defined to store a host's IPv6 address.  A host that
   has more than one IPv6 address must have more than one such record.







Thomson, et al.             Standards Track