datatracker.ietf.org
Sign in
Version 5.6.2.p5, 2014-08-04
Report a bug

Stateful NAT64: Network Address and Protocol Translation from IPv6 Clients to IPv4 Servers
RFC 6146

Internet Engineering Task Force (IETF)                        M. Bagnulo
Request for Comments: 6146                                          UC3M
Category: Standards Track                                    P. Matthews
ISSN: 2070-1721                                           Alcatel-Lucent
                                                          I. van Beijnum
                                                          IMDEA Networks
                                                              April 2011

        Stateful NAT64: Network Address and Protocol Translation
                   from IPv6 Clients to IPv4 Servers

Abstract

   This document describes stateful NAT64 translation, which allows
   IPv6-only clients to contact IPv4 servers using unicast UDP, TCP, or
   ICMP.  One or more public IPv4 addresses assigned to a NAT64
   translator are shared among several IPv6-only clients.  When stateful
   NAT64 is used in conjunction with DNS64, no changes are usually
   required in the IPv6 client or the IPv4 server.

Status of This Memo

   This is an Internet Standards Track document.

   This document is a product of the Internet Engineering Task Force
   (IETF).  It represents the consensus of the IETF community.  It has
   received public review and has been approved for publication by the
   Internet Engineering Steering Group (IESG).  Further information on
   Internet Standards is available in Section 2 of RFC 5741.

   Information about the current status of this document, any errata,
   and how to provide feedback on it may be obtained at
   http://www.rfc-editor.org/info/rfc6146.

Bagnulo, et al.              Standards Track                    [Page 1]
RFC 6146                     Stateful NAT64                   April 2011

Copyright Notice

   Copyright (c) 2011 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Bagnulo, et al.              Standards Track                    [Page 2]
RFC 6146                     Stateful NAT64                   April 2011

Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  4
     1.1.  Features of Stateful NAT64 . . . . . . . . . . . . . . . .  5
     1.2.  Overview . . . . . . . . . . . . . . . . . . . . . . . . .  6
       1.2.1.  Stateful NAT64 Solution Elements . . . . . . . . . . .  6
       1.2.2.  Stateful NAT64 Behavior Walk-Through . . . . . . . . .  8
       1.2.3.  Filtering  . . . . . . . . . . . . . . . . . . . . . . 10
   2.  Terminology  . . . . . . . . . . . . . . . . . . . . . . . . . 11
   3.  Stateful NAT64 Normative Specification . . . . . . . . . . . . 14
     3.1.  Binding Information Bases  . . . . . . . . . . . . . . . . 14
     3.2.  Session Tables . . . . . . . . . . . . . . . . . . . . . . 15
     3.3.  Packet Processing Overview . . . . . . . . . . . . . . . . 17
     3.4.  Determining the Incoming Tuple . . . . . . . . . . . . . . 18
     3.5.  Filtering and Updating Binding and Session Information . . 20
       3.5.1.  UDP Session Handling . . . . . . . . . . . . . . . . . 21
         3.5.1.1.  Rules for Allocation of IPv4 Transport
                   Addresses for UDP  . . . . . . . . . . . . . . . . 23
       3.5.2.  TCP Session Handling . . . . . . . . . . . . . . . . . 24
         3.5.2.1.  State Definition . . . . . . . . . . . . . . . . . 24
         3.5.2.2.  State Machine for TCP Processing in the NAT64  . . 25
         3.5.2.3.  Rules for Allocation of IPv4 Transport
                   Addresses for TCP  . . . . . . . . . . . . . . . . 33
       3.5.3.  ICMP Query Session Handling  . . . . . . . . . . . . . 33
       3.5.4.  Generation of the IPv6 Representations of IPv4
               Addresses  . . . . . . . . . . . . . . . . . . . . . . 36
     3.6.  Computing the Outgoing Tuple . . . . . . . . . . . . . . . 36
       3.6.1.  Computing the Outgoing 5-Tuple for TCP, UDP, and
               for ICMP Error Messages Containing a TCP or UDP
               Packets  . . . . . . . . . . . . . . . . . . . . . . . 37
       3.6.2.  Computing the Outgoing 3-Tuple for ICMP Query
               Messages and for ICMP Error Messages Containing an
               ICMP Query . . . . . . . . . . . . . . . . . . . . . . 38

[include full document text]