[Docs] [txt|pdf] [Tracker] [Email] [Diff1] [Diff2] [Nits]

Versions: 00 01 02 03 04 05 06

Network Working Group                                       N. Matsuhira
Internet-Draft                                           Fujitsu Limited
Intended status: Informational                                 K. Horiba
Expires: February 26, 2016                                       Y. Ueno
                                                             O. Nakamura
                                                              Keio Univ.
                                                         August 25, 2015


                        SA46T Address Translator
                      draft-matsuhira-sa46t-at-06

Abstract

   This document specifies SA46T Address Translator (SA46T-AT)
   specification.  SA46T-AT enable access to IPv4 only host from IPv6
   host.  IPv4 host is identified as SA46T global address in IPv6
   address space.  The address assigned to IPv4 host may be global IPv4
   address or private IPv4 address.  SA46T-AT does not support access to
   IPv6 host from IPv4 only host.

Requirements Language

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC 2119 [RFC2119].

Status of this Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at http://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on February 26, 2016.

Copyright Notice

   Copyright (c) 2015 IETF Trust and the persons identified as the
   document authors.  All rights reserved.



Matsuhira, et al.       Expires February 26, 2016               [Page 1]


Internet-Draft                  SA46T-AT                     August 2015


   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.


Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . . . 3
   2.  SA46T-AT Architecture . . . . . . . . . . . . . . . . . . . . . 3
     2.1.  SA46T address . . . . . . . . . . . . . . . . . . . . . . . 3
     2.2.  Mapping IPv4 address and IPv6 address . . . . . . . . . . . 4
     2.3.  AddressTranslation Table  . . . . . . . . . . . . . . . . . 4
     2.4.  DNS mapping of IPv4 only host . . . . . . . . . . . . . . . 4
   3.  Sample Configuration  . . . . . . . . . . . . . . . . . . . . . 4
     3.1.  SA46T address and IPv4 network plane ID . . . . . . . . . . 4
     3.2.  Network Configuration . . . . . . . . . . . . . . . . . . . 5
     3.3.  Routing . . . . . . . . . . . . . . . . . . . . . . . . . . 6
   4.  Processing of SA46T-AT  . . . . . . . . . . . . . . . . . . . . 6
     4.1.  Configuration of SA46T-AT . . . . . . . . . . . . . . . . . 6
     4.2.  Processing from IPv6 to IPv4  . . . . . . . . . . . . . . . 7
     4.3.  Processing from IPv6 to IPv4  . . . . . . . . . . . . . . . 7
     4.4.  Other processing  . . . . . . . . . . . . . . . . . . . . . 7
   5.  IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 8
   6.  Security Considerations . . . . . . . . . . . . . . . . . . . . 8
   7.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . . . 8
   8.  References  . . . . . . . . . . . . . . . . . . . . . . . . . . 8
     8.1.  Normative References  . . . . . . . . . . . . . . . . . . . 8
     8.2.  Informative References  . . . . . . . . . . . . . . . . . . 8
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . . . 9
















Matsuhira, et al.       Expires February 26, 2016               [Page 2]


Internet-Draft                  SA46T-AT                     August 2015


1.  Introduction

   The IPv4 address exhaution already became the real.

   In 03-Feb-2011, IANA Unallocated Address Pool was exhausted.  And in
   19-Apr-2011, APNIC unallocated address pool was exhaused.  Other
   RIRs, unallocated address pool does not exhaused now, however, it
   should be a matter of time.  For more details, please refer to IPv4
   address report , http://www.potaroo.net/tools/ipv4/.

   After IPv4 address running out, IPv6 only network service should be
   provided.  SA46T [I-D.matsuhira-sa46t-spec] provide IPv4 network
   service over IPv6 only network environments.  And SA46T grobal
   address [I-D.matsuhira-sa46t-gaddr]is proposed for The Internet
   scale.

   On the other side, to maintain the continuance of service by the
   server, shifting to IPv6 is also needed.  However, there should be a
   service which has difficulty to quick shift to the IPv6.  That mean
   IPv4 service continuance is still important.

   There are two approaches which use IPv4 address effectively.  One is
   address sharing approach such as Address plus port (A+P) Approach
   [RFC6346], and the other is address re-use approach such as IPv4
   private address [RFC1918].

   SA46T-AS [I-D.matsuhira-sa46t-as] is also address sharing approch.
   SA46T-AT is equivalent to address reuse approach.


2.  SA46T-AT Architecture

2.1.  SA46T address

   Figure 1 show SA46T address[I-D.matsuhira-sa46t-spec].  SA46T global
   address is same format with SA46T address, and "SA46T address prefix"
   part should allocate for this usage.  And "IPv4 network plane ID"
   value MUST unique.


    |  96 - m bits          |          m bits          |     32 bits  |
    +-----------------------+--------------------------+--------------+
    | SA46T address prefix  |  IPv4 network plane ID   | IPv4 address |
    +-----------------------+--------------------------+--------------+


                                 Figure 1




Matsuhira, et al.       Expires February 26, 2016               [Page 3]


Internet-Draft                  SA46T-AT                     August 2015


2.2.  Mapping IPv4 address and IPv6 address

   SA46T address contain IPv4 address.  Mapping IPv4 host address to
   IPv6 address space is already done with SA46T address.  Address
   translation for IPv4 address is same as resolving SA46T address.

   IPv6 host address and corresponding IPv4 address should manage.

2.3.  AddressTranslation Table

   Figure 2 shows translation table for SA46T-AT.  Translation table
   contain three value, IPv6 adddress ot IPv6 host, mapped IPv4 address
   for the IPv6 host, and extry expire timer for remove the entry.


    +----------------------+----------------------+--------------------+
    | Address of IPv6 host | mapped IPv4 address  | entry expire timer |
    |                      | for IPv6 host        |                    |
    +----------------------+----------------------+--------------------+
    |         :            |          :           |         :          |
    ~         :            ~          :           ~         :          ~
    |         :            |          :           |         :          |
    +----------------------+----------------------+--------------------+
    | Address of IPv6 host | mapped IPv4 address  | entry expire timer |
    |                      | for IPv6 host        |                    |
    +----------------------+----------------------+--------------------+


                                 Figure 2

2.4.  DNS mapping of IPv4 only host

   In the Domain Name System, hostnames are mapped to IPv6 addresses by
   AAAA resource records.  SA46T address can be mapped to IPv4 only host
   name.


3.  Sample Configuration

3.1.  SA46T address and IPv4 network plane ID

   In this example, SA46T address prefix length is 64bits, and IPv4
   network plane ID length is 32 bits.  SA46T prefix value is 2001:0DB8:
   0:46, and IPv4 network plane ID value is 0:46.  Figure 3 shows these
   value.






Matsuhira, et al.       Expires February 26, 2016               [Page 4]


Internet-Draft                  SA46T-AT                     August 2015


    |     64  bits          |          32 bits         |     32 bits  |
    +-----------------------+--------------------------+--------------+
    | SA46T address prefix  |  IPv4 network plane ID   | IPv4 address |
    | (2001:0DB8:0:46)      | (0:46)                   |              |
    +-----------------------+--------------------------+--------------+

                                 Figure 3

3.2.  Network Configuration

   Figure 4 shows sample network configuration.  IPv6 network have 2001:
   0DB8:1:0/64 network prefix and IPv4 network have 10.0.0.0/24 network
   prefix.


     +----------------+
     |  IPv6 host     |
     |          2001:0DB8:1.0::10
     +----------------+
            |
            | 2001:0DB8:1:0/64
            |
     +----------------+
     |      2001:0DB8:1:0::1
     |                |
     |    SA46T-AT    |
     |           address pool for IPv6 host mapping
     |              192.168.0.0/24
     |                |
     |           10.0.0.1
     +----------------+
            |
            | 10.0.0.0/24
            |
     +----------------+
     | IPv4 only host |
     |                |
     |     ipv4onlyhost10.example.com
     |     10.0.0.10  |
     |     (2001:0DB8:0:46:0:64:10.0.0.10)
     |                |
     +----------------+




                                 Figure 4




Matsuhira, et al.       Expires February 26, 2016               [Page 5]


Internet-Draft                  SA46T-AT                     August 2015


   IPv6 host address is 2001:0DB8:1:0::10.  IPv4 only host address is
   10.0.0.10.  SA46T address for IPv4 only host is 2001:0DB8:0:46:0:64:
   10.0.0.10.  FQDN of IPv4 only host is ipv6onlyhost10.example.com.
   Figure 5 shows DNS entry in IPv4 address space, and Figure 6 shows
   DNS entry in IPv6 space.


   ipv6onlyhost10.example.com IN A 10.0.0.10


                                 Figure 5


   ipv6onlyhost10.example.com IN AAAA 2001:0DB8:0:46:0:64:10.0.0.10


                                 Figure 6

   The address of IPv4 interface of SA46T-AT is 10.0.0.1, and the
   address of IPv6 interface of SA46T-AT is 2001:0DB8:1:0::1.  SA46T-AT
   have also IPv4 address pool for IPv6 host mapping.  This example, the
   IPv4 address pool is 192.168.0.0/24.

   The default router for IPv4 only host is SA46T-AT's IPv4 interface
   address, 10.0.0.1.

3.3.  Routing

   SA46T-AT advertise SA46T address prefix for IPv4 only host, 2001:
   0DB8:0:46:0:64:10.0.0.0/120.  This manner is same as SA46T.


4.  Processing of SA46T-AT

4.1.  Configuration of SA46T-AT

   1.  SA46T address prefix for route advertisement (2001:0DB8:0:46:0:
       64:10.0.0.0/120)

   2.  IPv4 address pool for IPv6 hosts

   3.  entry expire default time (TBD)

   SA46T address contain IPv4 network plane ID, so SA46T-AT know IPv4
   network plane ID from SA46T address prefix.






Matsuhira, et al.       Expires February 26, 2016               [Page 6]


Internet-Draft                  SA46T-AT                     August 2015


4.2.  Processing from IPv6 to IPv4

   1.  SA46T-AT examine the exists of the entry for IPv6 host, that is
       source IPv6 address of IPv6 packet.

   2.  If there is no entry, get IPv4 address for mapping of IPv6 host
       from IPv4 address pool, and make entry to the translation table.

   3.  IF there is the entry, resove mapped IPv4 address for IPv6 host.

   4.  Make IPv4 header, source address is mapped IPv4 address, and
       destination address is from SA46T address.

   5.  Translate IPv6 packet to IPv4 packet, and send it, and reset
       entry expire timer.

   The example addess translation table is shown in Figure 7.  In this
   example, IPv6 host address is mapped to 192.168.0.200.


    +----------------------+----------------------+--------------------+
    | Address of IPv6 host | mapped IPv4 address  | entry expire timer |
    |                      | for IPv6 host        |                    |
    +----------------------+----------------------+--------------------+
    | 2001:0DB8:1.0::10    | 192.168.0.200        | TBD                |
    +----------------------+----------------------+--------------------+




                                 Figure 7

4.3.  Processing from IPv6 to IPv4

   1.  Search address translation table with key destination IPv4
       address, and resolve corrensponding IPv6 address.

   2.  Resolve source IPv6 address from sourve IPv4 address with SA46T
       address generation rule.

   3.  Translate IPv4 packet to IPv6 packet, and sent it, and reset
       extry expire timer.

4.4.  Other processing

   1.  Remove the entry of address translation table if expire.





Matsuhira, et al.       Expires February 26, 2016               [Page 7]


Internet-Draft                  SA46T-AT                     August 2015


5.  IANA Considerations

   This document may requests IANA to assign IPv6 prefix for SA46T
   Global address.


6.  Security Considerations

   Security consideration does not discussed in this memo, at this time.


7.  Acknowledgements


8.  References

8.1.  Normative References

   [I-D.matsuhira-sa46t-as]
              Matsuhira, N., "Stateless Automatic IPv4 over IPv6
              Tunneling with IPv4 Address Sharing",
              draft-matsuhira-sa46t-as-05 (work in progress), July 2013.

   [I-D.matsuhira-sa46t-gaddr]
              Matsuhira, N., "Stateless Automatic IPv4 over IPv6
              Encapsulation / Decapsulation Technology: Global SA46T
              Address Format", draft-matsuhira-sa46t-gaddr-07 (work in
              progress), July 2013.

   [I-D.matsuhira-sa46t-spec]
              Matsuhira, N., "Stateless Automatic IPv4 over IPv6
              Encapsulation / Decapsulation Technology: Specification",
              draft-matsuhira-sa46t-spec-07 (work in progress),
              July 2013.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997.

8.2.  Informative References

   [RFC1918]  Rekhter, Y., Moskowitz, R., Karrenberg, D., Groot, G., and
              E. Lear, "Address Allocation for Private Internets",
              BCP 5, RFC 1918, February 1996.

   [RFC3849]  Huston, G., Lord, A., and P. Smith, "IPv6 Address Prefix
              Reserved for Documentation", RFC 3849, July 2004.

   [RFC6346]  Bush, R., "The Address plus Port (A+P) Approach to the



Matsuhira, et al.       Expires February 26, 2016               [Page 8]


Internet-Draft                  SA46T-AT                     August 2015


              IPv4 Address Shortage", RFC 6346, August 2011.


Authors' Addresses

   Naoki Matsuhira
   Fujitsu Limited
   1-1, Kamikodanaka 4-chome, Nakahara-ku
   Kawasaki,   211-8588
   Japan

   Phone: +81-44-754-3466
   Fax:
   Email: matsuhira@jp.fujitsu.com


   Katsuhiro Horiba
   Keio Univ.
   5322 Endo
   Fujisawa,   252-8520
   Japan

   Phone:
   Fax:
   Email: qoo@sfc.wide.ad.jp
   URI:


   Yukito Ueno
   Keio Univ.
   5322 Endo
   Fujisawa,   252-8520
   Japan

   Phone:
   Fax:
   Email: eden@sfc.wide.ad.jp
   URI:













Matsuhira, et al.       Expires February 26, 2016               [Page 9]


Internet-Draft                  SA46T-AT                     August 2015


   Osamu Nakamura
   Keio Univ.
   5322 Endo
   Fujisawa,   252-8520
   Japan

   Phone:
   Fax:
   Email: osamu@wide.ad.jp
   URI:









































Matsuhira, et al.       Expires February 26, 2016              [Page 10]


Html markup produced by rfcmarkup 1.127, available from https://tools.ietf.org/tools/rfcmarkup/