Internet DRAFT - draft-arifumi-softwire-dslite-global-addr

draft-arifumi-softwire-dslite-global-addr






Softwires Working Group                                     A. Matsumoto
Internet-Draft                                               T. Fujisaki
Intended status: Standards Track                                     NTT
Expires: September 3, 2010                                 March 2, 2010


          Global IPv4 Address Configuration Option for DS-Lite
            draft-arifumi-softwire-dslite-global-addr-00.txt

Abstract

   When an ISP tries to deploy IPv6 and take an action for IPv4 address
   depletion, DS-Lite is reasonable approach for solving both of the
   problems.  However, it is troublesome for an ISP to have the existing
   IPv4 service facilities and DS-Lite facilities at the same time for
   not a short period of time.  This document proposes a mechanism to
   assign an IPv4 global address in DS-Lite framework, which makes every
   customer to move to DS-Lite based network, and enables an ISP to
   maintain single facility of the service network.

Status of this Memo

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

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF), its areas, and its working groups.  Note that
   other groups may also distribute working documents as Internet-
   Drafts.

   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."

   The list of current Internet-Drafts can be accessed at
   http://www.ietf.org/ietf/1id-abstracts.txt.

   The list of Internet-Draft Shadow Directories can be accessed at
   http://www.ietf.org/shadow.html.

   This Internet-Draft will expire on September 3, 2010.

Copyright Notice

   Copyright (c) 2010 IETF Trust and the persons identified as the
   document authors.  All rights reserved.




Matsumoto & Fujisaki    Expires September 3, 2010               [Page 1]

Internet-Draft        DS-Lite Global Address Option           March 2010


   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 BSD License.

   This document may contain material from IETF Documents or IETF
   Contributions published or made publicly available before November
   10, 2008.  The person(s) controlling the copyright in some of this
   material may not have granted the IETF Trust the right to allow
   modifications of such material outside the IETF Standards Process.
   Without obtaining an adequate license from the person(s) controlling
   the copyright in such materials, this document may not be modified
   outside the IETF Standards Process, and derivative works of it may
   not be created outside the IETF Standards Process, except to format
   it for publication as an RFC or to translate it into languages other
   than English.






























Matsumoto & Fujisaki    Expires September 3, 2010               [Page 2]

Internet-Draft        DS-Lite Global Address Option           March 2010


Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . . . 4
   2.  Global IPv4 Address Assignment for B4 . . . . . . . . . . . . . 4
   3.  DS-Lite Global IPv4 Address Option for DHCPv4 . . . . . . . . . 5
   4.  IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 5
   5.  Security Considerations . . . . . . . . . . . . . . . . . . . . 5
   6.  Normative References  . . . . . . . . . . . . . . . . . . . . . 5
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . . . 6










































Matsumoto & Fujisaki    Expires September 3, 2010               [Page 3]

Internet-Draft        DS-Lite Global Address Option           March 2010


1.  Introduction

   When an ISP tries to deploy IPv6 and take an action for IPv4 address
   depletion, DS-Lite [I-D.ietf-softwire-dual-stack-lite] is reasonable
   approach for solving both of the problems.

   In the existing IPv4 service, an ISP usually provides an IPv4 global
   address for each customer.  IPv4 address depletion does not mean that
   ISP will lose already acquired IPv4 global address blocks, so they
   will continue to provide the IPv4 global address service to a part of
   the existing customers regardless of whether IPv6 connectivity
   service is provided to the customers or not.

   However, it will be troublesome for an ISP to have and maintain the
   existing IPv4 service facilities and DS-Lite facilities at the same
   time and for not a short period of time.

   This document proposes a mechanism to assign an IPv4 global address
   in DS-Lite framework, which makes every customer to move to DS-Lite
   based network, and enables an ISP to maintain single facility of the
   service network.


2.  Global IPv4 Address Assignment for B4

   A new DHCPv4 option is proposed here to assign an IPv4 global address
   for a customer.  This option is used in combination with the option
   to notify DS-Lite tunnel endpoint address defined in this draft
   [I-D.ietf-softwire-ds-lite-tunnel-option].

   When a DS-Lite capable router receives both of these options, that
   means the router should behave in DS-Lite with IPv4 global address
   manner.  When it receives just a tunnel endpoint option, that means
   the router should behave in normal DS-Lite manner.

   B4 should use the received IPv4 global address as the inner address
   of its DS-Lite tunnel interface.

   AFTR has to have IPv4 routing information, which is which DS-Lite
   tunnel should be used for forwarding IPv4 packet, for each IPv4 gobal
   address assigned customer.  AFTR just acts as a router and tunnel
   endpoint, not as a NAT device for this type of customers.  In order
   to tell whether do NATing or not, AFTR should have a list of IPv4
   global address blocks for NATing, or non-NATing, or both.  And, AFTR
   has to look at the list, when it receives a packet from tunnel
   interface and also from up-stream interface.





Matsumoto & Fujisaki    Expires September 3, 2010               [Page 4]

Internet-Draft        DS-Lite Global Address Option           March 2010


3.  DS-Lite Global IPv4 Address Option for DHCPv4

   The DS-Lite Global IPv4 Address Option MUST NOT appear more than once
   in a message.

   The format of the DS-Lite Global IPv4 Address Option is shown in the
   following figure:


        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |  option-code  |  option-len   |          IPv4 address         |
       +-------------------------------+-------------------------------+
       |      IPv4 address (cont.)     |
       +-------------------------------+

                 DS-Lite Global IPv4 Address DHCPv4 Option format.



4.  IANA Considerations

   IANA is requested to allocate two DHCPv4 Option code referencing this
   document.


5.  Security Considerations

   TBD


6.  Normative References

   [I-D.ietf-softwire-ds-lite-tunnel-option]
              Hankins, D. and T. Mrugalski, "Dynamic Host Configuration
              Protocol for IPv6 (DHCPv6) Options for Dual- Stack Lite",
              draft-ietf-softwire-ds-lite-tunnel-option-01 (work in
              progress), January 2010.

   [I-D.ietf-softwire-dual-stack-lite]
              Durand, A., Droms, R., Haberman, B., Woodyatt, J., Lee,
              Y., and R. Bush, "Dual-stack lite broadband deployments
              post IPv4 exhaustion",
              draft-ietf-softwire-dual-stack-lite-03 (work in progress),
              February 2010.





Matsumoto & Fujisaki    Expires September 3, 2010               [Page 5]

Internet-Draft        DS-Lite Global Address Option           March 2010


Authors' Addresses

   Arifumi Matsumoto
   NTT PF Lab
   Midori-Cho 3-9-11
   Musashino-shi, Tokyo  180-8585
   Japan

   Phone: +81 422 59 3334
   Email: arifumi@nttv6.net


   Tomohiro Fujisaki
   NTT PF Lab
   Midori-Cho 3-9-11
   Musashino-shi, Tokyo  180-8585
   Japan

   Phone: +81 422 59 7351
   Email: fujisaki@syce.net































Matsumoto & Fujisaki    Expires September 3, 2010               [Page 6]