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]