Internet Engineering Task Force G. Chen Internet-Draft B. Zhou Intended status: Informational China Mobile Expires: January 7, 2010 July 6, 2009 Host-based Translation Problem Statement draft-chen-host-ipv6-ps-00 Status of this Memo This Internet-Draft is submitted to IETF in full conformance with the provisions of BCP 78 and BCP 79. 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. 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 January 7, 2010. Copyright Notice Copyright (c) 2009 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 Chen & Zhou Expires January 7, 2010 [Page 1] Internet-Draft Host-IPv6-PS July 2009 Provisions Relating to IETF Documents in effect on the date of publication of this document (http://trustee.ietf.org/license-info). Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Abstract When operators start to customize user terminals, host-based IPv6 translation will be feasible. Host-based translation should overcome single-point failure problems and support various connections between two IP families networks simultaneously. In addition, legacy IPv4 applications should not be modified. This document will discuss host-based translation applicable scenarios and corresponding issues. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Host-based translation scenarios and problems . . . . . . . . . 3 2.1. Host-based translation scenarios . . . . . . . . . . . . . 3 2.2. Problems . . . . . . . . . . . . . . . . . . . . . . . . . 4 3. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 5 4. Security Considerations . . . . . . . . . . . . . . . . . . . . 5 5. Normative References . . . . . . . . . . . . . . . . . . . . . 5 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 5 Chen & Zhou Expires January 7, 2010 [Page 2] Internet-Draft Host-IPv6-PS July 2009 1. Introduction Current network is mostly depending on IPv4. And, several sophisticated technologies have been proposed to prolong the IPv4 lifetime, such as NAPT, A+P[A+P] . Although these solutions could alleviate IPv4 depletion pressure in a short term, the transition from IPv4 to IPv6 is still a steady trend of network development. Technical solutions of IPv6 transition could be divided into three categories, namely dual-stack, tunneling and translation technology. Dual-stack hosts can communicate with both the IPv4 and IPv6 hosts, but it can not help to resolve the IPv4 address exhaustion problems. The tunneling technology can connect IPv4 networks across IPv6-only networks and IPv6 networks across IPv4-only networks, thus one IP family communication is transparent with another IP family. The translation technology can help the communications between two address families. With regard to whether deploy translator on hosts or networks, the majority solutions would like to choose the latter since modifications on a numerous hosts were treated as not easy works. However, host-based translation schemes would progress more easily in recent time, since more and more operators start to customize hosts for their subscribers. In this document, host-based translation scenarios and underlying problems have been described. 2. Host-based translation scenarios and problems 2.1. Host-based translation scenarios Figure 1 shows host-based translation scenarios. Translator modules have been deployed on H1 and H3 located in IPv6 only network. And, both conventional IPv4 applications and IPv6 applications have been installed. H2 is legacy IPv4 host located in IPv4 site. With regard to this scenario, H1 and H3 might maintain following service connections simultaneously. o case 1: H1 and H4 initiate a service call with H2 using a IPv4 application o case 2: H1 initiates a service all with the IPv6 application of H3 using a IPv4 application Chen & Zhou Expires January 7, 2010 [Page 3] Internet-Draft Host-IPv6-PS July 2009 o case 3: H3 initiates a service call with H2 using a IPv6 application o case 4: H1 initiates a service call with the IPv4 application of H3 using a IPv4 application +-----------------------------+ +--------------------+ |IPv6 site 4/6 | | IPv4 site | | +--------+ | | | | | H1 | | | | | +--------+ | | | | | | | | | 4/6 +--------+ | | | |+-------+ | Access | +--------+ |+----------+ +----+| || H3 |--| Router |-- | NAT |---|| Internet |--| H2 || |+-------+ +--------+ +--------+ |+----------+ +----+| | | | | | 4 | | +--------+ | | +--------+ | | | DNS1 | | | | DNS2 | | | +--------+ | | +--------+ | | AAAA | | A | +-----------------------------+ +--------------------+ Figure 1 2.2. Problems From individual case point-of-view, dual-stack-lite[DS-Lite] can support case 1, and BIA [RFC3338] or BIS [RFC2767] can support the case 2, and NAT64[NAT64] can support case 3. There are no solutions to perform case 4. According to the analysis, According to the analysis, existing solution can!_t satisfy the demands of maintaining above all potential communications in the 4/6 host at one time. Furthermore, following problems should be considered. o It is hard to modify numerous conventional IPv4 applications, when the hosts only have an IPv6 connection o The hosts located in IPv6 site usually do not initiate query to DNS4 server, where IPv4 peer record is stored o The hosts usually do not identify peer application type, thus translation handling can not be performed correctly Chen & Zhou Expires January 7, 2010 [Page 4] Internet-Draft Host-IPv6-PS July 2009 3. IANA Considerations This memo includes no request to IANA. 4. Security Considerations It needs to be further identified. 5. Normative References [A+P] Bush, R., "The A+P Approach to the IPv4 Address Shortage", draft-ymbk-aplusp-03 (work in progress), March 2009. [DS-Lite] Durand, A., "Dual-stack lite broadband deployments post IPv4 exhaustion", draft-ietf-softwire-dual-stack-lite-00 (work in progress), March 2009. [NAT64] Bagnulo, M., "NAT64: Network Address and Protocol Translation from IPv6 Clients to IPv4 Servers", draft-bagnulo-behave-nat64-03.txt (work in progress), March 2009. [RFC2767] Tsuchiya, K., HIGUCHI, H., and Y. Atarashi, "Dual Stack Hosts using the "Bump-In-the-Stack" Technique (BIS)", RFC 2767, February 2000. [RFC3338] Lee, S., Shin, M-K., Kim, Y-J., Nordmark, E., and A. Durand, "Dual Stack Hosts Using "Bump-in-the-API" (BIA)", RFC 3338, October 2002. Authors' Addresses Gang Chen China Mobile 53A,Xibianmennei Ave., Xuanwu District, Beijing 100053 China Email: phdgang@gmail.com Chen & Zhou Expires January 7, 2010 [Page 5] Internet-Draft Host-IPv6-PS July 2009 Bo Zhou China Mobile 53A,Xibianmennei Ave., Xuanwu District, Beijing 100053 China Email: zhouboyj@chinamobile.com Chen & Zhou Expires January 7, 2010 [Page 6]