--- 1/draft-ietf-v6ops-464xlat-02.txt 2012-05-08 04:15:46.114671782 +0200 +++ 2/draft-ietf-v6ops-464xlat-03.txt 2012-05-08 04:15:46.142671978 +0200 @@ -1,21 +1,21 @@ Internet Engineering Task Force M. Mawatari Internet-Draft Japan Internet Exchange Co.,Ltd. Intended status: BCP M. Kawashima -Expires: October 19, 2012 NEC AccessTechnica, Ltd. +Expires: November 9, 2012 NEC AccessTechnica, Ltd. C. Byrne T-Mobile USA - April 17, 2012 + May 8, 2012 464XLAT: Combination of Stateful and Stateless Translation - draft-ietf-v6ops-464xlat-02 + draft-ietf-v6ops-464xlat-03 Abstract This document describes an architecture (464XLAT) for providing limited IPv4 connectivity across an IPv6-only network by combining existing and well-known stateful protocol translation RFC 6146 in the core and stateless protocol translation RFC 6145 at the edge. 464XLAT is a simple and scalable technique to quickly deploy limited IPv4 access service to mobile and wireline IPv6-only edge networks without encapsulation. @@ -28,21 +28,21 @@ 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 October 19, 2012. + This Internet-Draft will expire on November 9, 2012. Copyright Notice Copyright (c) 2012 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 @@ -63,26 +63,27 @@ 5.2. Wireless 3GPP Network Architecture . . . . . . . . . . . . 7 6. Applicability . . . . . . . . . . . . . . . . . . . . . . . . 7 6.1. Wireline Network Applicability . . . . . . . . . . . . . . 7 6.2. Wireless 3GPP Network Applicability . . . . . . . . . . . 8 7. Implementation Considerations . . . . . . . . . . . . . . . . 9 7.1. IPv6 Address Format . . . . . . . . . . . . . . . . . . . 9 7.2. IPv4/IPv6 Address Translation Chart . . . . . . . . . . . 9 7.3. Traffic Treatment Scenarios . . . . . . . . . . . . . . . 10 7.4. DNS Proxy Implementation . . . . . . . . . . . . . . . . . 11 7.5. IPv6 Prefix Handling . . . . . . . . . . . . . . . . . . . 11 - 7.6. CLAT in a Gateway . . . . . . . . . . . . . . . . . . . . 11 - 7.7. CLAT to CLAT communications . . . . . . . . . . . . . . . 11 + 7.6. Relationship between CLAT and NAT44 . . . . . . . . . . . 11 + 7.7. CLAT in a Gateway . . . . . . . . . . . . . . . . . . . . 11 + 7.8. CLAT to CLAT communications . . . . . . . . . . . . . . . 12 8. Deployment Considerations . . . . . . . . . . . . . . . . . . 12 9. Security Considerations . . . . . . . . . . . . . . . . . . . 12 - 10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12 - 11. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 12 + 10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13 + 11. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 13 12. References . . . . . . . . . . . . . . . . . . . . . . . . . . 13 12.1. Normative References . . . . . . . . . . . . . . . . . . . 13 12.2. Informative References . . . . . . . . . . . . . . . . . . 13 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 14 1. Introduction The IANA unallocated IPv4 address pool was exhausted on February 3, 2011. Each RIR's unallocated IPv4 address pool will exhaust in the near future. It will be difficult for many networks to assign IPv4 @@ -107,25 +108,24 @@ the future case of IPv6-only servers and peers to be reached from legacy IPv4-only hosts. The 464XLAT architecture encourages IPv6 transition by making IPv4 services reachable across IPv6-only networks and providing IPv6 and IPv4 connectivity to single-stack IPv4 or IPv6 servers and peers. Running a single-stack IPv6-only network has several operational benefits in terms of increasing scalability and decreasing operational complexity. Unfortunately, there are important cases where IPv6-only networks fail to meet subscriber expectations, as - described in [I-D.arkko-ipv6-only-experience]. The 464XLAT overcomes - the issues described in [I-D.arkko-ipv6-only-experience] to provide - subscribers the full IPv6 and limited IPv4 functionality while - providing the network operator the benefits of a simple yet highly - scalable single-stack IPv6 network. + described in [RFC6586]. The 464XLAT overcomes the issues described + in [RFC6586] to provide subscribers the full IPv6 and limited IPv4 + functionality while providing the network operator the benefits of a + simple yet highly scalable single-stack IPv6 network. 2. 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 [RFC2119]. 3. Terminology PLAT: PLAT is Provider side translator(XLAT) that complies with @@ -314,22 +314,21 @@ additional IPv6 PDP network attachments since that does not solve the near-term IPv4 scarcity issues and it increases cost in most cases. The most logical path forward is to replace IPv4 with IPv6 and replace the common NAT44 with stateful translation [RFC6146] and DNS64 [RFC6147]. Extensive live network testing with hundreds of friendly-users has shown that IPv6-only network attachments for mobile devices supports over 85% of the common applications on the Android mobile operating systems. The remaining 15% of applications do not work because the application requires an IPv4 socket or the application does an IPv4-referral. These findings are consistent - with the mobile IPv6-only user experience in - [I-D.arkko-ipv6-only-experience]. + with the mobile IPv6-only user experience in [RFC6586]. 464XLAT in combination with stateful translation [RFC6146] and DNS64 [RFC6147] allows 85% of the Android applications to continue to work with single translation or native IPv6 access. For the remaining 15% of applications that require IPv4 connectivity, the CLAT function on the UE provides a private IPv4 address and IPv4 default-route on the host for the applications to reference and bind to. Connections sourced from the IPv4 interface are immediately routed to the CLAT function and passed to the IPv6-only mobile network, destine to the PLAT. In summary, the UE has the CLAT function that does a stateless @@ -429,47 +429,56 @@ for each DNS lookup. The CLAT SHOULD set itself as the DNS server via DHCP or other means and proxy DNS queries for IPv4 and IPv6 clients. Using the CLAT enabled home router or UE as a DNS proxy is a normal consume gateway function and simplifies the traffic flow so that only IPv6 native queries are made across the access network. The CLAT SHOULD allow for a client to query any DNS server of its choice and bypass the proxy. 7.5. IPv6 Prefix Handling - There are two approaches. In one of the cases, the CLAT will have a - dedicated /64 via DHCPv6 prefix delegation [RFC3633] or other means - to source and receive IPv6 packets associated with the [RFC6145] - stateless translation of IPv4 packets to the local clients. If the - CLAT choose one /64 prefix for translation from delegated prefix, - then it SHOULD NOT be used for anything else. + From the delegated DHCPv6 [RFC3633] prefix, a /64 is dedicated to + source and receive IPv6 packets associated with the stateless + translation [RFC6145]. In another cases where the access network does not allow for a dedicated translation prefix, the CLAT will do NAT44 such that all private IPv4 sourced LAN packets appears from one private IPv4 address which is statelessly translated to one IPv6 address. The CLAT MAY discover the Pref64::/n of the PLAT via some method such as DHCPv6 option, TR-069, DNS APL RR [RFC3123] or [I-D.ietf-behave-nat64-discovery-heuristic]. -7.6. CLAT in a Gateway +7.6. Relationship between CLAT and NAT44 + + If the CLAT does not have dedicated IPv6 prefix for translation, the + CLAT does NAT44 as an internal function which never appears on the + wire. + + Incoming source IPv4 packets from the LAN of [RFC1918] addresses are + NAT44 to the CLAT host address on the LAN of one [RFC1918] address. + Then, the CLAT will do a stateless translation [RFC6145] so that the + IPv4 packets from one [RFC1918] address are translated to the CLAT + LAN IPv6 address as described in [RFC6052]. + +7.7. CLAT in a Gateway The CLAT is a stateless translation feature which can be implemented in a common home router or mobile phone that has a mobile router feature. The router with CLAT function SHOULD provide common router services such as DHCP of [RFC1918] addresses, DHCPv6, and DNS service. The router SHOULD set itself as the DNS server advertised via DHCP or other means to the clients so that it may implement the DNS proxy function to avoid double translation of DNS request. -7.7. CLAT to CLAT communications +7.8. CLAT to CLAT communications While CLAT to CLAT IPv4 communication may work when the client IPv4 subnets do not overlap, this traffic flow is out of scope. 464XLAT is a hub and spoke architecture focused on enabling IPv4-only services over IPv6-only access networks. 8. Deployment Considerations Even if the Internet access provider for consumers is different from the PLAT provider (another Internet access provider or Internet @@ -509,23 +518,23 @@ 10. IANA Considerations This document has no actions for IANA. 11. Acknowledgements The authors would like to thank JPIX NOC members, JPIX 464XLAT trial service members, Seiichi Kawamura, Dan Drown, Brian Carpenter, Rajiv Asati, Washam Fan, Behcet Sarikaya, Jan Zorz, Remi Despres, Tatsuya - Oishi, Lorenzo Colitti, Erik Kline, and Ole Troan for their helpful - comments. We also would like to thank Fred Baker and Joel Jaeggli - for their support. + Oishi, Lorenzo Colitti, Erik Kline, Ole Troan, Maoke Chen, and Gang + Chen for their helpful comments. We also would like to thank Fred + Baker and Joel Jaeggli for their support. 12. References 12.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC6052] Bao, C., Huitema, C., Bagnulo, M., Boucadair, M., and X. Li, "IPv6 Addressing of IPv4/IPv6 Translators", RFC 6052, @@ -536,25 +545,20 @@ [RFC6145] Li, X., Bao, C., and F. Baker, "IP/ICMP Translation Algorithm", RFC 6145, April 2011. [RFC6146] Bagnulo, M., Matthews, P., and I. van Beijnum, "Stateful NAT64: Network Address and Protocol Translation from IPv6 Clients to IPv4 Servers", RFC 6146, April 2011. 12.2. Informative References - [I-D.arkko-ipv6-only-experience] - Arkko, J. and A. Keranen, "Experiences from an IPv6-Only - Network", draft-arkko-ipv6-only-experience-05 (work in - progress), February 2012. - [I-D.hazeyama-widecamp-ipv6-only-experience] Hazeyama, H., Hiromi, R., Ishihara, T., and O. Nakamura, "Experiences from IPv6-Only Networks with Transition Technologies in the WIDE Camp Spring 2012", draft-hazeyama-widecamp-ipv6-only-experience-01 (work in progress), March 2012. [I-D.ietf-behave-nat64-discovery-heuristic] Savolainen, T., Korhonen, J., and D. Wing, "Discovery of IPv6 Prefix Used for IPv6 Address Synthesis", @@ -593,20 +597,23 @@ [RFC6333] Durand, A., Droms, R., Woodyatt, J., and Y. Lee, "Dual- Stack Lite Broadband Deployments Following IPv4 Exhaustion", RFC 6333, August 2011. [RFC6459] Korhonen, J., Soininen, J., Patil, B., Savolainen, T., Bajko, G., and K. Iisakkila, "IPv6 in 3rd Generation Partnership Project (3GPP) Evolved Packet System (EPS)", RFC 6459, January 2012. + [RFC6586] Arkko, J. and A. Keranen, "Experiences from an IPv6-Only + Network", RFC 6586, April 2012. + Authors' Addresses Masataka Mawatari Japan Internet Exchange Co.,Ltd. KDDI Otemachi Building 19F, 1-8-1 Otemachi, Chiyoda-ku, Tokyo 100-0004 JAPAN Phone: +81 3 3243 9579 Email: mawatari@jpix.ad.jp