Network Working Group F. Xia Internet-Draft B. Sarikaya Expires: January 1, 2010 Huawei USA June 30, 2009 Differentiated Services Support for Proxy Mobile IPv6 draft-xia-netext-qos-00.txt 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 January 1, 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 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. Xia & Sarikaya Expires January 1, 2010 [Page 1] Internet-Draft DS support for PMIPv6 June 2009 Abstract This document describes Quality of Service (QoS) provisioning in a Proxy Mobile IPv6 domain through enabling differentiated services. When a packet is encapsulated in a mobile access gateway (or a local mobility anchor), the differentiated services codepoint (DSCP) field in the outer header is mapped to the priority of a mobile node, or the precedence of an application of the mobile node. Intermediary routers between the mobile access gateway and the local mobility anchor, which forward the packet based on the outer header of the packet, prioritize the packet according to the DSCP value of the outer header. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . 4 3. IPv4 TOS/IPv6 Traffic Class Overview . . . . . . . . . . . . . 4 4. Operations . . . . . . . . . . . . . . . . . . . . . . . . . . 5 4.1. Priority Download from AAA . . . . . . . . . . . . . . . . 5 4.2. PHP Mapping . . . . . . . . . . . . . . . . . . . . . . . . 5 4.3. Encapsulation and Forwarding . . . . . . . . . . . . . . . 5 5. Security Considerations . . . . . . . . . . . . . . . . . . . . 6 6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 6 7. References . . . . . . . . . . . . . . . . . . . . . . . . . . 6 7.1. Normative References . . . . . . . . . . . . . . . . . . . 6 7.2. Informative References . . . . . . . . . . . . . . . . . . 7 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 8 Xia & Sarikaya Expires January 1, 2010 [Page 2] Internet-Draft DS support for PMIPv6 June 2009 1. Introduction Proxy Mobile IPv6 protocol [RFC5213] specifies network-based IP mobility management support to a mobile node, without requiring the participation of the mobile node in any IP mobility related signaling. The core functional entities for proxy mobile IPv6 are the Local Mobility Anchor (LMA) and the Mobile Access Gateway (MAG). After signalling exchanges between the LMA and the MAG, a bi- directional tunnel is established. The local mobility anchor, being the topological anchor point for the mobile node's home network prefix(es), receives any packets that are sent to the mobile node by any node in or outside the Proxy Mobile IPv6 domain. The local mobility anchor forwards these received packets to the mobile access gateway through the bi-directional tunnel. The mobile access gateway on other end of the tunnel, after receiving the packet, removes the outer header and forwards the packet on the access link to the mobile node. The mobile access gateway acts as the default router on the point-to- point link shared with the mobile node. Any packet that the mobile node sends to any correspondent node will be received by the mobile access gateway and will be sent to its local mobility anchor through the bi-directional tunnel. The local mobility anchor on the other end of the tunnel, after receiving the packet, removes the outer header and routes the packet to the destination. The following is the supported packet encapsulation modes that can be used by the mobile access gateway and the local mobility anchor for tunneling mobile node's IPv6 datagrams and for supporting IPv4 transport. o IPv6-In-IPv6 - IPv6 datagram encapsulated in an IPv6 packet o IPv6-In-IPv4 - IPv6 datagram encapsulation in an IPv4 packet o IPv6-In-IPv4-UDP - IPv6 datagram encapsulation in an IPv4 UDP packet o IPv6-In-IPv4-UDP-TLV - IPv6 datagram encapsulation in an IPv4 UDP packet with a TLV header. [RFC5213] and its companion document [I-D.ietf-netlmm-pmip6-ipv4-support] details the above encapsulations. IPv6-In-IPv6 is taken as an instance in this document, IPv4 encapsulation is also applicable. [RFC5213] only describes how the ECN (Explicit Congestion Xia & Sarikaya Expires January 1, 2010 [Page 3] Internet-Draft DS support for PMIPv6 June 2009 Notification) part of IPv6 Traffic Class field being handled at the tunnel entry and exit points, and there is no special consideration on DSCP part of the field. This document describes Quality of Service (QoS) provisioning in a Proxy Mobile IPv6 domain through enabling differentiated services. When a packet is encapsulated in a mobile access gateway (or a local mobility anchor), the DSCP (differentiated services codepoint) field in the outer header is mapped to the priority of a mobile node, or the precedence of an application of the mobile node. Intermediary routers between the mobile access gateway and the local mobility anchor, which forward traffic based on outer headers of the packets, prioritize the packets according to the DSCP values of the outer headers. 2. Terminology 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]. The terminology in this document is based on the definitions in [RFC5213] 3. IPv4 TOS/IPv6 Traffic Class Overview Traffic Class field in the IPv6 header [RFC2460] and Type of Service field in the IPv4 header [RFC0791] serve the same function which is available for use by originating nodes and/or forwarding routers to identify and distinguish between different classes or priorities of IPv6/IPv4 packets. [RFC2474] and [RFC3168] further detail Traffic Class/ Type of Service field by defining DSCP and ECN field as following. 0 1 2 3 4 5 6 7 +-----+-----+-----+-----+-----+-----+-----+-----+ | DS FIELD, DSCP | ECN FIELD | +-----+-----+-----+-----+-----+-----+-----+-----+ DSCP: differentiated services codepoint ECN: Explicit Congestion Notification Regarding how to make use of DSCP field, [RFC2475] defines an architecture for implementing scalable service differentiation in the Internet. At the same time, [RFC2597] specifies a general use differentiated services Per-Hop-Behavior (PHB) Group called Assured Forwarding (AF), while [RFC2598] describes a PHB called Expedited Forwarding. Xia & Sarikaya Expires January 1, 2010 [Page 4] Internet-Draft DS support for PMIPv6 June 2009 [RFC5213] only describes how the ECN information being handled at the tunnel entry and exit points, and there is no special consideration on DSCP. 4. Operations 4.1. Priority Download from AAA The priority of subscribers MAY be stored in the mobile node's policy profile which is downloaded from an AAA server to the mobile access gateway once the mobile node attaches to a Proxy Mobile IPv6 Domain and performs access authentication. During the binding update exchange between the mobile access gateway and the local mobility anchor, the local mobility anchor MAY interact with the AAA server in order to access the mobile node's profile and update the remote policy store with the mobility session related information. 4.2. PHP Mapping To differientiate subscribers' packets forwarded between the mobile access gateway and the local mobility anchor, the priority of subscribers MUST be mapped to standard Per-Hop-Behavior. Different operators MAY have different mapping, and the following is just as an example. +--------------+-----------------------+ | Priority | PHP | |--------------|-----------------------| | Platinum | EF | | Golden | AF4 | | Silver | AF1 | | Other | BE | +--------------+-----------------------+ Further, packets MAY even be differentiated by application types, for example, VoIP service of Golden subscribers takes priority of web surfing service of Platinum subscribers. 4.3. Encapsulation and Forwarding On receiving a packet from a correspondent node with the destination address matching a mobile node's home network prefix(es), the local mobility anchor then Xia & Sarikaya Expires January 1, 2010 [Page 5] Internet-Draft DS support for PMIPv6 June 2009 o decides the priority based on the mobile node's profile and/or application type, o maps the priority to a pre-defined Per-Hop-Behavior, o and fills the DSCP field of outer IP header when forwarding the packet through the bi-directional tunnel. Intermediary routers between the mobile access gateway and the local mobility anchor, which forward traffic based on the outer header of the packet, prioritize the packet according to the DSCP value of the outer header. A similar processing as above applies when the mobile access gateway forwards upstream packets of the mobile node. 5. Security Considerations Security consideration of [RFC5213] applies, and this document does not introduce extra security threats. 6. Acknowledgements TBD. 7. References 7.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC5213] Gundavelli, S., Leung, K., Devarapalli, V., Chowdhury, K., and B. Patil, "Proxy Mobile IPv6", RFC 5213, August 2008. [RFC2474] Nichols, K., Blake, S., Baker, F., and D. Black, "Definition of the Differentiated Services Field (DS Field) in the IPv4 and IPv6 Headers", RFC 2474, December 1998. [RFC3168] Ramakrishnan, K., Floyd, S., and D. Black, "The Addition of Explicit Congestion Notification (ECN) to IP", RFC 3168, September 2001. [RFC2460] Deering, S. and R. Hinden, "Internet Protocol, Version 6 (IPv6) Specification", RFC 2460, December 1998. [RFC0791] Postel, J., "Internet Protocol", STD 5, RFC 791, Xia & Sarikaya Expires January 1, 2010 [Page 6] Internet-Draft DS support for PMIPv6 June 2009 September 1981. [RFC2475] Blake, S., Black, D., Carlson, M., Davies, E., Wang, Z., and W. Weiss, "An Architecture for Differentiated Services", RFC 2475, December 1998. [RFC2597] Heinanen, J., Baker, F., Weiss, W., and J. Wroclawski, "Assured Forwarding PHB Group", RFC 2597, June 1999. [RFC2598] Jacobson, V., Nichols, K., and K. Poduri, "An Expedited Forwarding PHB", RFC 2598, June 1999. 7.2. Informative References [I-D.ietf-netlmm-pmip6-ipv4-support] Wakikawa, R. and S. Gundavelli, "IPv4 Support for Proxy Mobile IPv6", draft-ietf-netlmm-pmip6-ipv4-support-12 (work in progress), April 2009. Xia & Sarikaya Expires January 1, 2010 [Page 7] Internet-Draft DS support for PMIPv6 June 2009 Authors' Addresses Frank Xia Huawei USA 1700 Alma Dr. Suite 500 Plano, TX 75075 Phone: +1 972-509-5599 Email: xiayangsong@huawei.com Behcet Sarikaya Huawei USA 1700 Alma Dr. Suite 500 Plano, TX 75075 Phone: +1 972-509-5599 Email: sarikaya@ieee.org Xia & Sarikaya Expires January 1, 2010 [Page 8]