MULTIMOB Group H. Deng Internet-Draft China Mobile Intended status: Informational T. Schmidt Expires: March 20, 2009 HAW Hamburg P. Seite France Telecom P. Yang Hitachi September 16, 2008 Multicast Support Requirements for Proxy Mobile IPv6 draft-deng-multimob-pmip6-requirement-00 Status of this Memo By submitting this Internet-Draft, each author represents that any applicable patent or other IPR claims of which he or she is aware have been or will be disclosed, and any of which he or she becomes aware will be disclosed, in accordance with Section 6 of 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 March 20, 2009. Deng, et al. Expires March 20, 2009 [Page 1] Internet-Draft Multicast Requirements for PMIPv6 September 2008 Abstract This document summarizes requirements for multicast listener support in Proxy Mobile IPv6 (PMIPv6) scenarios. In correspondance to PMIPv6, multicast mobility management requirements do not request any active participation of the mobile node. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Scenarios of Multicast Support for PMIPv6 . . . . . . . . . . 4 3. Requirements for multicast support in PMIPv6 . . . . . . . . . 6 3.1. Basic functional requirements . . . . . . . . . . . . . . 6 3.2. Multicast performance requirements . . . . . . . . . . . . 6 4. Architecture requirements . . . . . . . . . . . . . . . . . . 8 4.1. LMA Requirements for multicast support in PMIPv6 . . . . . 8 4.2. MAG Requirements for multicast support in PMIPv6 . . . . . 8 5. Security Considerations . . . . . . . . . . . . . . . . . . . 9 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10 7. Contributors . . . . . . . . . . . . . . . . . . . . . . . . . 11 8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 12 8.1. Normative References . . . . . . . . . . . . . . . . . . . 12 8.2. Informative References . . . . . . . . . . . . . . . . . . 12 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 13 Intellectual Property and Copyright Statements . . . . . . . . . . 14 Deng, et al. Expires March 20, 2009 [Page 2] Internet-Draft Multicast Requirements for PMIPv6 September 2008 1. Introduction Many of the current mobile network architectures as well as link layer technologies provide an independent multicast/broadcast support for dedicated group communication services, e.g., based on specific wireless channels. Typically, applications like Internet IPTV, that require voluminous content streams to be distributed to potentially large numbers of receivers, may take benefit of this transport mode. At the same time, with the development of mobile Internet protocols, the need emerged for a seamlessly available multicast solution that makes efficient use of the multipoint transmission technologies deployed by operators [MMCASTv6-PS]. As an example, mobile IPTV channels, which combine Audio/Video programs with interactive data for supplementary information (using bi-directional wireless broadband links), and with potential large audience, may take particular advantage of any multicast/ broadcast mobile support at access networks for downlink distribution of A/V streams. Among IP mobility management protocols, Proxy Mobile IPv6 (PMIPv6) [RFC5213] has been designed to bring IP mobility making the mobile nodes unaware of network layer changes. Functional entities in the PMIPv6 infrastructure are the Local Mobility Anchor (LMA) and the Mobile Access Gateway (MAG). The local mobility anchor is responsible for maintaining the mobile node's reachability state and is the topological anchor point for the mobile node's home network prefix(es). The mobile access gateway performs mobility management operations on behalf of the mobile node. Basically, the mobile access gateway is responsible for detecting the mobile node's movements, to and from the access link, and for initiating binding registrations (i.e. location updates) to the mobile node's local mobility anchor. The current PMIPv6 specification lacks dedicated support of group communication. To facilitate design of a multicast support in future solutions, this document gathers requirements for multicast listener support. In correspondance to PMIPv6, multicast mobility management requirements should not request any active participation of the mobile multicast recipient. Deng, et al. Expires March 20, 2009 [Page 3] Internet-Draft Multicast Requirements for PMIPv6 September 2008 2. Scenarios of Multicast Support for PMIPv6 According to [RFC5213], two basic routing scenarios exist in PMIPv6: the tunneling mode and local routing. The tunneling mode as displayed in Figure 1 uses IPv6-in-IPv6 encapsulation [RFC2473] (IPv6-in-IPv4 in [PMIPv6v4]) to transfer data between LMA and MAG. Thus two entities are facing an avalanche problem (cf. [MMCASTv6-PS]), the LMA in feeding multicast streams to the MAGs, and the MAG in distributing multicast on air to the mobile nodes. +-------------+ | Content | | Source | +-------------+ | *** *** *** *** * ** ** ** * * * * Fixed Internet * * * * ** ** ** * *** *** *** *** / \ +----+ +----+ |LMA1| |LMA2| +----+ +----+ LMAA1 | | LMAA2 | | \\ //\\ \\ // \\ \\ // \\ Unicast Tunnels --> \\ // \\ \\ // \\ \\ // \\ Proxy-CoA1 || || Proxy-CoA2 +----+ +----+ |MAG1| |MAG2| +----+ +----+ | | | | | | MN1 MN2 MN3 Figure 1: Multicast Scenario in PMIPv6 Tunneling Mode The local routing option has been designed to support direct node to node communication within a PMIPv6 domain. Assuming a locally available content source, the local routing mode may give rise to the scenario visualized in Figure 2. Local routing will resolve tunnel Deng, et al. Expires March 20, 2009 [Page 4] Internet-Draft Multicast Requirements for PMIPv6 September 2008 convergence issues at the LMA but not the avalanche problem point to the MAG. +----+ +----+ |LMA1| |LMA2| +----+ +----+ LMAA1 | | LMAA2 | | *** *** *** *** * ** ** ** * * * +-------------+ * Local Routing * _____ | Content | * * | Source | * ** ** ** * +-------------+ *** *** *** *** Proxy-CoA1 || || Proxy-CoA2 +----+ +----+ |MAG1| |MAG2| +----+ +----+ | | | | | | MN1 MN2 MN3 Figure 2: Multicast Scenario for PMIPv6 Local Routing PMIP multicast support must clearly address above issues but should also bring good user experience of multicast mobility. In addition, it is expected that the solution shall inherit from the basics of PMIP scenarios; in particular mobility management should not require to add specific functions to the IPv6 node. In these perspectives, following sections summarize protocol and architecture requirements for multicast support in Proxy Mobile IPv6. Deng, et al. Expires March 20, 2009 [Page 5] Internet-Draft Multicast Requirements for PMIPv6 September 2008 3. Requirements for multicast support in PMIPv6 This section summarizes the requirements for mobile multicast protocol extensions of PMIPv6. 3.1. Basic functional requirements R1 - PMIPv6 multicast mobility management MUST transparently support the reception of Any Source Multicast (ASM) and Source Specific Multicast (SSM) channels. R2 - The mobile node is responsible for initially subscribing to the multicast group(s). R3 - The mobile node MAY remain agnostic of the multicast mobility management when roaming. In particular, the node MUST not be required to re-subscribe to multicast group(s) after handoff. R4 - Multicast packet distribution within a PMIPv6 domain MUST not cause MTU-size conflicts on the network layer. In particular, path MTU discovery MUST NOT be required for multicast transmission. R5 - PMIPv6 multicast mobility management MUST comply with multicast scoping rules and restrictions. R6 - PMIPv6 multicast mobility management MUST equally cover IPv6/ IPv4 only and dual stack nodes. R7 - A multicast solution SHALL be compatible with the existing PMIPv6 network architecture and protocol structure such as multihoming and vertical handover. 3.2. Multicast performance requirements R8 - PMIPv6 transmission SHOULD realize native multicast forwarding, and where applicable conserve network resources and utilize link layer multipoint distribution to avoid data redundancy. R9 - The solution SHALL minimize multicast forwarding delays to provide seamless and fast handovers for real-time services. After a handoff, multicast data SHOULD continue to reach the mobile listener at a latency similar to unicast communication. R10 - The PMIPv6 multicast mobility management SHOULD avoid to cause packet loss in addition to unicast handoff. R11 - Multicast mobility SHOULD minimize transport costs on the forwarding link, as well as any additional overhead on the multicast Deng, et al. Expires March 20, 2009 [Page 6] Internet-Draft Multicast Requirements for PMIPv6 September 2008 delivery path. R12 - Routing convergence MUST be ensured, even when the MN moves rapidly and performs handovers at a high frequency. R13 - The protocol MUST be robust against irregular moves of the MN (e.g. ping-pong mobility) and MUST not compromise (unicast) network performance. Deng, et al. Expires March 20, 2009 [Page 7] Internet-Draft Multicast Requirements for PMIPv6 September 2008 4. Architecture requirements In addition to protocol requirements as listed in the preceeding section, mobile multicast support for listeners MAY lead to requirement on the PMIPv6 architectural entities. These potential issues are sketched in the following sub-sections: 4.1. LMA Requirements for multicast support in PMIPv6 Multicast Bandwidth Control: LMA should be able to control the total bandwidth of a user port that can be used for multicast service, thereby monitoring the fraction of the total bandwidth consumed by multicast. This requirement may lead to support a range of different service classes with various QoS requirements. Multicast session control: AAA functions resident at the LMA, in particular admission control and accounting, SHOULD be preserved and applicable under multicast services. 4.2. MAG Requirements for multicast support in PMIPv6 It is foreseeable that the MAG has to act as a multicast designated router. Hence support of MLDv2 [RFC3810] is required at the MAG. Further MAG-specific requirements can be identified: Connection Admission Control (CAC): it is required that Connection Admission Control based on available resources is supported at the MAG. Network Attachment Control: the attachment control should be supported by a multicast control function and multicast replication function. Deng, et al. Expires March 20, 2009 [Page 8] Internet-Draft Multicast Requirements for PMIPv6 September 2008 5. Security Considerations Multicast security is one of the most crucial issues in mobile multicast service such that it is required to provide security capabilities to protect mobile multicast multicast network from any malicious attempts caused by multicast security holes such as denial of service attacks. - The multicast service in PMIPv6 should not degrade the security protection of the basic PMIPv6 AAA mechanism. - Multicast system architecture is required to provide an admission control mechanism to regulate any multicast events. - Multicast system architecture is required to be independent of adjacent domains such that it shall not affect the adjacent multicast domain without permission. - Multicast system architecture is required to provide a mechanism to check integrity of multicast sources prior to service delivery such that it prevents unauthorized source to distribute multicast content. Deng, et al. Expires March 20, 2009 [Page 9] Internet-Draft Multicast Requirements for PMIPv6 September 2008 6. IANA Considerations This document makes no requests to IANA. Deng, et al. Expires March 20, 2009 [Page 10] Internet-Draft Multicast Requirements for PMIPv6 September 2008 7. Contributors This document is a result of discussions in the multicast support for PMIPv6 design team. The members of the design team that are listed below are authors that have contributed to this document: Pierrick Seite pierrick.seite@orange-ftgroup.com Peny Yang pyang@hitachi.cn Von-Hugo, Dirk Dirk.Hugo@t-systems.com Hitoshi Asaeda asaeda@sfc.wide.ad.jp Thomas C. Schmidt schmidt@informatik.haw-hamburg.de Suresh Krishnan suresh.krishnan@ericsson.com John Zhao john.zhao@huawei.com Matthias Waehlisch mw@link-lab.net Hui Deng denghui@chinamobile.com Deng, et al. Expires March 20, 2009 [Page 11] Internet-Draft Multicast Requirements for PMIPv6 September 2008 8. References 8.1. Normative References [RFC2473] Conta, A. and S. Deering, "Generic Packet Tunneling in IPv6 Specification", RFC 2473, December 1998. [RFC3810] Vida, R. and L. Costa, "Multicast Listener Discovery Version 2 (MLDv2) for IPv6", RFC 3810, June 2004. [RFC5213] Gundavelli, S., Leung, K., Devarapalli, V., Chowdhury, K., and B. Patil, "Proxy Mobile IPv6", RFC 5213, August 2008. 8.2. Informative References [MMCASTv6-PS] Schmidt, T., Waehlisch, M., and G. Fairhurst, "Multicast Mobility in MIPv6: Problem Statement and Brief Survey", draft-irtf-mobopts-mmcastv6-ps-04 (work in progress), July 2008. [PMIPv6v4] Wakikawa, R. and S. Gundavelli, "IPv4 Support for Proxy Mobile IPv6", draft-ietf-netlmm-pmip6-ipv4-support-04 (work in progress), July 2008. Deng, et al. Expires March 20, 2009 [Page 12] Internet-Draft Multicast Requirements for PMIPv6 September 2008 Authors' Addresses Hui Deng (Editor) China Mobile 53A,Xibianmennei Ave., Xuanwu District, Beijing 100053 China Email: denghui02@gmail.com Thomas C. Schmidt (Editor) HAW Hamburg Dept. Informatik Berliner Tor 7 Hamburg, D-20099 Germany Email: Schmidt@informatik.haw-hamburg.de Pierrick Seite (Editor) France Telecom 4, rue du Clos Courtel BP 91226 Cesson-Sevigne, 35512 France Email: pierrick.seite@orange-ftgroup.com Peng Yang (Editor) Hitachi 301, North Wing, Tower C Raycom Infotech Park 2 kexueyuan Nanlu Haidian District Beijing, 100080 P.R. China Phone: +861082862918(ext.)328 Email: pyang@hitachi.cn Deng, et al. Expires March 20, 2009 [Page 13] Internet-Draft Multicast Requirements for PMIPv6 September 2008 Full Copyright Statement Copyright (C) The IETF Trust (2008). 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