Network Working Group Seil Jeon Internet-Draft Soongsil University Expires: January 04, 2010 Younghan Kim Soongsil University Jaehwoon Lee Dongguk University July 04, 2009 Mobile Multicasting Support in Proxy Mobile IPv6 draft-sijeon-multimob-mms-pmip6-00.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 04, 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 Jeon, et al. Expires January 04, 2010 [Page 1] Internet-Draft Mobile Multicasting Support in PMIPv6 July 2009 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. Jeon, et al. Expires January 04, 2010 [Page 2] Internet-Draft Mobile Multicasting Support in PMIPv6 July 2009 Abstract To support IP-based group communication such as mobile IPTV in mobile environment, IP multicasting is required. Two major constraints in mobile multicasting are the tunnel convergence problem and high handover latency. To reduce the constraints, several mobile multicasting schemes based on Mobile IP have been proposed. To provide efficient mobile multicast service related to two problems, we present a multicasting architecture and fast handover scheme for Proxy Mobile IPv6 (PMIPv6). Table of Contents 1. Introduction.....................................................4 2. Conventions & Terminology........................................4 3. PMIPv6 Multicasting Architecture.................................5 4. Handover Operation...............................................6 5. Message Formats..................................................7 6. IANA Considerations..............................................7 7. Security Considerations..........................................7 8. References.......................................................7 8.1. Normative References.........................................7 Author's Address....................................................9 Jeon, et al. Expires January 04, 2010 [Page 3] Internet-Draft Mobile Multicasting Support in PMIPv6 July 2009 1. Introduction High performance of wireless technologies make multimedia streaming services possible, such as IPTV audio/video stream. These services are based on group communication, and IP multicasting is also required. Traditional IP multicast mechanisms, including multicast routing and membership management protocols, have been designed for static hosts [2]. Moreover, up to now, IP mobility protocol for mobile multicasting has depended on host-based Mobile IP variants (Mobile IP and Fast Mobile IPv6). However, Mobile IP variant protocols require modifications to an applied solution on mobile device, as well as IP reconfiguration during handoff. The Proxy Mobile IPv6 (PMIPv6) in [3] does not require any mobility-related protocol, and IP reconfiguration in the same PMIPv6 domain. With the strength of PMIPv6, several service solutions are described in [4]. However, the solution needs to solve two major constraints: the tunnel convergence problem and high handover latency [5]. Thus, we present a multicasting architecture and fast handover operation while considering the requirements for PMIPv6. 2. Terminology and Functional Components 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 RFC 2119 [1]. o Mobile Node (MN) o Previous Mobile Access Gateway (P-MAG) - The MAG that manages mobility-related signaling for an MN before handover. In this document, a MAG and Access Router (AR) are collocated o New Mobile Access Gateway (N-MAG) - The MAG that manages mobility- related signaling for the MN after handover o Multicast Router (MR) o MLD Forwarding Proxy (MF-Proxy) o PMIPv6 Multicast Context Transfer (MCT) - It is transmitted by P- MAG forecasting MN's destination N-MAG. This message includes the MN ID, the MN home network prefix, and the P-MAG IP address, and the multicast group address of the MN executing handoff. Jeon, et al. Expires January 04, 2010 [Page 4] Internet-Draft Mobile Multicasting Support in PMIPv6 July 2009 3. PMIPv6 Multicasting Architecture Multicast Core Tree : : | +----------+ +----------+ | LMA | | Local MR | +----------+ +----------+ | | |-----------------+ | | | | | +------------------| | | | | +----------+ | | +----------+ | P-MAG |---+ +----| N-MAG | |(MF-Proxy)| |(MF-Proxy)| +----------+ +----------+ : : +------+ +------+ | MN | -----> | MN | +------+ +------+ Figure 1: Multicasting architecture in PMIPv6 domain To design PMIPv6-based multicasting services, we should consider the position of the multicast router (MR). If an LMA contains the MR function, it introduces a tunnel convergence problem similar to Mobile IP variant bi-directional tunnel schemes. To solve the problem, we separated the MR function from the LMA. Moreover, if a MAG has an MR function and if a local MR is connected with MAGs, the routing update overhead degrades the performance of PMIPv6 components due to the frequent movement of the MNs. Thus, Figure 1 shows a proposed PMIPv6 multicasting architecture where the MAG contains only an MLD forwarding proxy function using the IGMP/MLD forwarding proxy [6] proposed by the IETF. This model can solve the tunnel convergence problem and reduce the routing processing overhead. In this draft, we consider only the point-to-point link between the MN and the MAG as defined in RFC 5213 [3]. Therefore, some optimized techniques are Jeon, et al. Expires January 04, 2010 [Page 5] Internet-Draft Mobile Multicasting Support in PMIPv6 July 2009 required to reduce duplicated multicasting over the point-to-point link. 4. Handover Operation MN pMAG nMAG LMA MR Multicast Tree | | | | | | | | | | | | Link->| Handover | | | | Disconnected Detection | | | | | | | | | | | |--PMIPv6-->| | | | | | Multicast | | | | | | Context | | | | | | Transfer | | | | | | | | | | | | |-MLD Membership Report>| | | | | | | | |---- L2 Attachment --->| | | | | | | | | | | | |-Proxy Binding Update->| | | | | | | | | | | | | | | | |<--Proxy Binding Ack.--| | | | | | | | | | | | | | |<--------------------------Multicast Data------------------| | | | | | | | | | | | | Figure 2: Fast multicast handover procedure using PMIPv6 Directly applying a PMIPv6 handover scheme to the proposed network model leads to service disruption due to the latency caused by the MLD query/report. To solve this problem, we proposed a fast handover scheme using the context transfer mechanism. Figure 2 shows the handover operation. When an MN hands off, the MAG with the MLD forwarding proxy predicts an MN's movement direction and transfers the multicast context message, which includes the MN ID, the MN home network prefix, the current MAG address, and the multicast group Jeon, et al. Expires January 04, 2010 [Page 6] Internet-Draft Mobile Multicasting Support in PMIPv6 July 2009 address. The N-MAG then checks whether it is receiving a node of multicast data corresponding to the group requested by the P-MAG. If this is not the case, it joins the group by sending an MLD report. 5. Message Formats To suit the format of the Proxy MIPv6 messages, PMIPv6 multicast context transfer option message is encoded according to the message data encoding rules for the Mobility Header (MH) as specified in [RFC3775]. Parameters being carried by any of these messages are encoded as message options according to the type-length-value format specified in [RFC3775]. Specified about the message and message option format are TBD. 6. IANA Considerations TBD. 7. Security Considerations This document does not discuss any special security concerns in detail. The protocol of this document is built on the assumption that all participating nodes are trusted each other as well as there is no adversary who modifies/injects false messages to corrupt the procedures. 8. References 8.1. Normative References [1] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [2] R. Vida, and L. Costa, "Multicast Listener Discovery Version(MLDv2) for IPv6," IETF RFC 3810, June 2004. Jeon, et al. Expires January 04, 2010 [Page 7] Internet-Draft Mobile Multicasting Support in PMIPv6 July 2009 [3] S. Gundavelli, K. Leung, V. Devarapalli, K. Chowdhury, and B. Patil, "Proxy Mobile IPv6", IETF RFC 5213, Augurst 2008. [4] Y. K. Zhao, P. Seite, "The Solution for PMIPv6 Multicast Service," draft-zhao-multimob-pmip6-solution-02.txt, November 2008. [5] I. Romdhani, M. Kellil, and H. Lach, "IP Mobile Multicast : Chal- lenges and Solutions," IEEE Communications Surveys & Tutorials, vol. 6, no. 1, pp. 18-41, 2004. [6] B. Fenner, H. He, B. Haberman, and H. Sandick, "Internet Group Man- agement Protocol (IGMP) / Multicast Listener Discovery (MLD)-Based Multicast Forwarding ("IGMP/MLD Proxying")", IETF RFC 4605, August 2006. Jeon, et al. Expires January 04, 2010 [Page 8] Internet-Draft Mobile Multicasting Support in PMIPv6 July 2009 Author's Addresses Seil Jeon Soongsil University 11F Hyungnam Engineering Bldg. 317, Sangdo-Dong, Dongjak-Gu, Seoul 156-743, Korea Phone: +82 2 814 0151 E-mail: sijeon@dcn.ssu.ac.kr Younghan Kim Soongsil University 11F Hyungnam Engineering Bldg. 317, Sangdo-Dong, Dongjak-Gu, Seoul 156-743, Korea Phone: +82 2 820 0904 E-mail: yhkim@dcn.ssu.ac.kr Jaehwoon Lee Dongguk University 26, 3-ga Pil-dong, Chung-gu, Seoul 100-715, KOREA E-mail: jaehwoon@dongguk.edu Jeon, et al. Expires January 04, 2010 [Page 9]