Internet Area M.Hui Internet Draft H.Deng Intended status: Informational D.Liu Expires: Sep. 13, 2012 China Mobile March 13, 2012 Fast Handover for Multicast in Proxy Mobile IPv6 draft-hui-multimob-fast-handover-04 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 Jan 01, 2011. 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 (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Hui & Chen & Deng Expires Jan 01, 2011 [Page 1] Internet-Draft Fast Handover for Multicast July 2010 Abstract This document specifies the predictive fast handover mechanism to solve the problem of handover latency and packet loss in Proxy Mobile IPv6 Multicast. Necessary extensions are specified for Handover Initiate (HI) and Handover Acknowledgement (HAck) messages to support multicast handover procedure. Hui&Chen&Deng Expires Jan 01, 2011 [Page 2] Internet-Draft Fast Handover for Multicast July 2010 Table of Contents 1. Introduction................................................4 2. Problem Statement...........................................5 3. Terminology.................................................6 4. Protocol Operation..........................................7 5. Message Format.............................................11 6. Security Considerations.....................................13 7. IANA Considerations........................................14 8. References.................................................15 8.1. Normative References...................................15 8.2. Informative References.................................15 Author's Addresses............................................16 Hui&Chen&Deng Expires Jan 01, 2011 [Page 3] Internet-Draft Fast Handover for Multicast July 2010 1. Introduction Proxy Mobile IPv6 (PMIPv6) protocol provides local mobility management to a mobile node without requiring any modification of the mobile node. The Local Mobility Anchor (LMA) and Mobile Access Gateway (MAG) perform the mobility management signaling on behalf of the mobile node. Extensions for LMA and MAG are specified in [1] to support IP multicast in PMIPv6. Nevertheless, the basic performance including handover latency and packet loss is not considered different form that of PMIPv6. Fast handover for Mobile IPv6 is specified in [2]. [3] extends the FMIPv6 and applies it to the PMIPv6 in order to decrease handover latency and packet loss as well as transfer of network-resident contexts. However, IP multicast is not considered in fast handover for PMIPv6. We propose a fast handover mechanism to support multicast for PMIPv6. Necessary extensions are specified in HI and HAck message to transfer the multicast node's context information and deliver the multicast data before the set up of tunnel between n-MAG and LMA. Hui&Chen&Deng Expires Jan 01, 2011 [Page 4] Internet-Draft Fast Handover for Multicast July 2010 2. Problem Statement The existing solution for PMIPv6 multicast [1] specifies that, only after the bi-directional tunnel is built between n-MAG and LMA using extended PBU (PBU-M) message, the multicast packet can be continuously delivered to MN. It inevitably causes the latency and loss of packet during handover process. The solution presents two ways to acquire the MN's profile, which includes MN' ID and multicast state information. One way is to use the Context Transfer Protocol (CXTP) [4] to transfer MN's profile from p-MAG to n-MAG. In the other way, if MN's profile is stored in a policy store [5], n-MAG obtains MN's multicast state by the same mechanism used to acquire MN' ID and profile during MN's attachment process [5]. In another PMIPv6 multicast solution [6], the author proposes normal handover and fast handover for proxy mobile multicast service. There is no any optimization in normal handover, the handover involves MN by running the MLDv2 [7] protocol with n-MAG to receive the related multicast packet. In the fast handover procedure, similar to the first method used in [1],the context transfer is used to provide multicast information. Although n-MAG can acquire the MN' multicast information before MN handovers to it, only after n-MAG joins the multicast group, it can receive the multicast data. Hui&Chen&Deng Expires Jan 01, 2011 [Page 5] Internet-Draft Fast Handover for Multicast July 2010 3. Terminology This document refers to [1] [2] [3] for terminology. The following terms and abbreviations are additionally used in this document. The reference network is illustrated in Figure 1. Previous Mobile Access Gateway (p-MAG): The MAG that manages mobility related signaling for the MN before handover. New Mobile Access Gateway (n-MAG): The MAG that manages mobility related signaling for the MN after handover. HO-Initiate: A generic signaling that indicates the handover of the MN sent from the MN to the p-MAG. It is assumed that HO-Initiate can carry the information to identify the MN and to assist the p-MAG to resolve the n-MAG. Hui&Chen&Deng Expires Jan 01, 2011 [Page 6] Internet-Draft Fast Handover for Multicast July 2010 4. Protocol Operation The architecture of fast handover for multicast in Proxy Mobile IPv6 is shown in Figure 1. A multicast tunnel is established to transfer the multicast data from p-MAG to n-MAG before the n-MAG joins the multicast group, so that whenever the MN handovers to the n-MAG, it can receive the multicast data from n-MAG. +----------+ | LMA | | | +----------+ / \ / \ / \ +........../..+ +..\..........+ . +-------+-+ .______. +-+-------+ . . | p-MAG |()_______)| n-MAG | . . +----+----+ . . +----+----+ . . | . . | . . | . . | . . +----+ . . +----+ . . | MN | ----------> | MN | . . +----+ . . +----+ . +.............+ +.............+ Figure 1: Reference network for fast handover In order to decrease the handover latency and packet loss, this document specifies a bi-directional tunnel between the Previous MAG (p-MAG) and the New MAG (n-MAG). As the n-MAG needs the multicast node's context information to set up a bi-directional tunnel to continuous deliver multicast packet to mobile node, the HI and HAck messages are extended to support mobile multicast node's context transfer, in which parameters such as MN ID, MN Multicast State, are transferred from the p-MAG to the n-MAG. The sequence of events illustrating the fast handover for multicast is shown in Figure 2. MN p-MAG n-MAG LMA | | | | (1) | HO Initiate | | | | --(MN ID,-->| | | Hui&Chen&Deng Expires Jan 01, 2011 [Page 7] Internet-Draft Fast Handover for Multicast July 2010 | n-MAG ID) | | | (2) | | HI | | | | --(MN ID, --> | | | MN Multicast State) | | | | | (3) | | <---HAck--- | | | | (MN ID) | | | | | | | | HI/HAck | | (4) | |<------------->| | | | | | (5) | | M data | | | |====tunnel====>| | (6) ~~~ | | | ~~~ | | | | | | | (7) |<==========M data============| | | | | | (8) | | |------PBU-M------->| | | | | (9) | | |<-----PBA----------| | | | | (10) | | | M data | | | |<==bi-dir tunnel==>| Hui&Chen&Deng Expires Jan 01, 2011 [Page 8] Internet-Draft Fast Handover for Multicast July 2010 | | | | (11) | | HI/HAck | | | |<------------->| | | | | | Figure 2: Fast handover for PMIPv6 multicast The detailed descriptions are as follows: (1)The MN detects that a handover is imminent and reports the MN ID and n-MAG ID. (2)The p-MAG sends the HI to the n-MAG. The HI message includes MN ID and MN Multicast State. (3)The n-MAG sends the HAck back to the p-MAG. (4)The n-MAG requests the p-MAG to forward multicast packets by setting F flags in the HI message. (5)A tunnel is established between the p-MAG and n-MAG and multicast packets destined for the MN are forwarded from the p-MAG to the n-MAG over this tunnel. (6)The MN undergoes handover to n-MAG. (7)The n-MAG starts to forward multicast packets destined for the MN. (8)The n-MAG sends the Proxy Binding Update with multicast extension (PBU-M)(proposed in [1]) to the LMA. (9)The LMA sends back the Proxy Binding Acknowledgment (PBA) to the n-MAG. (10)A bi-directional tunnel is set up for forwarding corresponding multicast data. Hui&Chen&Deng Expires Jan 01, 2011 [Page 9] Internet-Draft Fast Handover for Multicast July 2010 (11)Multicast packet forwarding is completed between p-MAG and n-MAG. Hui&Chen&Deng Expires Jan 01, 2011 [Page 10] Internet-Draft Fast Handover for Multicast July 2010 5. Message Format This document defines new Mobility Header messages for the extended HI and HAck and new mobility options for delivering context information. 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +---------------+-+-+-----------+ | Code |U|F|M| Reserved| +-------------------------------+---------------+-+-+-----------+ | Reserved | Identifier | +-------------------------------+-------------------------------+ | | . . . Mobility options . . . | | +---------------------------------------------------------------+ Figure 3: HI Mobility Header message with multicast extension A new flag (M) is included in the HI Mobility Header message with multicast extension. The rest of the message format remains the same as defined in [3]. When (M) flag is specified in HI Mobility Header message, the mobility options field needs to be extended to include the multicast addresses. 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Record Type | Aux Data Len | Number of Sources (N) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | * * | | * Multicast Address * | | * * | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | * * | | * Source Address [1] * Hui&Chen&Deng Expires Jan 01, 2011 [Page 11] Internet-Draft Fast Handover for Multicast July 2010 | | * * | | +- -+ | | * * | | * Source Address [2] * | | * * | | +- -+ . . . . . . . . . +- -+ | | * * | | * Source Address [N] * | | * * | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | . . . Auxiliary Data . . . | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Hui&Chen&Deng Expires Jan 01, 2011 [Page 12] Internet-Draft Fast Handover for Multicast July 2010 6. Security Considerations TBD. Hui&Chen&Deng Expires Jan 01, 2011 [Page 13] Internet-Draft Fast Handover for Multicast July 2010 7. IANA Considerations This document does not require any IANA action. Hui&Chen&Deng Expires Jan 01, 2011 [Page 14] Internet-Draft Fast Handover for Multicast July 2010 8. References 8.1. Normative References [1] H. Asaeda, P. Seite, J. Xia, "PMIPv6 Extensions for Multicast", draft-asaeda-multimob-pmip6-extension-01.txt (work in progress), July 2009. [2] Koodli, R., Ed., "Mobile IPv6 Fast Handovers", RFC 5268, June 2008. [3] H. Yokota, K. Chowdhury, R. Koodli, B. Patil, F. Xia, "Fast Handovers for Proxy Mobile IPv6", draft-irtf-mipshop-pfmipv6-00.txt (work in progress), October 2008. [4] Loughney, Ed., J., Nakhjiri, M., Perkins, C., and R. Koodli,"Context Transfer Protocol (CXTP)", RFC 4067, July 2005. [5] Gundavelli, S, Ed., Leung, K., Devarapalli, V., Chowdhury, K.,and B. Patil, "Proxy Mobile IPv6", RFC 5213, August 2008. [6] Y K. ZHAO, P. Seite, "The Solution for Pmipv6 Multicast Service", draft-zhao-multimob-pmipv6-solution-02.txt (work in progress), November 2008. [7] Vida, R. and L. Costa, "Multicast Listener Discovery Version 2 (MLDv2) for IPv6", RFC 3810, June 2004. 8.2. Informative References Hui&Chen&Deng Expires Jan 01, 2011 [Page 15] Internet-Draft Fast Handover for Multicast July 2010 Author's Addresses Min Hui China Mobile 53A,Xibianmennei Ave., Xuanwu District, Beijing 100053 China Email: huimin.cmcc@gmail.com Hui Deng China Mobile 53A,Xibianmennei Ave., Xuanwu District, Beijing 100053 China Email: denghui02@gmail.com Dapeng Liu China Mobile 53A,Xibianmennei Ave., Xuanwu District, Beijing 100053 China EMail: liudapeng@chinamobile.com Hui&Chen&Deng Expires Jan 01, 2011 [Page 16]