Subject: [multimob] Update draft:draft-zhang-multimob-memcast-ps-01.txt

From: "Tony" <[email-masked]>
Date: Tue, 20 Nov 2007 23:04:33 +0800

Hi every

	We have revised draft-zhang-multimob-memcast-ps-01.txt, and it will post on the web. 
   	
	Welcome to commet. :)

		Title           : MIPv6 Extensions for Mobile Multicast: Problem Statement
        Author(s)       : Jianfeng Guan, Hongke Zhang, et al.
        Filename        : draft-zhang-multimob-memcast-ps-01.txt
        Pages           : 17
        Date            : 2007-11-17
 		Abstract		:
	
		Mobile multicast is a research hotspot and gets more and more study 
    	recently. But the current existent mobility management specifications 
    	can not provide effective multicast transmission. In this memo, we 
   		discuss the problems arising from mobile multicast and address the 
    	solutions space of mobility support specifications extensions to 
    	support mobile multicast services. 

=================================================================================

 Multimob                                                Jian-feng Guan 
 Internet Draft                                           Hong-ke Zhang 
 Expires: May 2008                                           De-yun Gao 
                                                          Hua-chun Zhou 
                                                            Ya-juan Qin 
                                            Beijing JiaoTong University 
                                                      November 17, 2007

           MIPv6 Extensions for Mobile Multicast: Problem Statement 
                   draft-zhang-multimob-memcast-ps-01.txt 

 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. 

    This document may only be posted in an Internet-Draft. 

    Internet-Drafts are working documents of the Internet Engineering 
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    The list of current Internet-Drafts can be accessed at 
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    The list of Internet-Draft Shadow Directories can be accessed at 
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    This Internet-Draft will expire on May 17, . 

 Abstract 

    Mobile multicast is a research hotspot and gets more and more study 
    recently. But the current existent mobility management specifications 
    can not provide effective multicast transmission. In this memo, we 
    discuss the problems arising from mobile multicast and address the 
    solutions space of mobility support specifications extensions to 
    support mobile multicast services.  

  
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 Conventions used in this document 

    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]. 

 Table of Contents 

    1. Introduction..................................................3 
    2. Terminology...................................................3 
    3. Mobile Multicast Types........................................4 
    4. Problem Description...........................................4 
       4.1. General Issues...........................................5 
          4.1.1. Reconstruction of Multicast Delivery Tree...........5 
          4.1.2. Mobile Source Issues................................6 
          4.1.3. Mobile Receiver Issues..............................6 
          4.1.4. Mobile Forwarder Issues.............................6 
       4.2. Mobility Support Specification Issues....................6 
       4.3. Multicast Control Protocol Issues........................7 
       4.4. Multi-hop Mobile Multicast Issues........................8 
       4.5. Multihoming Mobile Multicast Issues......................8 
    5. Solutions Space Analysis......................................9 
       5.1. The Definition and Classification of Mobile Multicast....9 
       5.2. Which Entities Are Involved in Mobile Multicast?........10 
          5.2.1. How to Identify the Multicast Capacity of Forwarder?10 
          5.2.2. How to Select the Appropriate Forwarder?...........11 
       5.3. Who Initiates Mobile Multicast?.........................11 
       5.4. How to Extend Mobility Support Specifications and Multicast 
       Specifications?..............................................11 
       5.5. How to Deploy Mobile Multicast in Multihoming Environment?12 
       5.6. What Are the Mobile Multicast Security Considerations?..12 
    6. Security Considerations......................................12 
    7. IANA Considerations..........................................12 
    8. Conclusions..................................................12 
    9. Acknowledgments..............................................12 
    10. References..................................................13 
       10.1. Normative References...................................13 
       10.2. Informative References.................................13 
    Author's Addresses..............................................15 
    Intellectual Property Statement.................................15 
    Disclaimer of Validity..........................................15 
    Copyright Statement.............................................16 
    Acknowledgment..................................................16 

  
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 1. Introduction 

    Multicast technology has developed from fixed platform to mobile 
    platform. Recently, with the development of various wireless and 
    mobile technologies, mobile multicast becomes more important because 
    it can provide many applications such as mobile conference, on-line 
    game. Mobile multicast has to solve both dynamic group membership and 
    the mobility problem of multicast entity such as multicast source and 
    multicast receiver. Multicast Listener Discovery (MLD) version 1[4] 
    or version 2 [5] protocol is used to manage the dynamic membership 
    for IPv6 (IGMP [6] for IPv4), while it cannot maintain the multicast 
    states for mobile multicast entities. To solve this problem, it needs 
    to support of both link layer handover such as WLAN, WiMAX, UMTS and 
    network layer handover such as MIPv6 [2] and its variants such as 
    FMIPv6 [11], HMIPv6 [12]and NEMO [3]. However, these specifications 
    cannot provide an effective mechanism to support mobile multicast.  

    MIPv6 is designed to support unicast communication by caching the 
    binding between HoA and CoA of MN, and route the packets addressed to 
    HoA to CoA transparently. For the multicast packets, two basic 
    methods, Bi-directional Tunnel (BT) and Remote Subscribe (RS) methods 
    were proposed. BT is transparent and has lower join latency, but 
    introduces triangular routing and additional transmission overheads. 
    While RS has effective routing, but increases long join delay 
    especially when foreign networks do not have the multicast states of 
    MN interested, and even result in multicast service disruption if 
    foreign networks do not support multicast. Based on BT and RS, 
    several improved schemes were proposed in past few years [13], and 
    try to make the tradeoff between BT and RS, using different multicast 
    agent selection algorithms or modifying the mobility support 
    specifications. According to [14], the current mobile multicast 
    schemes can be classified into three kinds, BT based methods, RS 
    based methods and Agent based methods.  

    The prime problem of mobile multicast is that the current mobility 
    support specifications such as MIPv6 can not provide effective 
    multicast transmission mechanism. The binding cache in MIPv6 only 
    records the mapping between HoA and CoA which can be used to reroute 
    the unicast packets directly. However, for multicast data, no such 
    mechanism is defined. So, in this memo, we specify the problems for 
    MIPv6 extensions of mobile multicast and describe the potential 
    solutions space.  

 2. Terminology 

    The terminology used in this memo is already defined in MIPv6, FMIPv6, 
    HMIPv6 and NEMO. 

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 3. Mobile Multicast Types 

    Figure 1 shows the classification of mobile multicast based on the 
    entities involved in multicast, which includes three basic mobile 
    types, mobile source, mobile receiver and mobile forwarder. Mobile 
    forwarder is the node in the multicast delivery tree. For example, 
    Mobile IP based multicast is typical mobile source or receiver types, 
    and the NEMO multicast and MANET multicast are mobile forwarder type.  

                          +---+                  --+ 
            Mobile source | S |--->move            | 
                          +---+                    +-> MLD protocol 
                            |                      | 
                    +-------+--------+             | 
                    |                |           --+ 
         Mobile   +---+            +---+           | 
        Forwarder | R |--->move    | R |           | 
                  +---+            +---+           | 
                    |                |             +-> Multicast 
              +-----+-----+          |             | Routing protocol 
              |           |          |             | 
            +---+       +---+      +---+           | 
            | R |       | R |      | R |           | 
            +---+       +---+      +---+         --+ 
                          |                        | 
                  +-------+-------+                | 
                  |       |       |                +-> MLD protocol 
                +---+   +---+   +---+     Mobile   | 
                | H |   | H |   | H |---> Receiver | 
                +---+   +---+   +---+            --+ 
           +----------------------------------+ 
           | H: host    R: Router    S: source| 
           +----------------------------------+ 
       
                  Figure 1 Mobile multicast classification 

 4. Problem Description 

    Mobile multicast derives from the development of Mobile IP and 
    multicast technology, and current mobile multicast schemes are mainly 
    based on the combination of fixed multicast and mobility support 
    specifications. So, the mobile multicast problems come from two parts, 
    one is fixed multicast and the other one is mobility support 
    specifications.  

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    Multicast provides an effective group communication mechanism in IP 
    layer to reduce the redundant packets transmission compared with the 
    unicast. Fixed multicast is based on host group model [7] which 
    consists of multicast route protocol and multicast group control 
    protocol. Multicast routing protocols constructs the multicast 
    delivery tree and maintains the multicast states in multicast routers, 
    while multicast control protocol is used by multicast router and host 
    to exchange the multicast membership information. For the different 
    mobile types, the current multicast routing protocols only support 
    dynamic membership and cannot support mobile group members. When a 
    group member moves into another subnet, it has to rebuild its 
    multicast states by itself or the other entities.  

 4.1. General Issues 

    Traditional multicast routing protocols have been designed for static 
    network topology and the multicast delivery tree is stable or little 
    changed. For mobile multicast, these assumptions changed. Directly 
    applying traditional multicast route protocols to mobile scenario may 
    result in multicast session disruption. To improve the performance of 
    multicast services, it has to solve the following problems.  

 4.1.1. Reconstruction of Multicast Delivery Tree 

    The foundational problem in mobile multicast is the reconstruction of 
    multicast delivery tree. There are two kinds of multicast delivery 
    trees, source-based tree such as DVMRP [15], MOSPF [8], PIM-DM [16] 
    and PIM-SSM, and shared tree such as PIM-SM [9] and CBT [17]. Source-
    based protocols construct optimal multicast delivery trees for every 
    source in a group. While shared tree protocols construct a RP or Core 
    based multicast delivery tree for a group. Figure 2 shows the 
    influence of mobile multicast with SPT and RPT. Different multicast 
    delivery trees affect different nodes. In more complicated scenario 
    with multiple mobile multicast types, the performance of mobile 
    services will degrade significantly.  

      +=========================================================+ 
      |     | Mobile Source | Mobile Forwarder| Mobile Receiver | 
      +=====+===============+=================+=================+ 
      | SPT |      ALL      |     PART        |        ONE      | 
      +-----+---------------+-----------------+-----------------+ 
      | RPT |      ALL      |     PART        |        ONE      | 
      +-----+---------------+-----------------+-----------------+ 
     
        Figure 2  The influence of Mobile multicast using SPT and RPT 

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 4.1.2. Mobile Source Issues 

    Once source changes its attachment, it will affect all receivers in 
    the group. The first problem is the multicast data transmission mode. 
    If the current AR supports multicast or MLD proxy with multicast 
    forwarding, mobile source MAY transmit the native multicast packets. 
    Or else, it MUST transmit the multicast packets encapsulated in 
    unicast. The second problem is to hide mobility. To be transparent 
    for the other nodes, mobile source SHOULD use the HoA as the source 
    address of multicast data. However, using the HoA will result in the 
    ingress filtering problem and RPF check failure. The third problem is 
    when mobile source is out of the scope of group, AR will discard the 
    multicast packets as it will take the source as a strange node.  

 4.1.3. Mobile Receiver Issues  

    Once receiver changes its attachment, it only affects itself. The 
    multicast packets will be loss and out-of-order, which result in 
    service disruption.  

    Firstly, mobile receiver SHOULD shorten the leave delay and rejoin 
    delay as possible as it can. To reduce the leave delay can alleviate 
    the overhead of multicast forwarder, while to shorten the rejoin 
    delay will reduce the packet loss. Secondly, it SHOULD support the 
    duplication packet detection (DPD) and packet realignment. After 
    mobile receiver handover from one subnet to another subnet, it will 
    get the duplicated and disordered multicast packets, which will 
    degrade the performance of mobile multicast services.  

 4.1.4. Mobile Forwarder Issues  

    Once forwarder changes its attachment, it will affect all the 
    multicast traffic on the path. The multicast forwarder MAY be the 
    Mobile Router in NEMO or the forward node in MANET multicast. 
    Moreover, it also can be the RP when PIM-SM is used. Although mostly 
    mobile multicast schemes only focus on the mobility in the access 
    networks, the mobility in the middle should also be considered.  

 4.2. Mobility Support Specification Issues 

    Mobile IP provides handover management and location management for 
    mobile entity, and it sets up the binding cache between HoA and CoA 
    to support the transparent unicast transmission. However, it does not 
    provide mechanisms to enable multicast session to survive handover.  

    Firstly, MIPv6 should not only record the unicast binding cache, but 
    also record the multicast binding cache to assist the mobile 

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    multicast. Multicast binding cache may include the group address, 
    source lists, filter mode and interface identifier. It records the 
    membership information from the tunneled MLD messages or extended 
    signaling and gets the MN information from unicast binding cache. The 
    Multicast binding cache can be located in the HA or the other entity 
    such as Rendezvous Point in PIM-SM.  

    Secondly, Multicast session consists of multicast data and group 
    control messages transmission. As described in MIPv6, to support 
    mobile multicast, HA should be a full IPv6 multicast router or have 
    the proxy MLD function coupled with kernel multicast forwarding. 
    However, MIPv6 does not define the detailed mechanisms and the 
    functional requirements for HA and MN. To support the seamless 
    multicast handover, HA should cooperate the mobility support 
    specifications with multicast routing protocol or proxy MLD, and sets 
    up the multicast information for MN and transmits the native 
    multicast packets between HA and MN. Mobile support specification 
    SHOULD maintain both of them. When HA receives the MLD message form 
    the unicast tunnel or upstream interface, it SHOULD distinguish the 
    owner of MLD messages. While MN SHOULD send the MLD messages to HA 
    through tunnel or to AR through physical interface, respectively.  

    Thirdly, Mobile IP based mobile multicast schemes have to solve the 
    route optimization problem. To optimize multicast route, we need an 
    effective multicast forwarder or agent selection mechanism. BT and RS 
    are two basic selection methods. BT based methods use the bi-
    directional tunnel to transmit the multicast data between old 
    location and new location of mobile entity. While using IP tunnels 
    involves multiple encapsulation and de-capsulation operations which 
    require an extra cost of CPU time and memory, and increase the 
    multicast packet size which causes fragmentation and large bandwidth 
    consumption. RS based methods rejoin the multicast delivery tree in 
    new location, but introduce additional join delay, which includes L2 
    and L3 handover delay, multicast membership protocol delay, multicast 
    delivery tree computation delay, and the increased propagation delay. 
    It degrades the performance of multicast services. Agent based 
    methods introduce new entity and use different selection algorithms 
    to balance between BT and RS, but increase the complexity. So, 
    mobility support specifications need solve multicast route 
    optimization problem.  

 4.3. Multicast Control Protocol Issues 

    Multicast router uses the IGMP/MLD as the multicast group control 
    protocol to discovery the multicast subscribers, and the host uses 
    the IGMP/MLD to join and leave the group. IGMP/MLD protocol is 
    designed for fixed nodes, and only support dynamic group membership, 

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    but not considers the mobility of nodes. To support the mobile 
    multicast, IGMP/MLD protocol has to solve the following problems.  

    Firstly, mobile entity has to send unsolicited IGMP/MLD report 
    message immediately after detecting the movement to shorten the 
    rejoin delay. Secondly, IGMP/MLD messages are link-local, destined to 
    a link-scope multicast address and have a hop limit of 1 and can not 
    forward to the other subnets. When mobile multicast subscriber moves 
    into another subnet, it has to reconstruct multicast states in the 
    new location. However, the IGMP/MLD protocol does not provide this 
    mechanism. Thirdly, IGMP/MLD protocol only records the multicast 
    membership information for every link not the node, which can reduce 
    the number of multicast states in shared link such 802.11. But for 
    some point-to-point links such as UMTS, HA assigns a home link prefix 
    that is unique for each MN and HoA is assigned from this unique 
    prefix. As a result, it makes a link for each MN. So the multicast 
    behavior could be simplified. Extend the IGMP/MLD to record multicast 
    state for MN in point-to-point link is preferable.  

 4.4. Multi-hop Mobile Multicast Issues 

    The current mobile multicast schemes mainly are single-hop based, and 
    the distance between mobile multicast subscribers and the AR is one 
    hop. However, mobile network multicast such as NEMO multicast and 
    MANET multicast interworking with the fixed networks is multi-hop. 
    For NEMO multicast, the node in the mobile network such as LFN, VMN 
    joins the multicast group through MR which may be multi-hop to the 
    access networks. IGMP/MLD messages and multicast packets can not be 
    forwarded if the router in the path to AR does not support the 
    multicast function. Especially when nesting happens, the multicast 
    packets transmission will suffer from large overheads and additional 
    propagation delay, which result in degradation of multicast services. 
    For the MANET multicast interworking with the fixed networks, every 
    node in the MANET may be dynamic and get the connection through 
    multiple nodes as forwarders. Because the mobile devices have limited 
    bandwidth, power, and coverage, the multi-hop mobile multicast scheme 
    should be light-weight. How to provide multicast service for these 
    nodes in the mobile network should be considered in the further 
    mobile multicast schemes. 

 4.5. Multihoming Mobile Multicast Issues 

    Most mobile multicast methods including mobile network multicast are 
    based on single network interface and connect to one AR at a time, 
    which results in the mobile entity having to break the connection to 
    the current network before reattaching itself to the new network 
    (Break-Before-Make) [18]. The reason is that the current wireless 

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    network interfaces of mobile devices are incapable of listening to 
    multiple base stations. As a result, the multicast session will be 
    disrupted because of the serious packet loss. Recently, more and more 
    mobile devices have multiple network interfaces and can support more 
    than one Internet connections at a time. Using multiple interfaces 
    can provide Make-Before-Break handoffs                , ubiquitous 
    access, redundancy, load balancing. However, realizing the 
    multihoming mobile multicast has to consider the problems inheriting 
    from the MIPv6 multihoming [19]. While it still have some problems. 
    Firstly, current mobility support specifications do not support MN to 
    bind multiple CoAs in HA and CN. Secondly, it needs a multicast 
    traffic distribution mechanism which includes the interface selection, 
    HoA and CoA selection. When multiple paths are available, MN should 
    choose a suitable one to transmit the multicast packets. If current 
    path fails, MN should redirect the flow to the new path. Besides, to 
    balance the multicast traffic among multiple interfaces, MN should 
    set up a load balance mechanism.  

 5. Solutions Space Analysis 

    As described in Section 4, Mobile multicast faces many challenges. In 
    this section, we try to analyze the solution space based on following 
    questions:  

    o The definition of mobile multicast.  

    o Which entities are involved in mobile multicast? 

    o Who initiates mobile multicast? 

    o How to extend mobility support specification and multicast 
       specifications? 

    o How to deploy the mobile multicast under multihoming? 

    o What are the mobile multicast security considerations? 

 5.1. The Definition and Classification of Mobile Multicast 

    In this memo, the mobile multicast means the IP multicasting in 
    mobile environments based on various mobility support specifications, 
    which include MIPv4/6, FMIPv4/6, HMIPv4/6, NEMO4/6 and various MANET 
    unicast and multicast protocols. According to section 3, mobile 
    multicast has three basic types, mobile source, mobile receiver and 
    mobile forwarder. In some scenarios, multiple mobile types may 
    coexist which is more complicated to provide mobile multicast 
    services.  

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 5.2. Which Entities Are Involved in Mobile Multicast? 

    There are many combinations of entities involved in mobile multicast 
    at different application scenarios. Figure 3 shows the entities 
    involved in three mobile multicast types.  

           +=========================+===+===+===+===+===+===+ 
           |                 | MSS   | S | R | F | HA| AR| MR| 
           +-----------------+-------+---+---+---+---+---+---+ 
           |                 | MIP   | Y | N | Y | Y | Y | O | 
           |                 +-------+---+---+---+---+---+---+ 
           |Mobile Source    | NEMO  | Y | N | Y | Y | Y | Y | 
           |                 +-------+---+---+---+---+---+---+ 
           |                 | MANET | Y | N | Y | O | O | O | 
           +-----------------+-------+---+---+---+---+---+---+ 
           |                 | MIP   | N | Y | Y | Y | Y | O | 
           |                 +-------+---+---+---+---+---+---+ 
           |Mobile Receiver  | NEMO  | N | Y | Y | Y | Y | Y | 
           |                 +-------+---+---+---+---+---+---+ 
           |                 | MANET | N | Y | Y | O | O | O | 
           +-----------------+-------+---+---+---+---+---+---+ 
           |                 | MIP   | N | N | Y | Y | Y | O | 
           |                 +-------+---+---+---+---+---+---+ 
           |Mobile Forwarder | NEMO  | N | N | Y | Y | Y | Y | 
           |                 +-------+---+---+---+---+---+---+ 
           |                 + MANET | N | N | Y | O | O | O | 
           +=================+=======+===+===+===+===+===+===+ 
           S ?Source      R ?Receiver   MR ?Mobile Router 
           F ?Forwarder   Y ?Yes        N ?No   O ?Not a Issue 
     
                  Figure 3 Mobile multicast classification 

    Every entity involved has different function requirement, and they 
    have to cooperate to finish mobile multicast. The key entity in 
    mobile multicast is the forwarder node (sometimes also called agent), 
    which may be HA, AR, MR, or any other node with multicast capacity. 
    So, there are two questions left to be solved.  

 5.2.1. How to Identify the Multicast Capacity of Forwarder? 

    Multicast capacity means the node supports multicast routing or 
    IGMP/MLD Proxying to forward multicast packets. B. Haberman and J. 
    Martin [10] propose Multicast Router Discovery (MRD), a general 
    mechanism to discovery the multicast routers. MRD introduces 
    Multicast Router Advertisement (MRA) and Multicast Router 
    Solicitation (MRS) to detect the IP multicast forwarding ability of a 

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    router. MRD protocol can be used in mobile multicast to detect the 
    multicast capacity of involved entities.  

 5.2.2. How to Select the Appropriate Forwarder? 

    After detecting the multicast capacity of forwarder, we need to 
    select one forwarder or more to optimize mobile multicast performance. 
    For example, in BT based methods HA is selected as the forwarder, it 
    will record the multicast states and forward multicast packets. In RS 
    based methods, the current AR is selected as the forwarder. While in 
    agent based methods, multiple forwarders are selected in succession 
    with the movement of mobile entity. It seems that we need to define 
    an effective forwarder selection algorithm.  

 5.3. Who Initiates Mobile Multicast? 

    Mobile multicast is based on mobility support specifications. Similar 
    to the handoff procedure it has different initiator. There are three 
    kinds of handoff initiation mechanisms, mobile-controlled, network-
    controlled and mobile-assisted [23]. Mostly mobility support 
    specifications such as MIP and NEMO are host-based, and the mobile 
    entity firstly detects the movement and then initiates the mobile 
    multicast, whereas the others mobility support specifications such as 
    Proxy MIP [24] are network based, and the network in charge of the 
    mobility management. When deploy mobile multicast services, the first 
    problem we need to consider is the multicast handoff initiator. To 
    advance the performance of mobile multicast, the earlier discovery of 
    mobility is preferential.  

 5.4. How to Extend Mobility Support Specifications and Multicast 
    Specifications? 

    The current mobility support specifications and multicast protocols 
    do not support the mobile multicast in nature. On one hand, multicast 
    data is traded as unicast data in mostly mobility support 
    specification. As a result to support effective mobile multicast, 
    most mobile multicast schemes have to extend the mobility support 
    specifications. Based on MIP, many schemes record multicast states 
    for mobile entity in HA or the other nodes. While, FMIP based schemes 
    most add multicast information in signaling messages such as FBU and 
    HI. While in HMIP based schemes, MAP function entity is extended to 
    have more multicast capacity. On the other hand, IGMP/MLD is also 
    extended to record or transfer the multicast states context for 
    mobile entity.  

  
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 5.5. How to Deploy Mobile Multicast in Multihoming Environment? 

    Most mobile entity has multiple Internet connections and attaches to 
    multiple networks at one time, which have different coverage, bite 
    rate, bandwidth. How to implement mobile multicast in multihoming 
    scenarios is important to provide the seamless mobile multicast 
    handover. Current most mobile multicast schemes based on single 
    network interface to perform multicast handover, which is less stable 
    and reliable. Once mobile entity lost its connection, it will have a 
    significant impact on performance of mobile multicast services. 
    Recently, the multihoming issues in MIPv6 [19] [20] and NEMO [21] 
    were discussed. MN with multiple addresses which allocated to either 
    a single interface or multiple interfaces can provide ubiquitous, 
    permanent and fault-tolerant access to the Internet [22]. The 
    multihoming techniques used for mobile multicast can ensure global 
    connectivity and minimizes the disruption time. However, to deploy 
    mobile in multihoming, we need to solve the problems such as 
    multicast traffic distribution, multiple interfaces management and 
    mobile multicast handover management.  

 5.6. What Are the Mobile Multicast Security Considerations? 

    TBD  

 6. Security Considerations 

    This memo discusses the MIPv6 extensions for mobile multicast. 
    Security issues arise from the extensions of mobility support 
    specifications and MLD protocols.  

 7. IANA Considerations 

    There are no IANA considerations introduced by this memo. 

 8. Conclusions 

    This memo discusses the problems arise from the mobile multicast over 
    MIPv6 variants, and describes some solutions.  

 9. Acknowledgments 

    The authors would like to thank Behcet Sarikaya (Huawei USA), Thomas 
    C. Schmidt (HAW Hamburg), Hesham Soliman (Elevate Technologies), Si-
    Dong Zhang, Hongbin Luo (BJTU NGIRC) for their valuable comments and 
    suggestions on this memo. 

  
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 10. References 

 10.1. Normative References 

    [1]  Bradner, S., "Key words for use in RFCs to Indicate Requirement 
          Levels", BCP 14, RFC 2119, March 1997. 

    [2]  D. Johnson, C. Perkins and J. Arkko, "Mobility Support in IPv6", 
          RFC 3775, June 2004. 

    [3]  V. Devarapalli, R. Wakikawa, A. Petrescu, P. Thubert, "Network 
          Mobility (NEMO) Basci Support Protocol", RFC 3963, January 2005. 

    [4]  S. Deering, W. Fenner, B. Haberman, "Multicast Listener 
          Discovery (MLD) for IPv6", RFC 2710, October 1999.  

    [5]  R. Vida, L. Costa, "Multicast Listener Discovery Version 2 
          (MLDv2) for IPv6", RFC 3810, June 2004. 

    [6]  W. Fenner, "Internet Group Management Protocol, Version 2", RFC 
          2373, July 1997. 

    [7]  S. Deering, "Host Extensions for IP Multicasting", RFC 1112, 
          August 1989. 

    [8]  J. Moy, "Multicast Extensions to OSPF", RFC 1584, March 1994.  

    [9]  Bill Fenner, Mark Handley etc, "Protocol Independent Multicast-
          Sparse Mode (PIM-SM): Protocol Specification (Revised) ", RFC 
          4601, August 2006. 

    [10] B. Haberman and J. Martin, "Multicast Router Discovery", RFC 
          4286, December 2005.  

 10.2. Informative References 

    [11] R. Koodli, "Fast Handovers for Mobile IPv6", RFC 4068, July 
          2005. 

    [12] H. Soliman, C. Castelluccia, K. EI Malki, L. Bellier, 
          "Hierarchical Mobile IPv6 Mobility Management (HMIPv6)", RFC 
          4140, August 2005. 

    [13] Romdhani, I., Kellil, M., Lach, H.-Y. et al., "IP Mobile 
          Multicast: Challenges and Solutions", IEEE Comm. Surveys, 6(1), 
          2004. 

 Zhang, Guan et al.      Expires May 17, 2008                 [Page 13] 

 Internet-Draft               MEMCAST-PS                  November 2007 

    [14] Thomas C. Schmidt, Matthias Waehlisch, "Multicast Mobility in 
          MIPv6: Problem Statement and Brief Survey", draft-irtf-mobopts-
          mmcastv6-ps-01, November 2007. 

    [15] D. Waitzman, C. Partridge, S. Deering, "Distance Vector 
          Multicast Routing Protocol", RFC 1075, November 1988. 

    [16] A. Adams, J. Nicholas, W. Siadak, "Protocol Independent 
          Multicast ?Dense Mode (PIM-DM): Protocol Specification 
          (Revised)", RFC 3973, January 2005.  

    [17] A. Ballardie, "Core Based Trees (CBT version 2) Multicast 
          Routing" ?Protocol Specification, RFC 2189, September 1997. 

    [18] Petander H., Perera E., Seneviratne A., "Multiple Interface 
          Handoffs: A Practical Method for Access Technology Independent 
          Make-Before-Break Handoffs", NICTA Technical Report, July 2005, 
          http://nicta.com.au/uploads/documents/PA005092_NICTA1.pdf 

    [19] N. Montavount, R. Wakikawa, T. Ernst et al., "Analysis of 
          Multihoming in Mobile IPv6", draft-ietf-monami6-mipv6-analysis-
          02, work in progress, February 2007.  

    [20] Ernst, T., "Motivations and Scenarios for Using Multiple 
          Interfaces and Global Addresses", draft-ietf-monami6-
          multihoming-motivation-scenario-01, work in progress, Oct. 2006.  

    [21] C. Ng, T. Ernst, E. Paik, M. Bagnulo, "Analysis of Multihoming 
          in Network Mobility Support", draft-ietf-nemo-multihoming-
          issues-07, work in progress, February 2007. 

    [22] Zhang Hongke et al., "Multiple Interface Mobile Multicast", 
          draft-zhang-monani6-multipleif-mcast-00, work in progress, July 
          2007. 

    [23] Farhan Siddiqui and Sherali Zeadally, "Mobility Management 
          across Hybird Wireless Networks: Trends and Challenges", 
          Computer Communications 29 (2006) 1363-1285, Elsevier publish, 
          2006. 

    [24] S. Gundavelli, K. Leung, V. Devarapalli, K. Chowdhury and B. 
          Patil, "Proxy Mobile IPv6", draft-sgundave-mip6-proxymip6-02, 
          work in progress, March 2007.  

  
 Zhang, Guan et al.      Expires May 17, 2008                 [Page 14] 

 Internet-Draft               MEMCAST-PS                  November 2007 

 Author's Addresses 

    Hong-ke Zhang, Jian-feng Guan, De-yun Gao, Hua-chun Zhou, Ya-juan Qin 
    Next Generation Internet Research Center (NGIRC), Beijing JiaoTong 
    University  
    Beijing, China, 100044 
       
    Phone: +86 10 51685677 
    Email: [email-masked] 
           [email-masked] 
           [email-masked] 
           [email-masked] 
           [email-masked] 

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 Zhang, Guan et al.      Expires May 17, 2008                 [Page 15] 

 Internet-Draft               MEMCAST-PS                  November 2007 

 Copyright Statement 

    Copyright (C) The IETF Trust (2007). 

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 Zhang, Guan et al.      Expires May 17, 2008                 [Page 16] 

　　　　　　　　Tony
　　　　　　　　[email-masked]
　　　　　　　　　　2007-11-20
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