MULTIMOB Group H. Asaeda
Internet-Draft NICT
Intended status: Standards Track P. Seite
Expires: April 25, 2013 France Telecom
October 22, 2012
Multicast Routing Optimization by PIM-SM with PMIPv6
draft-asaeda-multimob-pmip6-extension-11
Abstract
This document describes IP multicast routing optimization using
PIM-SM in Proxy Mobile IPv6 (PMIPv6) environment. The Mobile Access
Gateway (MAG) and the Local Mobility Anchor (LMA) are the mobility
entities defined in the PMIPv6 protocol and act as PIM-SM routers.
The proposed protocol optimization addresses the tunnel convergence
problem and cooperates with seamless handover mechanisms.
Status of this Memo
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This Internet-Draft will expire on April 25, 2013.
Copyright Notice
Copyright (c) 2012 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
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include Simplified BSD License text as described in Section 4.e of
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the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Conventions and Terminology . . . . . . . . . . . . . . . . . 4
3. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3.1. Multicast Communication in PMIPv6 . . . . . . . . . . . . 4
3.2. Protocol Sequence for Multicast Channel Subscription . . . 6
4. Multicast Tunnel (M-Tunnel) . . . . . . . . . . . . . . . . . 7
4.1. Packet Encapsulation . . . . . . . . . . . . . . . . . . . 7
4.2. M-Tunnels Connecting to Multiple PIM-SM Routers and
ECMP Routing . . . . . . . . . . . . . . . . . . . . . . . 9
5. Local Mobility Anchor Operation . . . . . . . . . . . . . . . 10
6. Mobile Access Gateway Operation . . . . . . . . . . . . . . . 11
7. Mobile Node Operation . . . . . . . . . . . . . . . . . . . . 11
8. Localized Multicast Routing . . . . . . . . . . . . . . . . . 12
9. Smooth Handover . . . . . . . . . . . . . . . . . . . . . . . 12
10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15
11. Security Considerations . . . . . . . . . . . . . . . . . . . 15
12. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 15
13. References . . . . . . . . . . . . . . . . . . . . . . . . . . 15
13.1. Normative References . . . . . . . . . . . . . . . . . . . 15
13.2. Informative References . . . . . . . . . . . . . . . . . . 16
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 16
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1. Introduction
Proxy Mobile IPv6 (PMIPv6) [1] enables network-based mobility for
IPv6 mobile nodes (MNs) that do not implement any mobility protocols.
The Local Mobility Anchor (LMA) is the topological anchor point to
manages the mobile node's binding state. The Mobile Access Gateway
(MAG) is an access router or gateway that manages the mobility-
related signaling for an MN. An MN is attached to the Proxy Mobile
IPv6 Domain (PMIPv6-Domain) that includes LMA and MAG(s), and is able
to receive data coming from outside of the PMIPv6-Domain through LMA
and MAG.
Network-based mobility support for unicast is addressed in [1], while
multicast support in PMIPv6 is not discussed in it. Since LMA and
MAG set up a bi-directional IPv6-in-IPv6 tunnel for each mobile node
and forwards all mobile node's traffic according to [1], it highly
wastes network resources when a large number of mobile nodes join/
subscribe the same multicast sessions/channels, because independent
data copies of the same multicast packet are delivered to the
subscriber nodes in a unicast manner through MAG.
The base solution described in [12] provides options for deploying
multicast listener functions in PMIPv6-Domains without modifying
mobility and multicast protocol standards. However, in this
specification, MAG MUST act as an MLD proxy [2] and hence MUST
dedicate a tunnel link between LMA and MAG to an upstream interface
for all multicast traffic. This limitation does not allow to use
PIM-SM native routing on MAG, and hence does not solve the tunnel
convergence problem; MAG receives the same data from multiple LMAs
when MAG attaches to them for mobile nodes and has subscribed the
same multicast channel to them. It does not enable direct routing
and does not optimize source mobility.
This document describes IP multicast routing optimization using
PIM-SM in Proxy Mobile IPv6 (PMIPv6) environment. The Mobile Access
Gateway (MAG) and the Local Mobility Anchor (LMA) are the mobility
entities defined in the PMIPv6 protocol and act as PIM-SM routers.
The proposed protocol optimization assumes that both LMA and MAG
enable the Protocol-Independent Multicast - Sparse Mode (PIM-SM)
multicast routing protocol [3]. The proposed optimization uses a
dedicated GRE [4] tunnel for multicast, called M-Tunnel between MAG
and PIM-SM router such as LMA. The proposed protocol optimization
addresses the tunnel convergence problem and provides seamless
handover. It can cooperate with localized routing and direct routing
to deliver IP multicast packets for mobile nodes and source mobility.
In this document, because multicast listener mobility is mainly
focused on, the detail specification of source mobility is not
described.
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This document does not require to change unicast communication
methods or protocols defined in [1], and therefore both unicast and
multicast communications for mobile nodes in PMIPv6-Domain are
enabled if this extension is implemented.
2. Conventions and 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 RFC 2119 [5].
The following terms used in this document are to be interpreted as
defined in the Proxy Mobile IPv6 specification [1]; Mobile Access
Gateway (MAG), Local Mobility Anchor (LMA), Mobile Node (MN), Proxy
Mobile IPv6 Domain (PMIPv6-Domain), LMA Address (LMAA), Proxy Care-of
Address (Proxy-CoA), Mobile Node's Home Network Prefix (MN-HNP),
Mobile Node Identifier (MN-Identifier), Proxy Binding Update (PBU),
and Proxy Binding Acknowledgement (PBA).
3. Overview
3.1. Multicast Communication in PMIPv6
Required components to enable IP multicast are multicast routing
protocols and host-and-router communication protocols. This document
assumes PIM-SM [3] as the multicast routing protocol and Multicast
Listener Discovery (MLD) as the host-and-router communication
protocol. This document allows mobile nodes to participate in Any-
Source Multicast (ASM) and Source-Specific Multicast (SSM) [6].
However, in order to explicitly participate in SSM, mobile nodes MUST
support either MLDv2 [7] or Lightweight-MLDv2 (LW-MLDv2) [8].
The architecture of a Proxy Mobile IPv6 domain is shown in Figure 1.
LMA and MAG are the core functional entities in PMIPv6-Domain. The
entire PMIPv6-Domain appears as a single link from the perspective of
each mobile node.
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+---------+
| Content |
| Source |
+---------+
|
*** *** *** *** ***
* ** ** ** ** *
* *
* Fixed Internet *
* *
* ** ** ** ** *
*** *** *** *** ***
/ \
+----+ +----+
|LMA1| |LMA2|
+----+ +----+
LMAA1 -> | | <-- LMAA2
| |
\\ //\\
\\ // \\
\\ // \\
\\ // \\
\\ // \\
\\ // \\
Proxy-CoA1--> | | <-- Proxy-CoA2
+----+ +----+
|MAG1|---{MN2} |MAG2|
+----+ | +----+
| | |
MN-HNP1 --> | MN-HNP2 | <-- MN-HNP3, MN-HNP4
{MN1} {MN3}
Figure 1: Proxy Mobile IPv6 Domain
When a mobile node wants to subscribe/unsubscribe a multicast
channel, it sends MLD Report messages specifying sender and multicast
addresses to the access link. The attached MAG detects this
membership information and sends the PIM Join/Prune message to the
corresponding LMA over a bi-directional GRE tunnel called M-Tunnel
(described in Section 4) when the LMA is selected as the previous-hop
router for the multicast channel, or sends the PIM Join/Prune message
to the adjacent upstream multicast router for the multicast channel.
When the LMA or the adjacent router receives the PIM Join/Prune
message, it coordinates the corresponding multicast routing tree if
necessary and starts forwarding the data.
When the MAG detects mobile node's handover, it can proceed the
seamless handover procedures. Since both PMIPv6 and multicast
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protocols (i.e., MLD and PIM-SM) do not have functions for multicast
context transfer in their original protocol specifications, the
external functions or protocols should be used for handover. One of
the possibile ways is the use of "mobile node's Policy Profile", as
it could include "multicast channel information", which expresses
mobile node's subscribing multicast channel list, as well as the
mandatory fields of the Policy Profile specified in [1]. Mobile
node's Policy Profile is provided by "policy store" whose definition
is the same as of [1].
3.2. Protocol Sequence for Multicast Channel Subscription
A mobile node sends unsolicited MLD Report messages including source
and multicast addresses when it subscribes a multicast channel.
Although MLDv2 specification [7] permits to use the unspecified
address (::) for a host whose interface has not acquired a valid
link-local address yet, MAG SHOULD send MLDv2 Report messages with a
valid IPv6 link-local source address as defined in [13]. As well,
MLDv2 Report messages MAY be sent with an IP destination address of
FF02:0:0:0:0:0:0:16, to which all MLDv2-capable multicast routers
listen, but the IP unicast address of the attached MAG SHALL be used
for the destination of MLDv2 Report messages.
When the MAG operating as a PIM-SM router receives MLD Report
messages from attached mobile nodes, it joins the multicast delivery
tree by sending PIM Join messages to its neighboring routers
(Figure 2). When the upstream router for the requested channel is
LMA, the MAG sends the corresponding PIM Join messages to the LMA
using M-Tunnel (described in Section 4), if the MAG has not joined to
the requested multicast channel. When the upstream router for the
requested channel is an adjacent router that is not the LMA, the MAG
sends the corresponding PIM Join messages to the adjacent upstream
router natively, if the MAG has not joined to the requested multicast
channel. The LMA or the adjacent upstream router then joins the
multicast delivery tree and forwards the packets to the downstream
MAG.
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MN1 MN2 MAG LMA
| | | |
|------MLD Report--------->| |
| (S1,G1) join | PIM (S1,G1) Join |
| | |===== M-Tunnel ===>|
| | | |---> PIM (S1,G1) Join
| | | |
| |--MLD Report-->| |
| | (S2,G2) join | |
| | |---> PIM (S2,G2) Join
| | | |
| |--MLD Report-->| |
| | (S1,G1) join | |
| | | |
Figure 2: MLD Report and PIM Messages Transmission
The MAG selects only one upstream interface (either M-Tunnel
interface or physical interface) for a multicast channel by the
Reverse Path Forwarding (RPF) algorithm. This does not cause the
tunnel convergence problem, because Multicast Routing Information
Base (MRIB) used by PIM-SM selects only one upstream interface for
each multicast channel and hence duplicate packets are not forwarded
to the MAG.
4. Multicast Tunnel (M-Tunnel)
4.1. Packet Encapsulation
M-Tunnel is a bi-directional GRE tunnel [4] dedicated for PIM
messages and IP multicast data transmissions. The tunnel end-point
of M-Tunnel is a MAG that is a PIM-SM capable router. Another tunnel
end-point is also a PIM-SM capable router. The typical use case of
M-Tunnel is to establish a bi-directional tunnel link between LMA and
MAG; therefore LMA shall be another tunnel end-point. M-Tunnel can
be established in a bootstrap phase of MAG (without detecting a
multicast channel subscription request from a mobile node) and kept
while the MAG enables PIM routing functions to forward multicast
packets. An M-Tunnel is not set up per mobile node basis, but per
MAG basis; it can be shared with mobile nodes attached to the MAG as
seen in Figure 3.
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MC1
\
\-->
MC2---->LMA===MC1,MC2 for MNs====>MAG
MC: Multicast packets, ==>: M-Tunnel
Figure 3: Multicast packet forwarding through M-Tunnel
In order for the PIM routing protocol to use an M-Tunnel for
multicast forwarding, an M-Tunnel interface must be recognized by the
PIM routing protocol as the upstream multicast interface for MAG. It
is done by the configuration of static multicast routes, such as "ip
mroute 0.0.0.0 0.0.0.0 gre0" or "ip mroute 1.1.1.0 255.255.255.0
gre0". By such configuration, MAG inserts the multicast route paths
using the M-Tunnel into its MRIB. MAG then selects the M-Tunnel
interface as the corresponding RPF interface, and forwards the PIM
Join/Prune messages over the M-Tunnel. If operators want to select
other interface, e.g. a physical interface, as the upstream multicast
interface for some specific source prefixes, e.g. sources inside the
PMIPv6-Domain, they can *additionally* configure the specific
multicast routes with longer prefixes. This configuration will be
used for direct routing. Then the MAG selects as the appropriate
upstream router according to the MRIB entry. Note that the case
having multiple M-Tunnels configured on MAG is described in
Section 4.2.
The format of the tunneled multicast packet forwarded from LMA to MAG
is shown below. "S" and "G" are the same notation used for (S,G)
multicast channel.
IPv6 header (src= LMAA, dst= Proxy-CoA) /* Outer Header */
GRE header /* Encapsulation Header */
IPv6 header (src= S, dst= G) /* Inner Header */
Upper layer protocols /* Packet Content */
Figure 4: Multicast packet format tunneled from LMA to MAG
When a PIM message is sent from MAG to LMA, the src and dst addresses
of the outer tunnel header will be replaced to Proxy-CoA and LMAA,
respectively. To convey a PIM message, the src address of the inner
packet header is changed to either LMA's or MAG's link-local address.
The dst address of the packet header is assigned based on the PIM's
condition (see [3]).
In order to establish M-Tunnel, LMA and MAG need to negotiate GRE
encapsulation and GRE keys for M-Tunnel. The GRE Key option to be
used for the negotiation of GRE tunnel encapsulation mode and
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exchange of the uplink and downlink GRE keys is defined in [9]. It
is also possible to use the static fixed GRE keys for M-Tunnel.
4.2. M-Tunnels Connecting to Multiple PIM-SM Routers and ECMP Routing
There can be multiple LMAs in a PMIPv6-Domain each serving a
different group of mobile nodes. In that case, a MAG will connect to
multiple LMAs with different M-Tunnels having different GRE keys.
For example, in Figure 5, MAG1 establishes two M-Tunnels with LMA1
and LMA2, and MAG2 establishes one M-Tunnel with LMA2.
A MAG that has multiple M-Tunnels, such as MAG1 in Figure 5, must
decide a single upstream M-Tunnel interface for an RP or a source
address or prefix. There are two ways to decide a single upstream
M-Tunnel for a MAG. One is only with static MRIB configuration by
operation. For example, operators can configure each M-Tunnel
interface as the RPF interface for specific source adddress(es) or
prefix(es) one by one. Each M-Tunnel interface is then inserted into
the MAG's MRIB and used for different source adddress(es) or
prefix(es).
The other way to select a single upstream M-Tunnel interface is with
PIM ECMP [14]. A MAG enabling PIM routing functions selects a path
in the ECMP based on its own implementation specific choice, which
may refer to the description in [14]. The PIM ECMP function chooses
the PIM neighbor with the highest IP address, or picks the PIM
neighbor with the best hash value over the destination and source
addresses. When operators decide to use PIM ECMP to select a single
upstream M-Tunnel from multiple M-Tunnels, both MAG and the tunnel
end-point PIM-SM routers (e.g., LMAs) MUST enable PIM ECMP.
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+----+ +----+
|LMA1| |LMA2|
+----+ +----+
|| || ||
|| || ||
\\ M-Tunnel // \\
\\ | // \\
\\ +-> // \\ <-- M-Tunnel
M-Tunnel ---> \\ // \\
(encapsulating \\ // \\
with GRE header) \\ // \\
|| || ||
+----+ +----+
|MAG1|---{MN2} |MAG2|
+----+ +----+
| |
| |
{MN1} {MN3}
Figure 5: M-Tunnels established between LMA and MAG
5. Local Mobility Anchor Operation
The LMA 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). This document assumes that the LMA is capable of
forwarding multicast packets to the MAG by enabling the Protocol-
Independent Multicast - Sparse Mode (PIM-SM) multicast routing
protocol [3]. The LMA acting as a PIM-SM multicast router may serve
MAGs as downstream routers for some multicast channels when a mobile
node is a multicast data receiver (or as upstream routers when a
mobile node is a multicast data sender). The downstream (or
upstream) MAG is connected to the LMA through the M-Tunnel for
multicast communication.
When the LMA sets up the multicast state and joins the group as the
MAG's upstream router, the multicast packets are tunneled to the MAG
that requested to receive the corresponding multicast session. The
MAG then forwards the packets to the mobile node according to the
multicast listener state maintained in the MAG. [1] supports only
point-to-point access link types for MAG and mobile node connection;
hence a mobile node and the MAG are the only two nodes on an access
link, where the link is assumed to be multicast capable.
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6. Mobile Access Gateway Operation
The MAG is the entity that performs the mobility management on behalf
of a mobile node. This document assumes that the MAG is PIM-SM
capable and forwards multicast packets to the corresponding mobile
nodes attached to MAG by enabling the PIM-SM multicast routing
protocol. In addition, the MAG must maintain multicast membership
status for the attached mobile nodes at the edge and forwards the
multicast data to the member mobile nodes. This condition requires
MAG to support MLDv2 [7] or LW-MLDv2 [8], as well.
When mobile nodes subscribe multicast channel(s), they send MLD
Report messages with their link-local address to the MAG, and the MAG
sends the corresponding PIM Join messages to the upstream router if
the MAG has no multicast state for the requested channel(s). The
upstream router is selected by the Reverse Path Forwarding (RPF)
lookup algorithm, and that is either the LMA or an adjacent multicast
router attached to the same link. If the LMA is the upstream router
for the channel(s) for the MAG, the MAG encapsulates PIM Join
messages using the M-Tunnel.
The MAG also sends MLD Query messages to attached mobile nodes to
maintain up-to-date membership states. Since the MAG may deal with a
large number of the downstream mobile nodes, the MLD protocol
scalability should be taken into account as described in [13].
Therefore it is RECOMMENDED that the explicit tracking function [15]
is enabled on the MAG.
The optimal multicast routing path may not include the LMA,
especially in localized routing as described in Section 6.10.3 of [1]
and [10]. The localized routing option is designed to support node-
to-node communication within PMIPv6-Domain where a local content
source exists. Details are described in Section 8.
7. Mobile Node Operation
Mobile nodes attached to the MAG can behave as regular receiver
hosts. A mobile node sends MLD report messages to the MAG when it
wants to subscribe and unsubscribe IP multicast channels.
In order to subscribe/unsubscribe multicast channel(s) by unsolicited
report messages and inform current membersip state by solicited
report messages, mobile nodes MUST support either MLDv1 [7], MLDv2
[7], or LW-MLDv2 [8], and SHOULD support MLDv2 or LW-MLDv2.
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8. Localized Multicast Routing
Localized routing defined in [10] allows mobile nodes attached to the
same or different MAGs to directly exchange unicast traffic by using
localized forwarding or a direct tunnel between the MAGs. Localized
routing must be initiated both MAG and LMA. Localized routing is not
persistent, and is initiated by two signaling messages, Localized
Routing Initiation (LRI) and Local Routing Acknowledgment (LRA), sent
by LMA or MAG.
To support localized multicast routing with PIM-SM capable LMA and
MAG, both LMA and MAG MUST include the routes orgzanized by the
localized routing procedure specified in [10] into their MRIBs. The
exact mechanism to do this is not specified in this document and is
left open for implementations and specific deployments.
To support localized routing for the case that a source node and a
receiver node are attached to different MAGs but the same LMA (as
seen in Section 6 of [10]), these MAGs must use the same tunneling
mechanism for the data traffic tunneled between them. M-Tunnel
defined in this document corresponds to the concept; these MAGs
establish M-Tunnel and enable localized multicast routing.
9. Smooth Handover
The MAG is responsible for detecting the mobile node's movements to
and from the access link and for initiating binding registrations to
the mobile node's LMA. In PMIPv6, it does not require for mobile
nodes to initiate to re-subscribe multicast channels, and the MAG
keeps multicast channel subscription status for mobile nodes even if
they move to a different MAG (i.e., n-MAG) in PMIPv6-Domain.
The MAG needs to join the multicast delivery tree when an attached
mobile node subscribes a multicast channel. When the mobile node
changes the network, it seamlessly receives multicast data from the
new MAG according to the multicast channel information stored in the
"MN's Policy Profile" or by some handover mechanisms such as [16] and
[17]. Whether the MN's Policy Profile or a hondover mechanism mobile
operators use depend on their policy or implementation.
Here, a handover procedure using the MN's Policy Profile is described
as an example. When the multicast channel information subscribed by
mobile nodes is maintained in "MN's Policy Profile" stored in a
policy store [1], the MAG can use the channel information to provide
seamless handover. The procedures are described as follows and
illustrated in Figure 6;
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1. Figure 6 shows the examples that a mobile node has received
multicast data from an upstream multicast router via p-MAG (*1)
and from LMA via p-MAG (*2).
2. Whenever the mobile node moves a new network and attaches to
n-MAG, the n-MAG obtains the MN-Identifier (MN-ID) and learns
multicast channel information described in Mobile Node's Policy
Profile associated to this MN-Identifier. Describing the method
how the n-MAG identifies the p-MAG is out of scope of this
document, while using the same mechanism described in [18] would
be one of the possible methods.
3. If there are multicast channels the mobile node has subscribed
but the n-MAG has not yet subscribed, n-MAG joins the
corresponding multicast channels by sending the PIM Join message
to its upstream router. If the upstream router is the LMA, the
PIM messages are encapsulated and transmitted over the M-Tunnel
(*4); otherwise the PIM messages are sent natively to the
adjacent upstream router (*3).
4. The multicast data is forwarded from the LMA through the
M-Tunnel between the LMA and n-MAG (*4) or from the adjacent
upstream router (*3).
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MN p-MAG LMA n-MAG
| | | |
|--MLD Report->| | |
| |---> PIM Join (*1) |
| | PIM Join (*2) | |
| |==== M-Tunnel ====>| |
| | |---> PIM Join (*2)
| | | |
|<--Multicast--| | |
| data (*1) | | |
| |Multicast data (*2)| |
|<-------------|<=== M-Tunnel =====| |
| | | |
Detach | | |
| | | |
Attach | | |
| | | MN attachment event
| | | (Acquire MN-ID and Profile)
|-------------------------RS-------------------------->|
| | | |
| | |<-------PBU--------|
| | | |
| | |--------PBA------->|
| | | |---> PIM Join (*3)
| | | PIM Join (*4) |
| | |<==== M-Tunnel ====|
| | | |
|<------------------------RA---------------------------|
| | | |
| | Multicast data (*3) |
|<-----------------------------------------------------|
| | |Multicast data (*4)|
| | |==== M-Tunnel ====>|
|<-----------------------------------------------------|
| | | |
Figure 6: Handover with MN's Policy Profile
After MN attaches to n-MAG, the multicast data will be delivered to
the MN immediately. MN's multicast membership state is maintained
with MLD Query and Report messages exchanged by MN and n-MAG. If
p-MAG thinks that the moving mobile node is the last member of
multicast channel(s) (according to the membership record maintained
by the explicit tracking function [15]), p-MAG confirms it by sending
MLD query. After the confirmation, p-MAG leaves the channel(s) by
sending the PIM Prune message to its upstream router.
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10. IANA Considerations
This document has no actions for IANA.
11. Security Considerations
TBD.
12. Acknowledgements
Many of the specifications described in this document are discussed
and provided by the multimob mailing-list.
13. References
13.1. Normative References
[1] Gundavelli, S, Ed., Leung, K., Devarapalli, V., Chowdhury, K.,
and B. Patil, "Proxy Mobile IPv6", RFC 5213, August 2008.
[2] Fenner, B., He, H., Haberman, B., and H. Sandick, "Internet
Group Management Protocol (IGMP) / Multicast Listener Discovery
(MLD)-Based Multicast Forwarding ("IGMP/MLD Proxying")",
RFC 4605, August 2006.
[3] Fenner, B., Handley, M., Holbrook, H., and I. Kouvelas,
"Protocol Independent Multicast - Sparse Mode (PIM-SM):
Protocol Specification (Revised)", RFC 4601, August 2006.
[4] Farinacci, D., Li, T., Hanks, S., Meyer, D., and P. Traina,
"Generic Routing Encapsulation (GRE)", RFC 2784, March 2000.
[5] Bradner, S., "Key words for use in RFCs to indicate requirement
levels", RFC 2119, March 1997.
[6] Holbrook, H. and B. Cain, "Source-Specific Multicast for IP",
RFC 4607, August 2006.
[7] Vida, R. and L. Costa, "Multicast Listener Discovery Version 2
(MLDv2) for IPv6", RFC 3810, June 2004.
[8] Liu, H., Cao, W., and H. Asaeda, "Lightweight Internet Group
Management Protocol Version 3 (IGMPv3) and Multicast Listener
Discovery Version 2 (MLDv2) Protocols", RFC 5790,
February 2010.
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[9] Muhanna, A., Khalil, M., Gundavelli, S., and K. Leung, "Generic
Routing Encapsulation (GRE) Key Option for Proxy Mobile IPv6",
RFC 5845, June 2010.
[10] Krishnan, S., Koodli, R., Loureiro, P., Wu, Q., and A. Dutta,
"Localized Routing for Proxy Mobile IPv6", RFC 6705,
September 2012.
[11] Deering, S., Fenner, W., and B. Haberman, "Multicast Listener
Discovery (MLD) for IPv6", RFC 2710, October 1999.
13.2. Informative References
[12] Schmidt, T., Waehlisch, M., and S. Krishnan, "Base Deployment
for Multicast Listener Support in Proxy Mobile IPv6 (PMIPv6)
Domains", RFC 6224, April 2011.
[13] Asaeda, H., Liu, H., and Q. Wu, "Tuning the Behavior of the
Internet Group Management Protocol (IGMP) and Multicast
Listener Discovery (MLD) for Routers in Mobile and Wireless
Networks", RFC 6636, May 2012.
[14] Thaler, D. and C. Hopps, "Multipath Issues in Unicast and
Multicast Next-Hop Selection", RFC 2991, November 2000.
[15] Asaeda, H. and N. Leymann, "IGMP/MLD-Based Explicit Membership
Tracking Function for Multicast Routers",
draft-ietf-pim-explicit-tracking-02.txt (work in progress),
October 2012.
[16] Contreras, LM., Bernardos, CJ., and I. Soto, "PMIPv6 multicast
handover optimization by the Subscription Information
Acquisition through the LMA (SIAL)",
draft-ietf-multimob-fast-handover-01.txt (work in progress),
July 2012.
[17] von Hugo, D. and H. Asaeda, "Context Transfer Protocol
Extension for Multicast",
draft-vonhugo-multimob-cxtp-extension-02.txt (work in
progress), August 2012.
[18] Yokota, H., Chowdhury, K., Koodli, R., Patil, B., and F. Xia,
"Fast Handovers for Proxy Mobile IPv6", RFC 5949,
September 2010.
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Authors' Addresses
Hitoshi Asaeda
National Institute of Information and Communications Technology
4-2-1 Nukui-Kitamachi
Koganei, Tokyo 184-8795
Japan
Email: asaeda@nict.go.jp
Pierrick Seite
France Telecom
4, rue du Clos Courtel
BP 91226, Cesson-Sevigne 35512
France
Email: pierrick.seite@orange-ftgroup.com
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