Internet DRAFT - draft-sfigueiredo-multimob-use-case-dmm
draft-sfigueiredo-multimob-use-case-dmm
MULTIMOB Group S. Figueiredo
Internet Draft Universidade de Aveiro
Intended status: Informational S. Jeon
Expires: April 22, 2013 Instituto de Telecomunicacoes
R. L. Aguiar
Universidade de Aveiro
October 22, 2012
IP Multicast Use Cases and Analysis over Distributed Mobility
Management
draft-sfigueiredo-multimob-use-case-dmm-03.txt
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Abstract
Mobile networks are changing towards distributed mobility management
(DMM), tackling inefficiencies of existing mobility protocols
regarding network management and packet routing. Identifying IP
multicast use cases applicable to DMM is a logical step before
exploring solution spaces. This document describes use cases where IP
multicast is applied in DMM environments, considering two main
deployment options: multicast router or MLD-Proxy deployment at a
Mobility Access Router (MAR). Due to the lack of standard terminology,
we refer to MAR as the entity embedding mobility-related functions,
e.g. providing network access and flow anchoring capabilities. Each
deployment option is thoroughly analyzed regarding its advantages and
disadvantages, and both multicast listener and source mobility
support are considered.
Table of Contents
1. Introduction...................................................3
2. Conventions and Terminology....................................3
3. Use Cases Description..........................................4
3.1. Assumptions...............................................4
3.2. Mobile Multicast listener.................................5
3.2.1. MLD Proxy deployment at MAR..........................5
3.2.1.1. Operation.......................................5
3.2.1.2. Detailed analysis...............................6
3.2.2. Multicast Router deployment at MAR...................8
3.2.2.1. Operation.......................................8
3.2.2.2. Detailed analysis...............................8
3.3. Multicast sender support..................................9
3.3.1. MLD Proxy deployment at MAR..........................9
3.3.1.1. Operation.......................................9
3.3.1.2. Detailed analysis..............................10
3.3.2. Multicast Router deployment at MAR..................14
3.3.2.1. Operation......................................14
3.3.2.2. Detailed analysis..............................14
3.4. Summary of analysis......................................15
4. IANA Considerations...........................................16
5. Security Considerations.......................................16
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6. References....................................................17
6.1. Normative References.....................................17
6.2. Informative References...................................17
1. Introduction
Centralized mobility management approach brings several drawbacks
such as non-optimal routing or severe overloading on the anchor point.
Such problems are expected to be more severe as mobile devices data
consumption (and generation) increases.
In order to tackle these problems, the concept of distributed
mobility management (DMM) has emerged. It couples per flow and
distributed anchoring, bringing the mobility anchor closer to the MN.
IP multicast, as one of the enablers for efficient distribution of
multimedia content, is composed of two main functions: multicast
routing and membership subscription. When those are coupled with IP
mobility, it is very critical to know possible use cases and
respective issues, since those techniques were mainly designed for
fixed networks.
This document presents possible use cases of IP multicast in a DMM
environment, by aligning to DMM Requirements [DMMREQ]. The different
use cases result from the different functionalities provided at the
MAR - MLD Proxy or MR -, and both mobile listener and sender support
are analyzed. The goal was to identify the advantages (e.g. ease of
deployment, resource-lightness) and constrains (e.g. lack of resource
efficiency, non-optimal routing) of each deployment option,
considering its impact for the support of mobile sender or mobile
listeners.
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 [RFC2119].
This document uses the terminology defined in [RFC5213], [RFC6275],
and [RFC3810], and [RFC4601]. Also, new entities are defined relying
on the PMIPv6 entities specified in [RFC5213]:
- Mobility Access Router (MAR): A router with the capability of
acting both as a mobility anchor and as an access router, in a per
flow basis. It can act as either a P-MAR, a N-MAR, or both.
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- Previous Mobility Access Router (P-MAR): The MAR where the MN was
attached to previously to the IP mobility event, and which is
acting as an anchor for one or multiple flows.
- New Mobility Access Router (N-MAR): The MAR to which the MN is
currently attached. It provides the network access and thus
delivers all the flows destined to the MN's HNPs - including those
anchored to previously visited P-MARs.
- Multicast Listener Discovery Proxy (MLD-P): An entity providing
MLD based forwarding following the operation defined in [RFC4605].
In the current document, only MLDv2-based signaling is considered,
targeting IPv6 networks (REQ3 from [DMMREQ]).
3. Use Cases Description
We identify different use cases that result from the application of
existing standards for IP multicast support over mobile environments.
We first consider mobile multicast listeners and then mobile
multicast senders, and for each case we analyze the impact of
deploying distinct functionality at the MAR: either MLD Proxy or
Multicast Router (namely PIM-SM capability).
3.1. Assumptions
A1: This draft refers to the requirements in [DMMREQ] as the base DMM
framework.
A2: Network access and data anchor functionalities are based in
[RFC5213], and are assumed to be provided by a Mobility Access Router
(MAR).
A3: It is assumed that when the IP mobility happens, at least one
multicast flow is being received (listener) / sent (sender). and a
mobility tunnel will be created between the P-MAR and the N-MAR.
A4: Using MLD Proxy, and when a user without mobility session starts
a multicast session at a MAR, the upstream interface of MLD Proxy is
configured towards an upstream multicast router in the multicast
infrastructure. But when a user moves to another MAR (N-MAR), under
assumption A3, the upstream interface of MLD Proxy will be configured
towards the anchor that enables unicast IP address continuity to be
kept (P-MAR, analogous to LMA function).
A5: Mobility occurs within a single PIM-SM multicast routing domain.
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3.2. Mobile Multicast listener
3.2.1. MLD Proxy deployment at MAR
3.2.1.1. Operation
In this use case, MLD Proxy is considered as being deployed at all
MARs, and operating in an analogous way to the Base Multicast support
solution for PMIPv6 [RFC4605]. As such, after mobility, the upstream
interface MUST be configured towards the mobility tunnel endpoint,
i.e., P-MAR.
When a MN initially attaches to the P-MAR (as shown in Figure 1), it
receives a HNP address which will be associated with communications
started at that MAR. As the P-MAR detects the new logical link, it
transmits a General MLD Query message to which the MN will not yet
reply, as it is not yet running any multicast session. The P-MAR then
adds the downstream logical link to the MLD Proxy instance [RFC4605].
In this case, i.e. when users subscribe to multicast content only
after associating with the MAR, the MLD Proxy will set its uplink to
the multicast infrastructure. When the MN intends to start receiving
the multicast session, it will send an unsolicited MLD Report,
triggered by its application. On receiving the latter message, the
MLD Proxy tries to join the multicast channel(s) by sending an
aggregated MLD Report through the MLD Proxy upstream interface. Note
that the same MLD Proxy instance will be assigned to all MNs which
initiated their multicast subscriptions in the current MAR (i.e. the
MNs having no multicast mobility session). When the joining procedure
ends, multicast data is transmitted through the same interfaces,
until reaching the MN.
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+----------------+
| Multicast |
| Infrastructure |
+----------------+
*
* (S,G)
*
+----------+ +----------+
| P-MAR |---------------| N-MAR |
| |***************| |
| (MLD-P) |---------------| (MLD-P) |
+----------+ +----------+
* *
* *
+------+ +------+
| MN | -----> | MN |
+------+ +------+
Figure 1 Multicasting architecture using distributed mobility
management
When the MN moves from P-MAR, the N-MAR is required to establish a
tunnel for IP session continuity of the flows being sent towards and
from the MN's HNP assigned by the P-MAR. This implies that N-MAR has
an appropriate method to know the P-MAR. Multiple ideas are supposed
to be made at the solution stage of DMM WG, therefore it is out of
scope of this document. Following the operation of the MLD Proxy
[RFC4605], after the bidirectional tunnel establishment, the
following process takes place. First, the N-MAR sends a General MLD
Query, and verifies whether the MN is admissible for multicast
sessions. Then, the MLD Proxy at the N-MAR adds the downstream
interface corresponding to the MN, and configures the upstream
interface towards the MN's P-MAR, i.e. the tunnel endpoint.
3.2.1.2. Detailed analysis
This scheme is simple and directly applicable to a network-based
multicast DMM approach, as no extensions for multicast-related
operation are required. Besides, the MLDv2 Proxy was devised with a
less resource-demanding nature compared to MRs, aimed for scenarios
where multicast routing is not beneficial or required. The same
applies in DMM scenarios. However, this approach leads to a couple of
relevant issues. Traffic duplication is the result of the tunnel
convergence problem, occurring e.g. in [RFC6224]. As shown in Figure
2, MN1 and MN3, which moved from MAR1 and MAR3, respectively, are
currently located at the MAR2. Through their respective tunnels, they
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receive multicast packets of the same channel through different
anchoring MARs. This causes duplicated traffic to converge to the
MAR2. Concretely, the magnitude of replicated traffic is expected to
be much higher than that of PMIPv6, considering the consequences of
having a single mobility entity coupling anchoring and network access
provision: we assume that the number of MARs in future DMM domains
will be much larger than that of LMAs at core level within a PMIPv6
domain.
+----------------+
| Multicast Tree | *
+----------------+ *
* * *
* * *
* * *
(S,G) * (S,G) * * (S,G)
* * *
+----------+ (-->) +----------+ (<--) +----------+
| MAR1 |---------| MAR2 |---------| MAR3 |
| |*********| |*********| |
| (MLD-P) |---------| (MLD-P) |---------| (MLD-P) |
+----------+ Tun.1 +----------+ Tun.2 +----------+
* * *
* * *
* * *
+---+ move +---+ +---+ +---+ move +---+
|MN1| ---> |MN1| |MN2| |MN3| <--- |MN3|
+---+ +---+ +---+ +---+ +---+
(<--/-->) : direction of the multicast packet flow
Figure 2 Data replication
Another issue is non-optimal routing (Figure 3). If we consider a
significantly large domain, multicast packets may traverse a long
distance, depending on the setup direction of the upstream interface
of MLD Proxy instances. The issue is more noticeable if we assume all
MARs are connected to the multicast infrastructure.
When MLD Proxy is used in mobile multicast, low performance handover
will result from the need of going through the following process: 1)
MLD Proxy sets up the new MLD interface, 2) MLD Proxy sends the
General MLD Query, 3) MN sends the MLD Report. Only then MN will
receive the content, which for a significant number of IP multicast-
based applications, will represent a noticeable service disruption.
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+----------------+
| Multicast |
| Infrastructure |
+----------------+
*
* (S,G)
*
+----------+ +----------+
| P-MAR |------ ------| N-MAR |
| |****** ... ******| |
|(MLD-P) |------ ------| (MLD-P) |
+----------+ +----------+
* *
* *
+------+ +------+
| MN | -----> | MN |
+------+ +------+
Figure 3 Non-optimal routing problem
3.2.2. Multicast Router deployment at MAR
3.2.2.1. Operation
In this use case, PIM-SM is deployed at all MARs. After the MN
attaches to a MAR, its PIM instance will act as the Designated Router
(DR) for the MN (and all other attached nodes). The procedure for
multicast subscription will be the same as in a fixed network, i.e.
the MN sends the Explicit MLD Report, and the MR at the MAR will
process that message and join any multicast channel if needed.
When the MN moves, the mobility tunnel will be setup between the two
MARs. As soon as the MN sends a MLD Report to the N-MAR, N-MAR will
join the multicast group / channel (if needed), the traffic will
start flowing from the tunnel and a new downstream state will be
configured.
3.2.2.2. Detailed analysis
An advantage of using MRs within MARs, is that multicast routing is
not affected due to RPF check. which leads to the selection of a
single upstream interface per MAR. This selection is independent of
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the number of existing mobility tunnels. On the other hand, the usage
of MLD Proxy might lead to the tunneling of the same multicast group
to a common MAR, and might mean severe replication, similarly to
[RFC6224].
As referred, although the mobility tunnel is activated after the MN
mobility, N-MAR will only subscribe the required multicast group /
channel after receiving the explicit MLD Report This can translate
into several lost packets, as the MN isn't aware of the mobility
process, and the General MLD Queries sent by MRs are periodic with a
varying frequency in the order of several seconds. Summarizing,
smooth handover cannot be assured without extending existing
mechanisms. When a MN moves to its N-MAR, there is the possibility
that the multicast channel(s) is (are) already being distributed
there. In such case, the new MAR will directly forward the multicast
traffic to the MN without using the tunnel for subscription function.
However, different MARs might be receiving common channels at
distinct times, which from the point of view from the receiver, will
result in frames replay (if receiving the same frames again) or miss
(in case the new MAR transmission is more advanced in time).
A possible non-efficiency is the unnecessary tunnel creation.
Following assumption A3, the tunnel is created due to the existence
of at least an ongoing multicast flow. The tunnel is created
independently of N-MAR's awareness to multicast subscriptions,
because the MLD Query occurs after its creation. Although, if the
subscription(s) of interest is (are) already being subscribed at the
N-MAR's MR, the tunnel will not be used at all for the multicast
subscription transmission. Thus, large scale creation of unnecessary
tunnels represents non-negligible wasted processing overhead.
3.3. Multicast sender support
3.3.1. MLD Proxy deployment at MAR
3.3.1.1. Operation
Sender mobility support is known to lead to service disruption
problems impacting all multicast tree, in particular if SPT is active.
In [SENDER], the utilization of MLD Proxy is proposed, being the
upstream interface always configured towards the fixed anchoring
entity - the LMA. To allow the sender to transmit multicast content
to the multicast tree in a DMM framework, the MLD Proxy should
configure its upstream interface towards a multicast router [PM-HOME].
Depending on the network topology, it may also be configured towards
a MLD Proxy placed on a neighbor MAR. On the multicast source's
mobility (Figure 4), an identical operation to the listener mobility
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case is expected from the MLD Proxy behavior. In this case, the
source uploads multicast traffic through one of MLD Proxy's
downstream interfaces, and the traffic is forwarded through the
uplink interface towards the P-MAR.
+------+ +----------------+
| RP |---------| Multicast |
+------+ | Infrastructure |
* +----------------+
* (S,G) |
* |
+----------+ +----------+
| P-MAR |----------| N-MAR |
| |**********| |
| (MLD-P) |----------| (MLD-P) |
+----------+ +----------+
* *
* *
+------+ +------+
| S | ----> | S |
+------+ +------+
Figure 4 Multicast sender mobility
3.3.1.2. Detailed analysis
The utilization of MLD Proxy carries the previously referred
advantages, as ease of deployment and operation lightness.
When a source moves to N-MAR from P-MAR, multicast data will be sent
through the mobility tunnel between N-MAR and P-MAR (Figure 5). If a
listener (L1) attaches to the same MAR (N-MAR), it will receive the
multicast data through multicast infrastructure, following the
configuration of MLD Proxy. Hence, the multicast data is routed non-
optimally between the source and the listener, going from N-MAR to P-
MAR, to the multicast routing tree, and then back to N-MAR again
before reaching the listener.
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+------+ +----------------+
| RP |*********| Multicast |
+------+ | Infrastructure |
* +----------------+
* (S,G) *
* *
+----------+ +----------+
| P-MAR |-------| N-MAR |
| |*******| |
| (MLD-P) |-------| (MLD-P) |
+----------+ +----------+
* * *
* * *
+------+ move +------+ +-----+
| S | ---> | S | | L1 |
+------+ +------+ +-----+
Figure 5 Triangular routing after source mobility
A similar problem occurs in the opposite process, i.e. if a multicast
source starts transmitting multicast content at a MAR, and a listener
moves to the same MAR while receiving the source's content (Figure
6).
+------+ +----------------+
| RP |*********| Multicast |
+------+ | Infrastructure |
* +----------------+
* (S,G) *
* *
+----------+ +----------+
| N-MAR |-------| P-MAR |
| |*******| |
| (MLD-P) |-------| (MLD-P) |
+----------+ +----------+
* * *
* * *
+------+ +----+ move +----+
| S | | L1 | <--- | L1 |
+------+ +----+ +----+
Figure 6 Triangular routing after listener mobility (MLD-Proxy case)
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When the source and the listener are within a same MAR (MAR2), if
both the source and listener try to send the session and receive it,
respectively, the traffic will be optimally sent to the listener
without going through native multicast infrastructure. As the traffic
reaches the MLD Proxy via the downstream interface to which the
source is attached, it will be sent through the downstream interface
to which the listener sent the MLD Report. However, if the source and
the listener move to different MARs, the traffic will traverse the
following non-optimal path, even though they share a common anchor:
Source -> MAR1 -> MAR2 -> Multicast Tree -> MAR2 -> MAR3
This problem is depicted in Figure 7.
+----------------+
| Multicast Tree |
+----------------+
* *
* *
* *
* *
* *
+----------+ (-->) +----------+ (-->) +----------+
| MAR1 |---------| MAR2 |---------| MAR3 |
| |*********| |*********| |
| (MLD-P) |---------| (MLD-P) |---------| (MLD-P) |
+----------+ Tun.1 +----------+ Tun.2 +----------+
* * * *
* * * *
* * * *
+---+ move +---+ +---+ move +---+
| S | <--- | S | | L | --> | L |
+---+ +---+ +---+ +---+
(<--/-->) : direction of the multicast packet flow
Figure 7 Multicast traffic non-optimal routing due to both mobile
sender and listener
REQ1 from [DMMREQ] refers that "DMM MUST enable a distributed
deployment of mobility management of IP sessions so that the traffic
can be routed in an optimal manner without traversing centrally
deployed mobility anchors". When a MN subscribes to a new multicast
session with existing multicast mobility session, the Aggregated MLD
Report containing all the MN's multicast subscriptions will be sent
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from the current MLD Proxy through the same uplink interface, i.e.
towards a single multicast mobility anchor. This results in some of
previously identified issues (e.g. non-optimality in the path that
both the subscription and multicast traffic traverse). It can be
stated that the MLD Proxy nature doesn't comply with the
aforementioned requirement, leading to the subscription of any
multicast flow using the same multicast mobility data path.
This problem is depicted in Figure 8, where both multicast flow 1 and
flow 2 reach MAR2 from MAR1, being flow 2's optimal routing path
affected by the mobility status of the MN, and in particular by the
order in which the multicast flows were subscribed. While this issue
is not exclusively related to mobile multicast sources, it is better
depicted and its' impact in the routing is more obvious when
considering one.
+----------------+
| Multicast Tree |
* +----------------+#
* #
* #
* #
* #
+----------+ (-->) +----------+
| MAR1 |--------- -------| MAR2 |
| |#*#*#*#*#............#*#*#*#| |
| (MLD-P) |--------- -------| (MLD-P) |
+----------+ Tunnel (used after mob.) +----------+
* * #
* downstream) # # (upstream)
* * #
* # #
+---+ move +---+ +---+
| L | ----------> | L | | S |
+---+ +---+ +---+
* : Multicast flow 1
# : Multicast flow 2 (subscribed after some time in MAR2)
Figure 8 Non-optimal routing due to single MLD Proxy uplink
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3.3.2. Multicast Router deployment at MAR
3.3.2.1. Operation
When a source starts transmitting multicast traffic, the content will
be encapsulated in PIM-Register messages, and sent towards the RP
(e.g .statically configured or discovered through a Bootstrapping
Router (BSR)). In DMM, the RP can be a core MR or a MAR (including
the initial MAR). The RP's SPT and each of the DR's SPTs may then be
created. When the source moves, N-MAR's MR will create the state for
the new multicast group, and the traffic will be forwarded using the
tunnel to the P-MAR, until reaching the RP (unless it is the PIM
instance at the P-MAR itself). It is then sent down the RPT. Again,
the creation of the SPTs will typically be triggered following PIM-SM
regular operation.
3.3.2.2. Detailed analysis
In case the RP's Source Path Tree is built before the mobility
process, it will be destroyed due to mobility, and the tree
construction process will be reinitiated at the new MAR. Also, in
case the Shortest Path Tree between the listener's DRs and the
sender's DR is being used, mobility will reset the PIM process to the
RPT stage. This means that each sender mobility event results in
increased signaling overhead and delay as consequence of the
multicast routing convergence (i.e. Phase 2 and Phase 3 from PIM-SM
operation). Moreover, non-optimal routing occurs when the RPT is used.
When a sender moves to a MAR where listeners are subscribing to the
channel it is sending, the multicast traffic will always reach the N-
MAR by going through the RP (as shown in Figure 9).
Using PIM-SM in DMM scenarios there is a trade-off between the
routing non-optimality of RPT and the non-efficient consequences of
frequent SPT establishment. It is important to note that this impact
is magnified the more listener's DRs are receiving the multicast
channel(s).
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+------+ +----------------+
| RP |*********| Multicast |
+------+ | Infrastructure |
* +----------------+
* (S,G) *
* *
+----------+ +----------+
| P-MAR |-------| N-MAR |
| |*******| |
| (MR) |-------| (MR) |
+----------+ +----------+
* * *
* * *
+------+ move +------+ +-----+
| S | ---> | S | | L1 |
+------+ +------+ +-----+
Figure 9 Triangular routing after source mobility (MR case)
3.4. Summary of analysis
Table I summarizes the previous analysis, globally depicting the
differences between MLD Proxy and MR over DMM. The relevant sections
for each feature are appended below, and the meaning of each feature
is extended afterwards.
===================================================================
| Feature \ Function | MLD Proxy | Multicast Router |
===================================================================
| Lightweight | Yes | No |
-------------------------------------------------------------------
| Optimal | No | Yes (using SPT) |
| routing |(3.2.1.2)/ (3.3.1.2) | (3.3.2.2) |
-------------------------------------------------------------------
| Efficient | No | Yes |
| distribution |(3.2.1.2)/ (3.3.1.2) | (3.2.2.2),(3.3.2.2) |
-------------------------------------------------------------------
| Distributed | No | Yes |
| anchoring | (3.3.1.2) | (3.2.2.2) |
-------------------------------------------------------------------
| Seamless mobility | No | No |
| (listener) | (3.2.1.2) | (3.2.2.2) |
-------------------------------------------------------------------
| HO signaling | Low | High (when using SPT)|
| overhead |(3.2.1.2), (3.3.1.2) | (3.3.2.2) |
-------------------------------------------------------------------
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| Tunnel is | Doesn't apply | No |
| always used | | (3.2.2.2) |
===================================================================
Table I. Comparison between MLD Proxy and MR deployment
The meaning of each of the entries is as follows:
Lightweight: this entry reflects whether the deployed multicast
feature has a resources-wise lightweight operation.
Optimal routing: This entry reflects whether optimal routing is
assured.
Efficient distribution: This entry reflects vulnerability to
multicast traffic replication.
Distributed anchoring: This entry assesses whether for a single MN,
different multicast streams can be anchored at different mobility
anchors or not.
Seamless mobility (listener): This entry reflects whether IP mobility
is seamless from the point of view of the mobile listener's
application.
HO signaling overhead: This entry assesses the amount of signaling
introduced by the IP mobility of a MN represents. This signaling may
be relative to the mobility protocol or the multicast routing
operation.
Tunnel is always used: This entry assesses whether the mobility
tunnel utilization is assured or not.
4. IANA Considerations
This document makes no request of IANA.
5. Security Considerations
TBD
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6. References
6.1. Normative References
[RFC2119] S. Bradner, "Key words for use in RFCs to Indicate
Requirement Levels", RFC 2119, March 1997.
[RFC6275] Johnson, D., Perkins, C., and J. Arkko, "Mobility Support
in IPv6", RFC 6275, July 2011.
[RFC3810] R. Vida, and L. Costa, "Multicast Listener Discovery
Version 2 (MLDv2) for IPv6," IETF RFC 3810, June 2004.
[RFC5213] S. Gundavelli, K. Leung, V. Devarapalli, K. Chowdhury, and
B. Patil, "Proxy Mobile IPv6", IETF RFC 5213, August 2008.
[RFC4605] B. Fenner, H. He, B. Haberman, and H. Sandick, "Internet
Group Management Protocol (IGMP) / Multicast Listener
Discovery (MLD) Based Multicast Forwarding ("IGMP/MLD
Proxying")", IETF RFC 4605, August 2006.
[RFC4601] B. Fenner, M. Handley, H. Holbrook, and I. Kouvelas,
"Protocol Independent Multicast - Sparse Mode (PIM-SM):
Protocol Specification (Revised)", RFC 4601, August 2006.
6.2. Informative References
[RFC6224] T. Schmidt, M. Waehlisch, S. Krishnan, "Base Deployment for
Multicast Listener Support in PMIPv6 Domain", RFC 6224,
April 2011.
[DMMREQ] H. Chan, "Requirements of distributed mobility management",
draft-ietf-dmm-requirements-02 (work in progress),
September 2012.
[SENDER] T C. Schmidt et al, "Mobile Multicast Sender Support in
Proxy Mobile IPv6 (PMIPv6) Domains", draft-ietf-multimob-
pmipv6-source-01 (work in progress), July 2012.
[PM-HOME] S. Jeon, N. Kang, and Y. Kim, "Mobility Management based on
Proxy Mobile IPv6 for Multicasting Services in Home
Networks," IEEE Transactions on Consumer Electronics (TCE),
vol. 55, no. 3, pp. 1227-1232, August 2009.
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Authors' Addresses
Sergio Figueiredo
Universidade de Aveiro
3810-193 Aveiro, Portugal
E-mail: sfigueiredo@av.it.pt
Seil Jeon
Instituto de Telecomunicacoes
Campus Universitario de Santiago
3810-193 Aveiro, Portugal
E-mail: seiljeon@av.it.pt
Rui L. Aguiar
Universidade de Aveiro
3810-193 Aveiro, Portugal
E-mail: ruilaa@ua.pt
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