MBONED Working Group H. Liu
Internet-Draft W. Cao
Expires: June, 2007 Huawei Technologies Co., Ltd.
H. Asaeda
Keio University
December 19, 2006
Lightweight IGMPv3 and MLDv2 Protocols
<draft-ietf-mboned-lightweight-igmpv3-mldv2-00.txt>
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Copyright Notice
Copyright (C) The Internet Society (2006).
Abstract
This document describes lightweight IGMPv3 and MLDv2 protocols (LW-
IGMPv3 and LW-MLDv2), which simplify the standard (full) versions of
IGMPv3 and MLDv2. The interoperability with the full versions and
the previous versions of IGMP and MLD is also taken into account.
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
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[KEYWORDS].
Table of Contents
1. Introduction ................................................... 2
2. Simplification Method Overview ................................. 4
2.1. Behavior of Group Members ................................. 4
2.2. Behavior of Multicast Routers ............................. 4
3. LW-IGMPv3 Protocol for Group Members ........................... 5
3.1. Action on Change of Interface State ....................... 5
3.2. Action on Reception of a Query ............................ 6
3.3. Applicable Group Record Types ............................. 7
4. LW-IGMPv3 Protocol for Multicast Routers ....................... 8
4.1. Group Timers and Source Timers
in the Lightweight Version ................................ 8
4.2. Source-Specific Forwarding Rules .......................... 9
4.3. Reception of Current-State Records ....................... 10
4.4. Reception of Source-List-Change and
Filter-Mode-Change Records ............................... 11
5. Interoperability .............................................. 12
5.1. Interoperation with the Full Version of IGMPv3 ........... 12
5.2. Interoperation with IGMPv1/IGMPv2 ........................ 13
5.2.1. Behavior of Group Members ........................... 13
5.2.2. Behavior of Multicast Routers ....................... 13
6. Implementation Considerations ................................. 13
6.1. Implementation of Source-Specific Multicast .............. 14
6.2. Implementation of Multicast Source Filter (MSF) APIs ..... 14
7. Security Considerations ....................................... 14
8. Normative References .......................................... 14
9. Informative References ........................................ 15
Intellectual Property Statement .................................. 16
Disclaimer of Validity ........................................... 16
Copyright Statement .............................................. 16
Acknowledgment ................................................... 16
1. Introduction
IGMP version 3 [IGMPv3] and MLD version 2 [MLDv2] implement source
filtering capability that is not suported by their earlier versions
IGMPv2 [IGMPv2] and MLDv1 [MLDv1]. An IGMPv3 or MLDv2 capable host
can tell which group it would like to join to its upstream router
with specifying which sources it does or does not intend to receive
multicast traffic from. IGMPv3 and MLDv2 add the capability for a
multicast router to also learn which sources are of interest to
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neighboring systems, for packets sent to any particular multicast
address.
The filter-modes are defined for the host and router parts of the
protocols respectively to support the source filtering function. If
a receiver host wants to receive from specific sources, it sends an
IGMPv3 or MLDv2 report with filter-mode set to INCLUDE. If the host
does not want to receive from some sources, it sends the report with
filter-mode set to EXCLUDE. A source list for the given sources
shall be included in the report message.
INCLUDE and EXCLUDE filter modes are also defined in a multicast
router to process the IGMPv3 or MLDv2 reports. When a multicast
router receives the report messages from its downstream hosts, it
forwards the corresponding multicast traffic by managing requested
group and source addresses. Group timer and source timer are used to
maintain forwarding state of desired group and source. A multicast
router decides its filter-mode, type, and value of the timers and
forwarding methods according to the specific rules when a group
report message arrives or the timer expires. The router then has to
switch its filter-mode under certain conditions. With all above
factors correlating with each other, the determination rule becomes
relatively complex as the interface states could be frequently
changed.
The multicast filter-mode improves the expressing ability of the
multicast receiver. It is useful to support Source-Specific
Multicast (SSM) [SSM] by specifying interesting source addresses with
INCLUDE mode. However, practical applications do not use EXCLUDE
mode to block sources so often, because a user or application usually
wants to specify desired source addresses, not undesired source
addresses to not receive from them. Even if a user wants to
explicitly refuse traffic from some sources in a group, when other
users in the same shared network have interest in these sources, the
corresponding multicast traffic is forwarded to the network after
all.
This document aims to propose the simplified IGMPv3 and MLDv2, being
named Lightweight IGMPv3 and Lightweight MLDv2 (or LW-IGMPv3 and LW-
MLDv2), in which EXCLUDE filter-mode that supports to exclude data
come from specified sources is eliminated. Not only LW-IGMPv3 and
LW-MLDv2 are compatible with the standard IGMPv3 and MLDv2, but also
the protocol operations made by data receiver hosts and routers or
switches (performing IGMPv3/MLDv2 snooping) are simplified in the
lightweight protocol and complicated operations are hence effectively
reduced. Since LW-IGMPv3 and LW-MLDv2 are fully compatible with the
full version of these protocols (i.e. the standard IGMPv3 and MLDv2),
hosts or routers that have implemented the full version do not need
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to implement or modify anything to cooperate with LW-IGMPv3/LW-MLDv2
hosts or routers.
2. Simplification Method Overview
The principle is to simplify the host and router parts as much as
possible to improve efficiency, while guaranteeing the
interoperability with the full versions, and introducing no side
effects on the applications.
For convenience, this document mainly discusses IGMPv3 since MLDv2
inherits the same source filtering mechanism, but additionally shows
MLDv2's unique specifications when needed.
2.1. Behavior of Group Members
In the LW-IGMPv3, the same service interface model as that of IGMPv3
is inherited:
IPMulticastListen ( socket, interface, multicast-address,
filter-mode, source-list )
In the lightweight protocol, EXCLUDE mode on the host part is
preserved only for EXCLUDE (*,G) join, which denotes non-source-
specific group report (as known as (*,G) join) and is equivalent to
the group membership join triggered by IGMPv2/IGMPv1/MLDv1. The
detailed host operation of LW-IGMPv3/LW-MLDv2 is described in section
3.
2.2. Behavior of Multicast Routers
According to [IGMPv3], router filter-mode is defined to optimize the
state description of a group. As a rule, once a member report is in
EXCLUDE mode, the router filter-mode for the group will be set to
EXCLUDE. When all systems cease sending EXCLUDE mode reports, the
filter-mode for that group may transit back to INCLUDE mode. Group
timer is used to identify such transition.
In LW-IGMPv3, member reports carry mainly the INCLUDE mode
information with only one exception for EXCLUDE (*,G), which means
including all sources and can also be interpreted as INCLUDE mode.
Without EXCLUDE mode report information, it is unnecessary for the
router to maintain the EXCLUDE filter-mode, and the state model for
multicast router can be simplified as:
(multicast address, group timer, (source records))
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Here group timer is kept to represent (*,G) group join. Its basic
behavior is: when a router receives a (*,G) group join, it will set
its group timer, and the source list for the source-specific group
will be kept. As the group timer expires, the router may change to
the reception for the listed sources.
The elimination of the filter-mode will greatly simplify the router
behavior, e.g. the action on reception of reports and the setting of
the timers. The detailed operation of router operation is described
in section 4.
3. LW-IGMPv3 Protocol for Group Members
LW-IGMPv3 uses two sets of messages, i.e., Query and Report messages,
being the same as the full version protocols. Although most of these
message types and corresponding group records are inherited from the
full version protocols, an operation that triggers EXCLUDE (S,G) join
is omitted and the corresponding record types of the Report are
modified on the lightweight protocols.
There are three Group Record Types defined in the full IGMPv3:
Current-State Record noted by MODE_IS_INCLUDE (referred to as IS_IN)
or MODE_IS_EXCLUDE (IS_EX), Filter-Mode-Change Record noted by
CHANGE_TO_INCLUDE_MODE (TO_IN) or CHANGE_TO_EXCLUDE_MODE (TO_EX), and
Source-List-Change Record noted by ALLOW_NEW_SOURCES (ALLOW) or
BLOCK_OLD_SOURCES (BLOCK).
3.1. Action on Change of Interface State
When an interface state of a group member host is changed, a State-
Change Report for that interface is immediately transmitted from that
interface. The type and contents of the Group Record(s) in that
Report are determined by comparing the filter mode and source list
for the affected multicast address before and after the change.
While the requirements are the same as the full version for the
computation, in the lightweight version host, the interface state
change rules are simplified due to the reduction of message types.
The contents of the new transmitted report are calculated as follows
(Group Record Types are described in section 3.3):
Old State New State State-Change Record Sent
----------- ----------- ------------------------
INCLUDE (A) INCLUDE (B) ALLOW(B-A), BLOCK(A-B)
INCLUDE (A) EXCLUDE () IS_EX()
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INCLUDE () EXCLUDE () IS_EX()
EXCLUDE () INCLUDE (B) TO_IN(B)
To cover the possibility of the State-Change Report being missed by
one or more multicast routers, it is retransmitted [Robustness
Variable]-1 more times, at intervals chosen at random from the range
(0, [Unsolicited Report Interval]). (These values are defined in
[IGMPv3, MLDv2].)
In the full version of IGMPv3, as was done with the first report, the
interface state for the affected group before and after the latest
change is compared, and the report records expressing the difference
are built and merged with the contents of the pending report, to
create the new State-Change report. However, it is optional that a
LW-IGMPv3 host merges with the contents of the pending report. If
the LW-IGMPv3 host does not merge with the contents of the pending
report, it transmits each report sequentially. Doing so can greatly
simplified the operation for scheduling the reports.
3.2. Action on Reception of a Query
When a lightweight version host receives a Query, it does not respond
immediately. Instead, it delays its response by a random amount of
time, bounded by the Max Resp Time value derived from the Max Resp
Code in the received Query message [IGMPv3, MLDv2]. The system may
receive a variety of Queries on different interfaces and of different
kinds (e.g., General Queries, Group-Specific Queries, and Group-and-
Source-Specific Queries), each of which may require its own delayed
response.
Before scheduling a response to a Query, the system must first
consider previously scheduled pending responses and in many cases
schedule a combined response. Therefore, the lightweight version
host must be able to maintain the following state:
o A timer per interface for scheduling responses to General Queries.
o A per-group and interface timer for scheduling responses to Group-
Specific and Group-and-Source-Specific Queries.
o A per-group and interface list of sources to be reported in the
response to a Group-and-Source-Specific Query.
LW-IGMPv3 inherits most of the rules that are used to determine if a
Report needs to be scheduled from the full version. The different
point is regarding the simplification of EXCLUDE filter-mode and the
type of Report to schedule as detailed in section 3.3.
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While it is optional that a LW-IGMPv3 host merges with the contents
of the pending report for unsolicited report (i.e. State-Change
report) as mentioned in the previous section, if the received Query
is a Group-and-Source-Specific Query and there is a pending response
for this group with a non-empty source-list, then the group source
list is augmented to contain the list of sources in the new Query and
a single response is scheduled using the group timer as with the full
version host. The new response is then scheduled to be sent at the
earliest of the remaining time for the pending report and the
selected delay.
3.3. Applicable Group Record Types
Among Group Record Types defined in the full IGMPv3, several record
types are not used in LW-IGMPv3 as some of the processes related to
the filter mode change to the EXCLUDE mode are eliminated and some of
the report messages are converged with a record having null source
address list. All of the record types of report messages used by the
full and lightweight version protocols are shown as follows:
IGMPv3 LW-IGMPv3 Comments
-------- --------- -------------------------------------
IS_EX() IS_EX() Query response for (*,G) join
IS_EX(x) N/A Query response for EXCLUDE (x,G) join
IS_IN(x) ALLOW(x) Query response for INCLUDE (x,G) join
ALLOW(x) ALLOW(x) INCLUDE (x,G) join
BLOCK(x) BLOCK(x) INCLUDE (x,G) leave
TO_IN(x) TO_IN(x) Change to INCLUDE (x,G) join
TO_IN() TO_IN() (*,G) leave
TO_EX(x) N/A Change to EXCLUDE (x,G) join
TO_EX() IS_EX() (*,G) join
where "x" represents non-null source address list and "()" represents
null source address list. For instance, IS_EX() means a report whose
record type is IS_EX with null source address list. "N/A" represents
not applicable (or no use) because the corresponding operation should
not occur in the lightweight version protocols.
LW-IGMPv3 does not use EXCLUDE filter-mode with non-null source
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address list. And a multicast router creates the same state when it
receives a report message containing either of IS_EX or TO_EX record
types. Therefore, LW-IGMPv3 integrates the TO_EX operation to the
IS_EX operation.
When a LW-IGMPv3 host needs to make a query response for the state of
INCLUDE (x,G) join, the host makes the response whose message type is
expressed with ALLOW(x), instead of using IS_IN record type, for
router's processing of the two messages are completely the same, the
IS_IN(x) type is eliminated for simplification.
A LW-IGMPv3 host does not use EXCLUDE mode, while TO_IN record is
used with the following situation: the host firstly launches an
application (AP1) that requests INCLUDE (x,G) join, and it sends
ALLOW(x). Then the host launches another application (AP2) that
joins (*,G), and it sends IS_EX(). In this condition, when AP2
terminates but AP1 keeps working on the lightweight version host, the
host sends a report with TO_IN(x) record type for [Robustness
Variable] times.
4. LW-IGMPv3 Protocol for Multicast Routers
The major difference between the full and lightweight version
protocol on the router is that filter-mode is discarded for the
lightweight version, as section 2.2 mentioned. Then the IGMP state
maintained by the router for each attached network can be simplified
as:
(multicast address, group timer, (source records))
where the source record includes pairs of source address and its
corresponding source timer. In this model, the filter-mode is
omitted and the meaning of the group timer is redefined to implement
simplified processing.
4.1. Group Timers and Source Timers in the Lightweight Version
The source timer is kept for each source record and it is updated
when the source is present in a received report. It indicates the
validity of the sources and needs to be referred when the router
takes its forwarding decision.
The group timer being used in the full version of IGMPv3 as a
mechanism for transitioning the router's filter-mode from EXCLUDE to
INCLUDE, is now redefined for the identification of the non-source-
specific receiving states, i.e., (*,G)join. Once a group record of
IS_EX() is received, the group timer is used to represent this (*,G)
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group join. The expiration of the group timer indicates that there
are no listeners on the attached network for this (*,G) group. Then
if at this moment there are unexpired sources (whose source timers
are greater than zero), the router will change to receiving for those
sources. The role of the group timer can be summarized as follows:
Group Timer Value Actions/Comments
------------------ --------------------------------------
G_Timer > 0 All members in this group.
G_Timer == 0 No more listeners to this (*,G) group.
If all source timers have expired then
delete group record. If there are
still source record timers running,
use those source records with running
timers as the source record state.
The operation related to the group and source timers has some
difference compared with the full IGMPv3. In the full version, if a
source timer expires under the EXCLUDE router filter-mode, its
corresponding source record is not deleted until the group timer
expires. They are kept for indicating undesired sources. In the
lightweight version, since there is no need to keep such records for
blocking specific sources, if a source timer expires, its source
record should be deleted immediately, not waiting for the time-out of
the group timer.
4.2. Source-Specific Forwarding Rules
A multicast router needs to consult IGMPv3 state information when it
makes decisions on forwarding a datagram from a source to its
attached network. In the full IGMPv3, the router filter-mode and
source timer are taken as the necessary judging conditions. In LW-
IGMPv3, because of the absence of the router filter-mode, the group
timer and source timer could be used for such decisions. The
forwarding suggestion made by LW-IGMPv3 to the routing protocols can
be summarized as follows:
Group Timer Source Timer Action
------------ ------------------ -----------------------
G_Timer == 0 S_TIMER > 0 Suggest to forward
traffic from source
G_Timer == 0 S_TIMER == 0 Suggest to stop
forwarding traffic from
source and remove
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source record. If there
are no more source
records for the group,
delete group record
G_Timer == 0 No Source Elements Suggest not to forward
traffic from the source
G_Timer > 0 S_TIMER >= 0 Suggest to forward
traffic from source
G_Timer > 0 No Source Elements Suggest to forward
traffic from source
4.3. Reception of Current-State Records
When receiving Current-State Records, the LW-IGMPv3 router resets its
group or source timers and updates its source list within the group.
For source-specific group reception state (G_Timer==0), the source
list includes sources to be forwarded by the router, while in non-
source-specific group reception (G_Timer>0) the source list remembers
the sources to be forwarded after toggling to source-specific
reception state.
The following table describes the action taken by a multicast router
after receiving Current-State Records. The notations have the same
meaning as that in the full IGMPv3.
Old New
Source Source
Group Timer List Report Rec'd List Actions
------------ ------ ------------ ------ -----------
G_Timer == 0 A IS_IN(B) A+B (B)=GMI
G_Timer == 0 A IS_EX() A G_Timer=GMI
G_Timer > 0 A IS_IN(B) A+B (B)=GMI
G_Timer > 0 A IS_EX() A G_Timer=GMI
And the above table could be further simplified for the processes
that are completely same for the two values of the G_Timer:
Old New
Source Source
List Report Rec'd List Actions
------ ------------ ------ -----------
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A IS_IN(B) A+B (B)=GMI
A IS_EX() A G_Timer=GMI
Without EXCLUDE filter-mode, a router's process on receiving Current-
State Record is simple: when a router receives an IS_IN report, it
appends the reported source addresses to the previous source list
with their source timers set to GMI. Upon receiving an IS_EX()
report, the router sets the non-source-specific receiving states with
GMI group timer value and keeps the previous source list without
modification.
4.4. Reception of Source-List-Change and Filter-Mode-Change Records
On receiving Source-List-Change and Filter-Mode-Change Records, the
LW-IGMPv3 router needs to reset its group and source timers, update
its source list within the group, or trigger group queries. The
queries are sent by the router for the sources that are requested to
be no longer forwarded to a group. The table below describes the
state change and the actions that should be taken.
Old New
Source Source
Group Timer List Report Rec'd List Actions
------------ ------ ------------ ------ -------------
G_Timer == 0 A ALLOW(B) A+B (B)=GMI
G_Timer == 0 A BLOCK(B) A Send Q(G,A*B)
G_Timer == 0 A TO_IN(B) A+B (B)=GMI
Send Q(G,A-B)
G_Timer > 0 A ALLOW(B) A+B (B)=GMI
G_Timer > 0 A BLOCK(B) A Send Q(G,A*B)
G_Timer > 0 A TO_IN(B) A+B (B)=GMI
SendQ(G,A-B)
Send Q(G)
The table could be further simplified by merging duplicate lines:
Old New
Source Source
List Report Rec'd List Actions
------ ------------ ------ ----------------------
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A ALLOW(B) A+B (B)=GMI
A BLOCK(B) A Send Q(G,A*B)
A TO_IN(B) A+B (B)=GMI
Send Q(G,A-B)
If G_Timer>0 Send Q(G)
5. Interoperability
LW-IGMPv3/LW-MLDv2 hosts and routers should interoperate gracefully
with the full version protocols [IGMPv3, MLDv2]. Also, LW-IGMPv3/LW-
MLDv2 hosts and routers should interoperate gracefully with hosts and
routers running IGMPv1/v2 or MLDv1.
5.1. Interoperation with the Full Version of IGMPv3
Eliminating EXCLUDE filter-mode from the full version protocols
simplifies the processes inside the host and router. On the other
hand, LW-IGMPv3 does not introduce any change on the message format
of the group query and report messages the full version protocols
use. Therefore, the group member sends a subset of IGMPv3 report
messages, which can be recognized by a multicast router running the
full or the lightweight IGMPv3 protocol on the same LAN.
A LW-IGMPv3 router translates IS_EX(x) and TO_EX(x) records that are
used with the full IGMPv3 but not used with LW-IGMPv3. When a LW-
IGMPv3 router receives these report messages from the full version
host, it translates them to IS_EX() records and makes the
corresponding behavior. All possible record types are compared as
follows:
IGMPv3 Report LW-IGMPv3 Equivalent
------------- --------------------
IS_IN(x) IS_IN(x)
IS_EX(x) IS_EX()
TO_IN(x) TO_IN(x)
TO_EX(x) IS_EX()
ALLOW(x) ALLOW(x)
BLOCK(x) BLOCK(x)
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5.2. Interoperation with IGMPv1/IGMPv2
The LW-IGMPv3 protocol basically adopts the same Host/Group
Compatibility Mode and keeps Querier Present timers for IGMPv1 and
IGMPv2. Their definition and processing is the same as that of
IGMPv3.
5.2.1. Behavior of Group Members
A host's compatibility mode is determined from the Host Compatibility
Mode variable which can be in one of three states: IGMPv1, IGMPv2 or
IGMPv3. The Host Compatibility Mode of an interface is set to IGMPv2
and IGMPv2 Querier Present is set to Older Version Querier Present
Timeout second (defined in [IGMPv3]) whenever an IGMPv2 General Query
is received on that interface. The Host Compatibility Mode of an
interface is set to IGMPv1 and IGMPv1 Querier Present is set to Older
Version Querier Present Timeout second whenever an IGMPv1 Membership
Query is received on that interface. Based on the Host Compatibility
Mode variable, a host acts using the IGMPv3, IGMPv2, or IGMPv1
protocol on that interface
While above manner is inherited from the definition of [IGMPv3], LW-
IGMPv3 may enable to configure the Host Compatibility Mode variable
by other means: when a LW-IGMPv3 host is placed on a link where there
are IGMPv1/IGMPv2 hosts, a host may allow its IGMPv3 report message
to be suppressed by an IGMPv1 or IGMPv2 report message.
5.2.2. Behavior of Multicast Routers
When Group Compatibility mode is IGMPv2 or IGMPv1, a LW-IGMPv3 router
translates the following IGMPv2 or IGMPv1 messages for that group to
their IGMPv2 or IGMPv1 equivalents:
IGMP Message LW-IGMPv3 Equivalent
------------- --------------------
v1 Report IS_EX()
v2 Report IS_EX()
v2 Leave TO_IN()
6. Implementation Considerations
The lightweight protocols requires no additional burden on the
implementation of the related protocols or systems, e.g. IGMP/MLD
snooping, multicast routing protocol, and operation of application
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sockets, while the processing loads on the switches and routers that
running IGMPv3 (snooping) and multicast routing protocols could be
greatly decreased.
In the following sections, the implementation related topics are
described for the lightweight version protocols.
6.1. Implementation of Source-Specific Multicast
[IGMP-SSM] illustrates the requirements of implementation of Source-
Specific Multicast (SSM) on IGMPv3/MLDv2 hosts and routers. The
lightweight protocol does not impose any bad influences on an SSM
application. The requirements of LW-IGMPv3/LW-MLDv2 for supporting
SSM are illustrated below.
A LW-IGMPv3/LW-MLDv2 host should not send a non-source-specific join,
i.e. IS_EX(), and IGMPv2 Leave and MLDv1 Done messages for the
application whose multicast address is in the SSM address range. The
reception of a non-source-specific join with an SSM group address
should indicate an error to the application. The SSM-aware router
will ignore IS_EX() reports with SSM addresses. Other types of
Reports should be processed normally.
6.2. Implementation of Multicast Source Filter (MSF) APIs
Multicast Source Filter (MSF) APIs [MSF] defines (1) IPv4 Basic MSF
API, (2) IPv4 Advanced MSF API, (3) Protocol-Independent Basic MSF
API, and (4) Protocol-Independent Advanced MSF API.
According to the MSF APIs definition, a LW-IGMPv3 host should
implement at least one of IPv4 Basic MSF API and Protocol-Independent
Basic MSF API, and a LW-MLDv2 host should implement Protocol-
Independent Basic MSF API. Other APIs, IPv4 Advanced MSF API and
Protocol-Independent Advanced MSF API, are optional to implement in
LW-IGMPv3/LW-MLDv2 host.
7. Security Considerations
The security consideration is the same as that of the full version of
IGMPv3/MLDv2.
8 Normative References
[KEYWORDS] Bradner, S., "Key words for use in RFCs to indicate
requirement levels," RFC 2119, March 1997.
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[IGMPv3] Cain, B., Deering, S., Kouvelas, I., Fenner, B., and
Thyagarajan, A., "Internet Group Management Protocol, Version3,"
RFC 3376, October 2002.
[MLDv2] Vida, R. and Costa, L., "Multicast Listener Discovery Version
2 (MLDv2) for IPv6," RFC 3810, June 2004.
9 Informative References
[SSM] Holbrook, H. and Cain, B., "Source-Specific Multicast for IP,"
RFC 4607, August 2006.
[IGMPv2] Fenner, W., "Internet Group Management Protocol, Version 2,"
RFC 2236, November 1997.
[MLDv1] Deering, S., Fenner, W., and Haberman, B., "Multicast
Listener Discovery (MLD) for IPv6," RFC 2710, October 1999.
[IGMP-SSM] Holbrook, H., Cain, B., and Haberman, B., "Using Internet
Group Management Protocol Version 3 (IGMPv3) and Multicast
Listener Discovery Protocol Version 2 (MLDv2) for Source-Specific
Multicast," RFC 4604, August 2006.
[MSF] Thaler, D., Fenner, B., and Quinn, B., "Socket Interface
Extensions for Multicast Source Filters," RFC 3678, January 2004.
Author's Addressess
Hui Liu
Huawei Technologies Co., Ltd.
Huawei Bld., No.3 Xinxi Rd.,
Shang-Di Information Industry Base,
Hai-Dian Distinct, Beijing 100085,
China
Email: Liuhui47967@huawei.com
Wei Cao
Huawei Technologies Co., Ltd.
Huawei Bld., No.3 Xinxi Rd.,
Shang-Di Information Industry Base,
Hai-Dian Distinct, Beijing 100085,
China
Email: caowayne@huawei.com
Liu et. al. [Page 15]
Internet Draft Lightweight IGMPv3 and MLDv2 December 2006
Hitoshi Asaeda
Graduate School of Media and Governance
Keio University
5322 Endo, Fujisawa, Kanagawa 252-8520,
Japan
Email: asaeda@wide.ad.jp
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Liu et. al. [Page 16]
Internet Draft Lightweight IGMPv3 and MLDv2 December 2006
This document is subject to the rights, licenses and restrictions
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Acknowledgment
The author would like to thank magma and mboned mailing lists for
discussion and contribution for the ideas.
Liu et. al. [Page 17]
