Multicast Support for 4rd
draft-sarikaya-softwire-4rdmulticast-03
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| Last updated | 2012-07-16 | ||
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draft-sarikaya-softwire-4rdmulticast-03
Network Working Group B. Sarikaya
Internet-Draft Huawei USA
Intended status: Standards Track July 17, 2012
Expires: January 18, 2013
Multicast Support for 4rd
draft-sarikaya-softwire-4rdmulticast-03.txt
Abstract
This memo specifies 4rd technology's multicast component so that IPv4
hosts can receive multicast data from IPv4 servers over an IPv6
network. In 4rd Translation Multicast solution for 4rd and
translation variant of MAP, MAP-T, IGMP messages are translated into
MLD messages at the CE router which is IGMP/MLD Proxy and sent to the
network in IPv6. 4rd Border Relay does the reverse translation and
joins IPv4 multicast group for 4rd hosts. Border Relay as multicast
router receives IPv4 multicast data and translates the packet into
IPv6 multicast data and sends downstream on the multicast tree.
Member CEs receive multicast data, translate it back to IPv4 and
transmit to the hosts. In 4rd encapsulation solution for
encapsulation variant of MAP, MAP-E, IGMP Proxy at the 4rd Customer
Edge router uses IPv4-in-IPv6 tunnel established by MAP-E to exchange
IGMP messages to establish multicast state at MAP Border Relay so
that MAP Border Relay can tunnel IPv4 multicast data to IPv4 hosts
connected to MAP Customer Edge device.
Status of this Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
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and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on January 18, 2013.
Copyright Notice
Copyright (c) 2012 IETF Trust and the persons identified as the
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document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
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described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. Requirements . . . . . . . . . . . . . . . . . . . . . . . . . 4
4. Architecture . . . . . . . . . . . . . . . . . . . . . . . . . 4
4.1. 4rd Translation Architecture . . . . . . . . . . . . . . . 5
4.2. Encapsulation Multicast Architecture . . . . . . . . . . . 6
5. 4rd Translation Multicast Operation . . . . . . . . . . . . . 7
5.1. Address Translation . . . . . . . . . . . . . . . . . . . 7
5.1.1. Learning Multicast Prefixes for IPv4-embedded
IPv6 Multicast Addresses . . . . . . . . . . . . . . . 8
5.2. Protocol Translation . . . . . . . . . . . . . . . . . . . 9
5.3. Supporting IPv6 Multicast in 4rd Translation Multicast . . 10
6. Encapsulation Multicast Operation . . . . . . . . . . . . . . 11
7. Security Considerations . . . . . . . . . . . . . . . . . . . 12
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12
9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 12
10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 12
10.1. Normative References . . . . . . . . . . . . . . . . . . . 12
10.2. Informative references . . . . . . . . . . . . . . . . . . 14
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 15
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1. Introduction
With IPv4 address depletion on the horizon, many techniques are being
standardized for IPv6 migration including 4rd
[I-D.ietf-softwire-map], [I-D.ietf-softwire-4rd]. 4rd enables IPv4
hosts to communicate with external hosts using IPv6 only ISP network.
4rd Customer Edge (CE) device's LAN side is dual stack and WAN side
is IPv6 only. CE tunnels/translates IPv4 packets received from the
LAN side to 4rd Border Relays (BR). BRs have anycast IPv6 addresses
and receive encapsulated/translated packets from CEs over a virtual
interface. 4rd operation is stateless. Packets are received/ sent
independent of each other and no state needs to be maintained.
4rd as defined in [I-D.ietf-softwire-map] and [I-D.ietf-softwire-4rd]
is unicast only. It does not support multicast. In this document we
specify how multicast from home IPv4 users can be supported in 4rd.
In case IPv6 network is multicast enabled, 4rd can provide multicast
service to the hosts using 4rd Multicast Translation based solution.
A Multicast Translator can be used that receives IPv6 multicast group
management messages in MLD and generates corresponding IPv4 group
management messages in IGMP and sends them to IPv4 network in 4rd
Border Relay. We use [I-D.ietf-softwire-4rd] for sending IPv6
multicast data in IPv4 to the CE routers. At 4rd CE router another
translator is needed to translate IPv6 multicast data into IPv4
multicast data.
In case of 4rd variants that use encapsulation such as MAP-E we
integrate 4rd multicast into the MAP-E tunnel resulting in a
multicast tunneling protocol. Multicast tunneling protocol has the
advantage of not requiring multicast enabled IPv6 network between CE
routers and MAP (4rd) BRs.
When MAP-E CE router receives an IGMP join message to an Any-Source
Multicast (ASM) [RFC1112] or Source-Specific Multicast (SSM) group
[RFC4607], it sends an aggregated IGMP membership report message in
the IPv4-in-IPv6 tunnel to the border relay. MAP-E BR joins the
source in the multicast infrastructure and sends multicast data
downstream to all member CEs in the IPv4-in-IPv6 tunnel. When a CE
has no membership state, i.e. after all member hosts leave the
group(s), its state with the BR expires and the CE can send the next
join message in anycast.
In this document we address 4rd multicast problem and propose two
architectures: Multicast Tunneling and Multicast Translation based
solutions. Section 2 is on terminology, Section 3 is on
requirements, Section 4 is on architecture, Section 5 is on multicast
translation protocol, Section 6 is on multicast tunneling protocol
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and Section 7 states security considerations.
2. Terminology
This document uses the terminology defined in
[I-D.ietf-softwire-map], [I-D.ietf-softwire-4rd], [RFC3810] and
[RFC3376].
3. Requirements
This section states requirements on 4rd multicast support protocol.
IPv4 hosts connected to 4rd CE router MUST be able to join multicast
groups in IPv4 and receive multicast data.
Any source multicast (ASM) SHOULD be supported and source specific
multicast (SSM) MUST be supported.
In case of translation solution, 4rd CE MUST support IGMP to MLD
translation. 4rd CE MUST be MLD Proxy as defined in [RFC4605].
In case of translation solution, 4rd BR MUST support MLD Querier. 4rd
BR MUST support MLD to IGMP translator upstream.
MAP (4rd) CE MAY support IGMP Proxy as defined in [RFC4605].
MAP (4rd) BR MAY support IGMP router downstream. 4rd BR may support
PIM protocol upstream.
4. Architecture
In 4rd, there are hosts (possibly IPv4/ IPv6 dual stack) served by
4rd Customer Edge device. CE is dual stack facing the hosts and IPv6
only facing the network or WAN side. 4rd CE may be local IPv4 Network
Address and Port Translation (NAPT) box [RFC3022] by assigning
private IPv4 addresses to the hosts. 4rd CEs in the same domain may
use shared public IPv4 addresses on their WAN side and if they do
they should avoid ports outside of the allocated port set for NAPT
operation. At the boundary of the network there is 4rd Border Relay.
BR receives IPv4 packets tunneled in IPv6 from CE and decapsulates
them and sends them out to IPv4 network.
Unicast 4rd is stateless except for the local NAPT at the CE. Each
IPv4 packet sent by CE treated separately and different packets from
the same CE may go to different BRs or CEs. CE encapsulates IPv4
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packet in IPv6 with destination address set to BR address (usually
anycast IPv6 address). BR receives the encapsulated packet and
decapsulates and send it to IPv4 network. CEs are configured with
domain 4rd Prefixes, IPv6 Prefixes and with an BR IPv6 anycast
address. BR receives IPv4 packets addressed to this ISP and from the
destination address it extracts the destination host's IPv4 address
and uses this address as destination address and encapsulates the
IPv4 packet in IPv6 and sends it to IPv6-only network.
4.1. 4rd Translation Architecture
In case IPv6 only network is multicast enabled, translation multicast
architecture can be used. CE implements IGMP Proxy function
[RFC4605] towards the LAN side and MLD Proxy on its WAN interface.
IPv4 hosts send their join requests (IGMP Membership Report messages)
to CE. CE as a MLD proxy sends aggregated MLD Report messages
upstream towards BR. CE replies MLD membership query messages with
MLD membership report messages based on IGMP membership state in the
IGMP/MLD proxy.
BR is MLD querier on its WAN side. On its interface to IPv4 network
BR may either have IGMP client or PIM. PIM being able to support
both IPv4 and IPv6 multicast should be preferred. BR receives MLD
join requests, extracts IPv4 multicast group address and then joins
the group upstream, possibly by issuing a PIM join message.
IPv4 multicast data received by the BR as a leaf node in IPv4
multicast distribution tree is translated into IPv6 multicast data by
the translator using [I-D.ietf-softwire-4rd] and then sent downstream
to the IPv6 part of the multicast tree to all downstream routers that
are members. IPv6 data packet eventually gets to the CE. At the CE,
a reverse [I-D.ietf-softwire-4rd] operation takes place by the
translator and then IPv4 multicast data packet is sent to the member
hosts on the LAN interface. [I-D.ietf-softwire-4rd] is modified to
handle multicast addresses.
In order to support SSM, IGMPv3 MUST be supported by the host, CE and
BR. For ASM, BR MUST be the Rendezvous Point (RP).
4rd Translation Multicast solution uses the multicast 46 translator
in not one but two places in the architecture: at the CE router and
at the Border Relay. IPv4 multicast data received at 4rd BR goes
through a [I-D.ietf-softwire-4rd] header-mapping into IPv6 multicast
data at the BR and another [I-D.ietf-softwire-4rd] header-mapping
back to IPv4 multicast data at the CE router. Encapsulation variant
of [I-D.ietf-softwire-4rd] is not used.
All the elements of 4rd translation-based multicast support system
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are shown in Figure 1.
Dual Stack Hosts IPv4
+----+ Network
| H1 | +----------+ IPv6 +-------------+
| | | CE | | BR |
+----+ |Translator| only | Translator |
| 4rd | | 4rd |
+----+ | | network | |IGMP| +
| H2 | ---|IGMP-MLD |--------- -- |MLD | or | IPv6
+----+ | Proxy | |Querier |PIM | Network
+----+ +----------+ +-------------+
| H3 |
+----+
Figure 1: Architecture of 4rd Translation Multicast
4.2. Encapsulation Multicast Architecture
Encapsulation variant of MAP (4rd) (MAP-E) network lends itself
easily to the Multicast Tunneling architecture. Dual stack hosts are
connected to the Customer Edge router and it is multicast enabled.
It is assumed that IPv6 only network is the unicast only network. At
the boundary of the network MAP (4rd) Border Relay is connected to
the native multicast backbone infrastructure.
We place IGMP Proxy at the CE router. CE router serves all the
connected hosts. For multicast traffic, CE Router uses MAP (4rd)
tunneling interface with MAP (4rd) BR to send/receive IGMP messages
using IPv4-in-IPv6 tunnel [RFC2473].
MAP (4rd) BR is IGMP Router towards the CEs and it could be IGMP
Router or PIM router upstream. A given relay and all CEs connected
to it can be considered to be on a separate logical link. On this
link, gateways and relay communicate using IPv4-in-IPv6 tunneling to
transmit and receive multicast control messages for membership
management and multicast data from the relay to the gateways.
All the elements of MAP (4rd) multicast support system with tunneling
are shown in Figure 2.
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Dual Stack Hosts IPv4
+----+ Network
| H1 | IPv6
+----+ +-------+ only +--------------+ +
+----+ | CE | network | BR |
| H2 | ---| IGMP |--- -- |IGMP | IGMP | IPv6
+----+ | Proxy | |Router| PIM | Network
+----+ +-------+ +--------------+
| H3 |
+----+
Figure 2: Architecture of 4rd Multicast Tunneling
5. 4rd Translation Multicast Operation
In this section we specify how the host can subscribe and receive
IPv4 multicast data from IPv4 content providers based on the
architecture defined in Figure 1 in two parts: address translation
and protocol translation.
5.1. Address Translation
IPv4-only H1 will join IPv4 multicast group by sending IGMP
Membership Report message upstream towards the IGMP Proxy in
Figure 1. MLD Proxy first creates a synthesized IPv6 address of IPv4
multicast group address using IPv4-embedded IPv6 multicast address
format [I-D.ietf-mboned-64-multicast-address-format]. ASM_MPREFIX64
for any source multicast groups and SSM_MPREFIX64 for source specific
multicast groups are used. Both are /96 prefixes.
In both ASM_MPREFIX64 and SSM_MPREFIX64, M bit MUST be set to 1 to
indicate that an IPv4 address is embedded in the last 32 bits of the
multicast IPv6 address. ASM_MPREFIX64 values are formed by setting
flgs bits to make it an embedded RP prefix by setting R bit to 1 and
P and T bits to 1 as shown in Figure 3 [RFC4291], [RFC3306],
[RFC3956].
| 8 | 4 | 4 | 4 | 76 | 32 |
+--------+----+----+----+------------------------------+----------+
|11111111|0111|scop|1000| sub-group-id |v4 address|
+--------+----+----+----+-----------------------------------------+
Figure 3: ASM_MPREFIX64 Formation
Each translator in the upstream BR is assigned a unique ASM_MPREFIX64
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prefix. CE (MLD Proxy in CE) can learn this value by means out of
scope with this document. With this, CE can easily create an IPv6
multicast address from the IPv4 group address a.b.c.d that the host
wants to join.
Source-Specific Multicast (SSM) can also be supported similar to the
Any Source Multicast (ASM) described above. In case of SSM, IPv4
multicast addresses use 232.0.0.0/8 prefix. IPv6 SSM_MPREFIX64
values are formed by setting R bit to zero, P and T bits to 1. This
gives FF3x00008x::/96 as the SSM prefix. This prefix is referred to
as SSM_PREFIX64 Figure 4.
| 8 | 4 | 4 | 16 | 4 | 60 | 32 |
+--------+----+----+-----------+----+------------------+----------+
|11111111|0011|scop|00.......00|1000| sub-group-id |v4 address|
+--------+----+----+-----------+----+------------------+----------+
Figure 4: SSM_MPREFIX64 Formation
Since SSM translation requires a unique address for each IPv4
multicast source, an IPv6 unicast prefix must be configured to the
translator in the upstream BR to represent IPv4 sources. This prefix
is prepended to IPv4 source addresses in translated packets.
The join message from the host for the group ASM_MPREFIX64:a.b.c.d or
SSM_MPREFIX64:a.b.c.d or an aggregate join message will be received
by MLD querier at the BR. BR as multicast anchor checks the group
address and recognizes ASM_MPREFIX64 or SSM_MPREFIX64 prefix. It
next checks the last 32 bits is an IPv4 multicast address in range
224/8 - 239/8. If all checks succeed, IGMPv4 Client joins a.b.c.d
using IGMP on its IPv4 interface.
Joining IPv4 groups can also be done using PIM since PIM supports
both IPv4 and IPv6. The advantage of using PIM is that there is no
need to enable IGMP support in neighboring IPv4 routers. The
advantage of using IGMP is that IGMP is a simpler protocol and it is
supported by a wider range of routers. The use of PIM or IGMP is
left as an implementation choice.
5.1.1. Learning Multicast Prefixes for IPv4-embedded IPv6 Multicast
Addresses
CE can be pre-configured with Multicast Prefix64 of ASM_MPREFIX64 and
SSM_MPREFIX64 that are supported in their network. However
automating this process is also desired.
[I-D.wing-behave-learn-prefix] suggests several methods including
DHCPv6.
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A new DHCPv6 option, OPTION_AFT_PREFIX_DHCP, can be defined for this
purpose. The option contains IPv6 ASM and SSM prefixes. The host
can request these prefixes by sending this option in its request to
the DHCP server and the server replies with the option containing the
prefixes.
After the host gets the multicast prefixes, when an application in
the host wishes to join an IPv4 multicast group the host MUST use
ASM_MPREFIX64 or SSM_MPREFIX64 and then obtain the synthesized IPv6
group address before sending MLD join message.
5.2. Protocol Translation
The hosts will send their subscription requests for IPv4 multicast
groups upstream to the default router, i.e. Costumer Edge device.
After subscribing the group, the host can receive multicast data from
the CE. The host implements IGMP protocol's host part.
Customer Edge device is IGMP Proxy facing the LAN interface. After
receiving the first IGMP Report message requesting subscription to an
IPv4 multicast group, a.b.c.d, MLD Proxy in the CE's WAN interface
synthesizes an IPv6 multicast group address corresponding to a.b.c.d
and sends an MLD Report message upstream to join the group.
When CE is a NAT or NAPT box assigning private IPv4 addresses to the
hosts, IP Multicast requirements for a Network Address Translator
(NAT) and a Network Address Port Translator (NAPT) stated in
[RFC5135] apply to IGMP messages and IPv4 multicast data packets.
4rd BR as MLD router receives/sends MLD messages on its WAN
interface. 4rd BR does all corresponding actions on its upstream
interface connected to IPv4 network in IGMP/PIM in IPv4. The two
sides on the BR share MLD membership state.
When 4rd BR receives IPv4 multicast data for an IPv4 group a.b.c.d it
[I-D.ietf-softwire-4rd] translates/encapsulates IPv4 packet into IPv6
multicast packet and sends it to IPv6 synthesized address
corresponding to a.b.c.d using ASM_MPREFIX64 or SSM_MPREFIX64. The
header mapping described in [I-D.ietf-softwire-4rd] Section 4.2
(using Table 1) is used except for mapping the source and destination
addresses. In this document we use the multicast address translation
described in Section 5.1 and propose it as a complementary
enhancement to the translation algorithm in [I-D.ietf-softwire-4rd].
The IP/ICMP translation translates IPv4 packets into IPv6 using
minimum MTU size of 1280 bytes (Section 4.1 in
[I-D.ietf-softwire-4rd]) but this can be changed for multicast. Path
MTU discovery for multicast is possible in IPv6 so 4rd BR can perform
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path MTU discovery for each ASM group and use these values instead of
1280. For SSM, a different MTU value MUST be kept for each SSM
channel. Because of this 8 bytes added by IPv6 fragment header in
each data packet can be tolerated.
Since multicast address translation does not preserve checksum
neutrality, [I-D.ietf-softwire-4rd] translator/encapsulator at 4rd BR
must however modify the UDP checksum to replace the IPv4 addresses
with the IPv6 source and destination addresses in the pseudo-header
which consists of source address, destination address, protocol and
UDP length fields before calculating the new checksum.
IPv6 multicast data must be translated back to IPv4 at the 4rd CE
(e.g. using Table 2 in Section 4.2 of [I-D.ietf-softwire-4rd]). Such
a task is much simpler than the translation at 4rd BR because IPv6
header is much simpler than IPv4 header and IPv4 link on the LAN side
of 4rd CE is a local link. The packet is sent on the local link to
IPv4 group address a.b.c.d for IPv6 group address of ASM_MPREFIX64:
a.b.c.d or SSM_MPREFIX64:a.b.c.d.
In case an IPv4 multicast source sends multicast data with the don't
fragment (DF) flag set to 1, [I-D.ietf-softwire-4rd] header mapping
sets the D bit in IPv6 fragment header before sending the packet
downstream as in Fig. 3 in Section 4.2 of [I-D.ietf-softwire-4rd].
This feature of [I-D.ietf-softwire-4rd] preserves the semantics of DF
flag at the BR and CE.
Because 4rd is stateless, Multicast 4rd should stay faithful to this
as much as possible. Border Relay acts as the default multicast
querier for all CEs that have established multicast communication
with it. In order to keep a consistent multicast state between a CE
and BR, CE MUST use the same IPv6 multicast prefixes (ASM_MPREFIX64/
SSM_REFIX64) until the state becomes empty. After that point, the CE
may obtain different values for these prefixes, effectively changing
to a different 4rd BR.
5.3. Supporting IPv6 Multicast in 4rd Translation Multicast
IPv6 multicast can be supported natively in 4rd in case IPv6-only
network is multicast enabled. 4rd Customer Edge device has MLD Proxy
function. Proxy operation for MLD [RFC3810] is described in
[RFC4605].
CE receives MLD join requests from the hosts and then sends
aggregated MLD Report messages upstream towards BR. No address or
protocol translation is needed at the CE or at the BR. IPv6 Hosts in
4rd domain use any source multicast block FF0X [RFC4291] or source
specific multicast block FF3X::8000:0-FF3X::FFFF:FFFF for dynamic
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allocation by a host [RFC4607], [RFC3307].
4rd Border Relay is MLD querier. It serves all CEs downstream.
After receiving an MLD join message, BR sends PIM join message
upstream to join IPv6 multicast group. Multicast membership database
is maintained based on the aggregated Reports received from
downstream interfaces in the multicast tree.
4rd Border Relay is a Rendezvous Point (RP) for ASM groups. For SSM,
BR MUST support MLDv2.
IPv6 multicast data received from the Single Source Multicast or Any
Source Multicast sources are replicated according to the multicast
membership database and the data packets are sent downstream on the
multicast tree and eventually received by the CEs that have one of
more members of this multicast group.
MLD Proxy in the CE receives multicast data then forwards the packet
downstream. Each member host receives IPv6 multicast data packet
from its Layer 2 interface.
6. Encapsulation Multicast Operation
When a host (H1, H2 or H3 in Figure 2) wants to join an IPv4
multicast group, it sends an IGMP report (IGMPv3 report for a source-
specific group) to CE router. CE router uses BR's anycast address
this CE router is configured with.
CE encapsulates IGMP report messages in IPv6 and sends it over the
tunnel to BR in anycast. After CE receives unicast address of BR, it
sends all subsequent IGMP messages in unicast.
BR (topologically closest to this CE router) receives the message
decapsulates it and then lets IGMP router to process it. Upstream an
IGMP Join message is sent to subscribe group G or a PIMv4 Join
message is sent if PIM is supported. BR establishes membership state
for group G. BR sends all related IGMP messages to this CE in unicast
using IPv4-in-IPv6 tunneling.
CE now has BR's unicast address which it uses to send all multicast
packets for group G. If CE receives multiple join messages for the
same group G, CE sends an aggregated join message to BR. If CE
receives another join message for a different group G', CE
encapsulates it and sends it in anycast to the BR.
After BR receives IGMP Join message it adds the tunnel to the CE in
its outgoing interface list for the group that the host wants to
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join. BR will send a join message towards the source of the
multicast group to build a multicast tree in the native multicast
infrastructure and becomes a leaf node in the multicast tree.
As for multicast data, the data packets from the source received at
the BR will be replicated to all interfaces in it's outgoing
interface list as well as the tunnel outgoing interface for all
member CEs. BR sends multicast data in IPv4-in-IPv6 tunnel to the CE
with the data packet encapsulated.
CE receives Multicast Data message over the tunnel interface
associated with the tunnel to BR. CE forwards the packet IGMP Proxy
which in its turn forward the message to the outgoing interfaces
joined by the hosts.
7. Security Considerations
4rd Encapsulation Multicast control and data message security can be
provided by the security architecture, mechanisms, and services
described in [RFC4301], [RFC4302] and [RFC4303]. 4rd Translation
Multicast control and data message security are as described in
[RFC4607] for source specific multicast.
8. IANA Considerations
TBD.
9. Acknowledgements
We are grateful to Remi Despres for his contributions to this
document. Mohamed Boucadair provided many comments offline that
helped us improve the document.
10. References
10.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2629] Rose, M., "Writing I-Ds and RFCs using XML", RFC 2629,
June 1999.
[RFC1112] Deering, S., "Host extensions for IP multicasting", STD 5,
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RFC 1112, August 1989.
[RFC4605] 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.
[RFC4607] Holbrook, H. and B. Cain, "Source-Specific Multicast for
IP", RFC 4607, August 2006.
[RFC3307] Haberman, B., "Allocation Guidelines for IPv6 Multicast
Addresses", RFC 3307, August 2002.
[RFC2491] Armitage, G., Schulter, P., Jork, M., and G. Harter, "IPv6
over Non-Broadcast Multiple Access (NBMA) networks",
RFC 2491, January 1999.
[RFC2473] Conta, A. and S. Deering, "Generic Packet Tunneling in
IPv6 Specification", RFC 2473, December 1998.
[RFC2765] Nordmark, E., "Stateless IP/ICMP Translation Algorithm
(SIIT)", RFC 2765, February 2000.
[RFC3022] Srisuresh, P. and K. Egevang, "Traditional IP Network
Address Translator (Traditional NAT)", RFC 3022,
January 2001.
[RFC3810] Vida, R. and L. Costa, "Multicast Listener Discovery
Version 2 (MLDv2) for IPv6", RFC 3810, June 2004.
[RFC3376] Cain, B., Deering, S., Kouvelas, I., Fenner, B., and A.
Thyagarajan, "Internet Group Management Protocol, Version
3", RFC 3376, October 2002.
[RFC4301] Kent, S. and K. Seo, "Security Architecture for the
Internet Protocol", RFC 4301, December 2005.
[RFC4302] Kent, S., "IP Authentication Header", RFC 4302,
December 2005.
[RFC4303] Kent, S., "IP Encapsulating Security Payload (ESP)",
RFC 4303, December 2005.
[RFC5135] Wing, D. and T. Eckert, "IP Multicast Requirements for a
Network Address Translator (NAT) and a Network Address
Port Translator (NAPT)", BCP 135, RFC 5135, February 2008.
[RFC6145] Li, X., Bao, C., and F. Baker, "IP/ICMP Translation
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Internet-Draft Multicast Support for 4rd July 2012
Algorithm", RFC 6145, April 2011.
[RFC6052] Bao, C., Huitema, C., Bagnulo, M., Boucadair, M., and X.
Li, "IPv6 Addressing of IPv4/IPv6 Translators", RFC 6052,
October 2010.
[I-D.ietf-softwire-map]
Troan, O., Dec, W., Li, X., Bao, C., Zhai, Y., Matsushima,
S., and T. Murakami, "Mapping of Address and Port (MAP)",
draft-ietf-softwire-map-01 (work in progress), June 2012.
[I-D.ietf-softwire-4rd]
Despres, R., Penno, R., Lee, Y., Chen, G., Jiang, S., and
M. Chen, "IPv4 Residual Deployment via IPv6 - a Stateless
Solution (4rd)", draft-ietf-softwire-4rd-03 (work in
progress), July 2012.
[I-D.ietf-mboned-64-multicast-address-format]
Boucadair, M., Qin, J., Lee, Y., Venaas, S., Li, X., and
M. Xu, "IPv6 Multicast Address Format With Embedded IPv4
Multicast Address",
draft-ietf-mboned-64-multicast-address-format-02 (work in
progress), May 2012.
10.2. Informative references
[RFC3306] Haberman, B. and D. Thaler, "Unicast-Prefix-based IPv6
Multicast Addresses", RFC 3306, August 2002.
[RFC3956] Savola, P. and B. Haberman, "Embedding the Rendezvous
Point (RP) Address in an IPv6 Multicast Address",
RFC 3956, November 2004.
[RFC4291] Hinden, R. and S. Deering, "IP Version 6 Addressing
Architecture", RFC 4291, February 2006.
[I-D.wing-behave-learn-prefix]
Wing, D., "Learning the IPv6 Prefix of a Network's IPv6/
IPv4 Translator", draft-wing-behave-learn-prefix-04 (work
in progress), October 2009.
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Internet-Draft Multicast Support for 4rd July 2012
Author's Address
Behcet Sarikaya
Huawei USA
5340 Legacy Dr. Building 175
Plano, TX 75074
Phone:
Email: sarikaya@ieee.org
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