Internet DRAFT - draft-perreault-mboned-igmp-mld-translation
draft-perreault-mboned-igmp-mld-translation
Network Working Group S. Perreault
Internet-Draft Viagenie
Intended status: Standards Track T. Tsou
Expires: October 12, 2012 Huawei Technologies (USA)
April 10, 2012
Internet Group Management Protocol (IGMP) / Multicast Listener Discovery
(MLD)-Based Multicast Translation ("IGMP/MLD Translation")
draft-perreault-mboned-igmp-mld-translation-01
Abstract
This document describes translation between IGMP and MLD. This
allows single-stack multicast nodes to participate in multicast
groups from a different address family. Both sending and receiving
is supported by this translation mechanism. Both any-source and
source-specific multicast (ASM and SSM) are supported as well.
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
working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
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 October 12, 2012.
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
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
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
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. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
4. Overview of Implementation Types . . . . . . . . . . . . . . . 4
4.1. Proxy . . . . . . . . . . . . . . . . . . . . . . . . . . 4
4.1.1. Mixed IPv4/IPv6 Networks . . . . . . . . . . . . . . . 5
4.2. Multicast Router . . . . . . . . . . . . . . . . . . . . . 6
5. Signalling Translation . . . . . . . . . . . . . . . . . . . . 6
5.1. IP Headers . . . . . . . . . . . . . . . . . . . . . . . . 6
5.1.1. Addresses . . . . . . . . . . . . . . . . . . . . . . 6
5.1.2. Router-Alert Option . . . . . . . . . . . . . . . . . 7
5.2. IGMP/MLD Translation . . . . . . . . . . . . . . . . . . . 7
5.2.1. Message Type Equivalences . . . . . . . . . . . . . . 7
5.2.2. The "Translated" Bit . . . . . . . . . . . . . . . . . 8
5.2.3. Maximum Response {Delay,Time} . . . . . . . . . . . . 12
5.2.4. Multicast Group Address . . . . . . . . . . . . . . . 13
5.2.5. Source Addresses . . . . . . . . . . . . . . . . . . . 14
5.2.6. Additional and Auxiliary Data . . . . . . . . . . . . 14
5.3. MTU Considerations . . . . . . . . . . . . . . . . . . . . 14
6. Data Transfer . . . . . . . . . . . . . . . . . . . . . . . . 14
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15
8. Security Considerations . . . . . . . . . . . . . . . . . . . 15
9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 15
10. Normative References . . . . . . . . . . . . . . . . . . . . . 15
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 16
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1. Introduction
This document specifies IGMP/MLD translation, a mechanism for IPv4-
IPv6 transition and coexistence. It enables single-stack (i.e.,
IPv4-only or IPv6-only) hosts to participate, either as listeners,
sources, or both, in multicast groups belonging to a different
address family.
This translation mechanism is intended to be considered as a "virtual
function" that can be implemented in a listener, in a multicast
router, in an IGMP/MLD proxy [RFC4605], in existing layer-2 equipment
(i.e. as a "bump in the wire"), or as a standalone translating
device. Therefore, this function could be located at the customer
network edge (e.g., in customer-premises equipment (CPE)) or at the
provider network edge (e.g., in a DSLAM for DSL networks, in a CMTS
for cable networks, etc.), or any other node reachable by IGMP/MLD
packets. Note that intputs and outputs of this translation function
can also be virtual. For example, translated packets need not
actually be sent on the wire if the function's output is fed directly
into a multicast router process (e.g., a PIM daemon) running on the
same host.
2. 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 [RFC2119].
The unqualified term "proxy" refers to an IGMP/MLD proxy as defined
in [RFC4605].
3. Overview
The translation function produces IGMPv1,2,3 packets from MLDv1,2
packets and vice-versa.
+-------------+
IGMPv1 --| |-- MLDv1
IGMPv2 --| Translation |-- MLDv2
IGMPv3 --| <-----> |
+-------------+
Virtual translation function
IPv4 addresses are mapped to IPv6 addresses and vice versa as defined
in [I-D.boucadair-64-multicast-address-format]. This mapping is
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stateless. This implies that arbitrary IPv6 addresses are not
handled. IPv6 addresses MUST be part of a predetermined prefix in
order to be translateable.
The statelessness of the translation function is considered a
desirable property, and is an objective of this specification. In
general, stateless network elements makes simpler designs, allows
better scalability, and requires less operational overhead.
This translation function is stateless when considering full IGMP or
MLD packets. Fragmented packets MUST be reassembled before they can
be fed to this translation function.
4. Overview of Implementation Types
The virtual translation function defined in this document can be
implemented in various ways. This section presents an overview of
some possibilities.
4.1. Proxy
As described in [RFC4605], an IGMP/MLD proxy is located between an
upstream network and one or more downstream networks. Listeners are
in the downstream networks while the rest of the multicast
infrastructure is upstream. It is possible to arrange multiple
proxies in a tree topology, where one proxy's upstream network is
another's downstream network.
The translation function MUST be logically situated between the proxy
function and the upstream network, as shown in Figure 1.
Upstream
|
+----+-----+
|Translator|
+----+-----+
|
+---+----+
| Proxy |
+-+-+-+-++
| | | |
Downstream(s)
Figure 1: IGMP/MLD translator proxy topology
There are two reasons for locating the translator upstream of the
proxy rather than downstream:
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1. Translating addresses on downstream interfaces could interfere
with Querier elections. As described in [RFC3376] section 6.6.2
and [RFC3810] section 7.6.2, IGMP and MLD routers elect a Querier
amongst themselves. The criteria for winning the election is
based on the source address of IGMP/MLD Queries. Having a
translator on a downstream interface would impose a new
constraint on the address mapping scheme: it would need to ensure
the same election result before and after applying the mapping.
This constraint is lifted when the translation is applied to the
upstream interface instead. Since a proxy acts as a client on
its upstream interface, it does not participate in Querier
elections.
2. There is only one upstream interface whereas there may be
multiple downstream interfaces. Applying the translation on the
upstream interface has the advantage of having a single
translation point, which can facilitate debugging and
troubleshooting.
Conceptually, translation is applied to messages sent upstream by the
client state machine and to messages received from upstream. This
document specifies how translation is carried out in terms of packet
translation. However, a particular implementation is at liberty to
adopt any internal structure as long as externally observable
behavior is identical.
4.1.1. Mixed IPv4/IPv6 Networks
In mixed networks, where there may be both IPv4 and IPv6 receivers,
two logical proxies are used. Each maintains membership state and
runs state machines in the address families of the receivers it is
proxying. Translation is applied to only one of them. This is
illustrated in Figure 2.
Upstream
+-----IPvX-----+
| |
+----+-----+ |
|Translator| |
+----+-----+ |
| |
+---+--------+ +-----+------+
| Proxy IPvY | | Proxy IPvX |
+-+-+-+-+-+--+ +-+-+-+-+-+--+
| | | | | | | | | |
Downstream(s) Downstream(s)
IPvX IPvX
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Figure 2: Mixed IPv4/IPv6 topology
4.2. Multicast Router
When implemented as part of a multicast router, the translation
function is logically situated on the downstream interfaces, as shown
in Figure 3. In this example, the router speaks PIM on an upstream
interface and IGMP/MLD on a downstream interface.
PIM
|
+--------+
| Router |
+--------+
|
+-------------+
| Translation |
+-------------+
|
IGMP/MLD
Figure 3: IGMP/MLD translator router topology
Note that the translation function can be completely virtual in this
case, as long as the externally observable behavior conforms to this
specification.
5. Signalling Translation
This section describes how to translate between IGMP and MLD.
5.1. IP Headers
5.1.1. Addresses
Destination addresses are translated as follows:
MLDv2 and IGMPv3: The destination address is a well-known address
and is translated as listed in Table 1.
MLDv1, IGMPv1, and IGMPv2: The destination address corresponds to
the address of the multicast group. The multicast group address
is mapped between IPv4 and IPv6 as described in
[I-D.boucadair-64-multicast-address-format].
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+--------------------------------------+------------+----------+
| Description | IPv4 | IPv6 |
+--------------------------------------+------------+----------+
| All nodes on link | 224.0.0.1 | ff02::1 |
| All routers on link | 224.0.0.2 | ff02::2 |
| All IGMP/MLD-capable routers on link | 224.0.0.22 | ff02::16 |
+--------------------------------------+------------+----------+
Table 1: IPv4/IPv6 Well-Known Multicast Address Equivalences
Source addresses are translated as follows:
IGMP to MLD: The source address is set to a link-local IPv6 address
assigned to the proxy's upstream interface.
MLD to IGMP: The source address is set to the IPv4 address assigned
to the proxy's upstream interface.
IGMP and MLD Reports having an unspecified source address (0.0.0.0 or
::) are handled differently. In MLD, they are dropped ([RFC3810]
section 5.2.13). In IGMP, they are accepted ([RFC3376] section
4.2.13). This means that translating 0.0.0.0 to :: and vice-versa
would change the router's behaviour: it would accept a message that
should have been dropped, and vice-versa. To eliminate this
ambiguity, the translator MUST drop IGMP and MLD reports having an
unspecified source address.
5.1.2. Router-Alert Option
IGMP messages are sent with a Router Alert IPv4 option [RFC2113]
while MLD message are sent with a Router Alert option in a Hop-By-Hop
IPv6 extension header [RFC2711]. The translator needs to convert
between these two. In particular, a Router Alert option MUST be sent
on output if and only if it was received on input. The value MUST be
set to zero unconditionally because the IPv4 and IPv6 value spaces
are not identical.
5.2. IGMP/MLD Translation
5.2.1. Message Type Equivalences
The IGMP/MLD messages to be handled by the translator belong to the
proxy's upstream interface, on which the proxy acts as a listener.
This means that translation will be applied to IGMP/MLD Reports and
Leave/Done messages sent from the proxy as well as to to IGMP/MLD
Queries received from routers.
Upon reception of an IGMP message with a type field containing one of
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the values listed in Table 2, the translator will intercept the
message and produce an equivalent MLDv2 message corresponding to an
ICMPv6 message with the listed type number in the same row. The
translator will perform the reverse operation upon reception of an
MLDv2 message.
+-----------------------+--------------------+
| IGMP type number | ICMPv6 type number |
+-----------------------+--------------------+
| 17 IGMPv1/v2/v3 Query | 130 MLDv1/v2 Query |
| 18 IGMPv1 Report | 131 MLDv1 Report |
| 22 IGMPv2 Report | 131 MLDv1 Report |
| 23 IGMPv2 Leave | 132 MLDv1 Done |
| 34 IGMPv3 Report | 143 MLDv2 Report |
+-----------------------+--------------------+
Table 2: IGMP/MLD Message Type Equivalences
5.2.2. The "Translated" Bit
Experience IPv6 transition in general and translation in particular
has shown that it is often useful, for various reasons, most often of
an operational nature, that can not necessarily be anticipated at the
time a specification gets written, to include a mechanism allowing
the identification of translated traffic.
This specification tries to anticipate that need by assigning a
reserved bit in both IGMPv3 and MLDv2 for such a purpose. When set
to 1, it indicates a message that has been translated according to
this specification at least once. When set to 0, it indicates that
no translation has been performed.
A translator conforming to this specification MUST set the Translated
bit to 1 on output. The bit is ignored on input by default, meaning
that a message could be translated twice or more. This will often be
undesirable, but is allowed by this specification.
In an IGMPv3 Query, bit number 64 is the Translated bit, as shown in
Figure 4.
In an IGMPv3 Report, bit number 32 is the Translated bit, as shown in
Figure 5.
In an MLDv2 Query, bit number 192 is the Translated bit, as shown in
Figure 6.
In an MLDv2 Report, bit number 32 is the Translated bit, as shown in
Figure 7.
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0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type = 0x11 | Max Resp Code | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Group Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|T|Resv |S| QRV | QQIC | Number of Sources (N) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Source Address [1] |
+- -+
| Source Address [2] |
+- . -+
. . .
. . .
+- -+
| Source Address [N] |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 4: "Translated" bit in an IGMPv3 Query (identified by the
letter T)
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0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type = 0x22 | Reserved | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|T| Reserved | Number of Group Records (M) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
. .
. Group Record [1] .
. .
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
. .
. Group Record [2] .
. .
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| . |
. . .
| . |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
. .
. Group Record [M] .
. .
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 5: "Translated" bit in an IGMPv3 Report (identified by the
letter T)
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0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type = 130 | Code | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Maximum Response Code | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
* *
| |
* Multicast Address *
| |
* *
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|T|Resv |S| QRV | QQIC | Number of Sources (N) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
* *
| |
* Source Address [1] *
| |
* *
| |
+- -+
| |
* *
| |
* Source Address [2] *
| |
* *
| |
+- . -+
. . .
. . .
+- -+
| |
* *
| |
* Source Address [N] *
| |
* *
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 6: "Translated" bit in an MLDv2 Query (identified by the
letter T)
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0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type = 143 | Reserved | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|T| Reserved |Nr of Mcast Address Records (M)|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
. .
. Multicast Address Record [1] .
. .
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
. .
. Multicast Address Record [2] .
. .
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| . |
. . .
| . |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
. .
. Multicast Address Record [M] .
. .
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 7: "Translated" bit in an MLDv2 Report (identified by the
letter T)
5.2.3. Maximum Response {Delay,Time}
IGMPv2 and IGMPv3 queries contain a field specifying the Maximum
Response Time (MRT), which is the maximum time allowed before sending
a Report, expressed in units of 1/10 seconds. Similarly, MLDv1 and
MLDv2 queries contain a field specifying the Maximum Response Delay
(MRD), expressed in units of milliseconds.
IGMPv2 (resp. MLDv1) encode the MRT (resp. MRD) value directly as a
binary integer. IGMPv3 (resp. MLDv2) allows a floating-point
encoding as well.
IGMPv2 and IGMPv3 uses an 8-bit field while MLDv1 and MLDv2 use a 16-
bit field.
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The conversion algorithm is as follows:
IGMPv2 to MLDv1: MRD = 100 * MRT
All values that can be represented in IGMPv2 can be equivalently
represented in MLDv1 without loss of precision.
IGMPv3 to MLDv2: MRD = 100 * MRT
All values that can be represented in IGMPv3 can be equivalently
represented in MLDv2 without loss of precision.
If MRT < 128, both MRT and MRD will be encoded as binary integers.
If 128 <= MRT < 336, MRT will be encoded as a floating-point value
while MRD will be encoded as a binary integer.
If 336 <= MRT, both MRT and MRD will be encoded as floating-point
values.
MLDv1 to IGMPv2: MRT = min(255, round(MRD / 100))
The MRD is divided by 100, rounded to the nearest integer, then
capped at 255 (the largest MRT value representable in IGMPv2).
There is both precision and range loss.
MLDv2 to IGMPv3: MRT = min(31744, round(MRD / 100))
The MRD is divided by 100, rounded to the nearest integer, then
capped at 31744 (the largest MRT value representable in IGMPv3).
There is both precision and range loss.
If MRD < 12800, both MRD and MRT will be encoded as binary
integers.
If 12800 <= MRD < 32768, MRD will be encoded as a binary integer
while MRT will be encoded as a floating-point value.
If 32768 <= MRD, both MRD and MRT will be encoded as binary
integers.
5.2.4. Multicast Group Address
The multicast group address is mapped between IPv4 and IPv6 as
described in [I-D.boucadair-64-multicast-address-format].
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5.2.5. Source Addresses
Source addresses, if any, are mapped as follows:
IGMP to MLD: IPv4 source addresses are mapped as described in
[RFC6052] section 2.2.
MLD to IGMP: An IPv4 address is extracted from an IPv6 source
address as described in [RFC6052] section 2.2. MLD messages
containing a source address outside the IPv4-Embedded IPv6 Prefix
are dropped unless there exists an applicable statically
configured mapping.
5.2.6. Additional and Auxiliary Data
All IGMPv3 and MLDv2 messages can contain Additional Data, as defined
in [RFC3376] sections 4.1.10 and 4.2.11 and [RFC3810] sections 5.1.12
and 5.2.11.
In addition, IGMPv3 and MLDv2 Reports can contain Auxiliary Data, as
defined in [RFC3376] section 4.2.10 and [RFC3810] section 5.2.10.
A translator MUST preserve Additional and Auxiliary Data. This is
accomplished by treating such data an an opaque blob and setting the
appropriate IPv4 or ICMPv6 length fields appropriately.
5.3. MTU Considerations
MTU issues should be handled at the application layer, not at the IP
layer. That is, the translator MUST split large Report messages into
smaller pieces that fit into an interface's MTU after translation, as
described in [RFC3810] section 5.2.15 and [RFC3376] section 4.2.16..
6. Data Transfer
Note: Should this section be removed? We could say nothing about
the data plane and instead focus exclusively on the signalling.
Thoughts?
The IGMP/MLD translator is configured either to translate the headers
of multicast packets or to encapsulate/decapsulate them. This
applies to regular multicast traffic, not to IGMP/MLD signalling.
Translation is performed according to [RFC6145], with the address
mapping specified in [I-D.boucadair-64-multicast-address-format].
IPv6 packets with a source or destination address outside MPREFIX64
are dropped unless there exists an applicable statically configured
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mapping.
Encapsulation/decapsulation might be preferable when joining two IPvX
islands across an IPvY network. Interfaces on which encapsulation/
decapsulation takes place are configured into the translator. When
encapsulating, the original packet is not modified. If it is an IPv6
packet, it gets encapsulated in an IPv4 packet, and vice-versa. The
addresses of the encapsulating packet are obtained by mapping those
of the original packet according to
[I-D.boucadair-64-multicast-address-format]. When decapsulating, the
original packet is obtained from the encapsulating packet's payload
and is forwarded as-is. Refer to [RFC2473] for details.
7. IANA Considerations
TODO
8. Security Considerations
TODO
9. Acknowledgements
The authors wish to thank the following people for their feedback:
Behcet Sarikaya, Dino Farinacci, Stig Venaas, and Tom Taylor.
10. Normative References
[I-D.boucadair-64-multicast-address-format]
Boucadair, M., Qin, J., Lee, Y., Venaas, S., Li, X., and
M. Xu, "IPv4-Embedded IPv6 Multicast Address Format",
draft-boucadair-64-multicast-address-format-00 (work in
progress), January 2012.
[RFC2113] Katz, D., "IP Router Alert Option", RFC 2113,
February 1997.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2473] Conta, A. and S. Deering, "Generic Packet Tunneling in
IPv6 Specification", RFC 2473, December 1998.
[RFC2711] Partridge, C. and A. Jackson, "IPv6 Router Alert Option",
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RFC 2711, October 1999.
[RFC3376] Cain, B., Deering, S., Kouvelas, I., Fenner, B., and A.
Thyagarajan, "Internet Group Management Protocol, Version
3", RFC 3376, October 2002.
[RFC3810] Vida, R. and L. Costa, "Multicast Listener Discovery
Version 2 (MLDv2) for IPv6", RFC 3810, June 2004.
[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.
[RFC6052] Bao, C., Huitema, C., Bagnulo, M., Boucadair, M., and X.
Li, "IPv6 Addressing of IPv4/IPv6 Translators", RFC 6052,
October 2010.
[RFC6145] Li, X., Bao, C., and F. Baker, "IP/ICMP Translation
Algorithm", RFC 6145, April 2011.
Authors' Addresses
Simon Perreault
Viagenie
246 Aberdeen
Quebec, QC G1R 2E1
Canada
Phone: +1 418 656 9254
Email: simon.perreault@viagenie.ca
URI: http://viagenie.ca
Tina Tsou
Huawei Technologies (USA)
2330 Central Expressway
Santa Clara, CA 95050
USA
Phone: +1 408 330 4424
Email: tina.tsou.zouting@huawei.com
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