draft-ietf-mboned-64-multicast-address-format-03.txt   draft-ietf-mboned-64-multicast-address-format-04.txt 
MBONED Working Group M. Boucadair, Ed. MBONED Working Group M. Boucadair, Ed.
Internet-Draft France Telecom Internet-Draft France Telecom
Intended status: Standards Track J. Qin Updates: 3306 (if approved) J. Qin
Expires: February 11, 2013 Cisco Intended status: Standards Track Cisco
Y. Lee Expires: February 25, 2013 Y. Lee
Comcast Comcast
S. Venaas S. Venaas
Cisco Systems Cisco Systems
X. Li X. Li
CERNET Center/Tsinghua CERNET Center/Tsinghua
University University
M. Xu M. Xu
Tsinghua University Tsinghua University
August 10, 2012 August 24, 2012
IPv6 Multicast Address With Embedded IPv4 Multicast Address IPv6 Multicast Address With Embedded IPv4 Multicast Address
draft-ietf-mboned-64-multicast-address-format-03 draft-ietf-mboned-64-multicast-address-format-04
Abstract Abstract
This document reserves two IPv6 multicast prefixes to be used in the This document reserves one bit of the unicast prefix-based multicast
context of IPv4-IPv6 interconnection. The document specifies an IPv6 address for ASM and an IPv6 multicast prefix for SSM mode to be
algorithmic translation of an IPv6 multicast address to a used in the context of IPv4-IPv6 interconnection. The document
corresponding IPv4 multicast address, and vice versa. This specifies an algorithmic translation of an IPv6 multicast address to
a corresponding IPv4 multicast address, and vice versa. This
algorithmic translation can be used in both IPv4-IPv6 translation or algorithmic translation can be used in both IPv4-IPv6 translation or
encapsulation schemes. encapsulation schemes.
This document updates RFC 3306. One of the reserved bits defined in
RFC 3306 has now a meaning.
Requirements Language Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119]. document are to be interpreted as described in RFC 2119 [RFC2119].
Status of this Memo Status of this Memo
This Internet-Draft is submitted in full conformance with the This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79. provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/. Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on February 11, 2013.
This Internet-Draft will expire on February 25, 2013.
Copyright Notice Copyright Notice
Copyright (c) 2012 IETF Trust and the persons identified as the Copyright (c) 2012 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of (http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents publication of this document. Please review these documents
skipping to change at page 3, line 10 skipping to change at page 3, line 10
to this document. Code Components extracted from this document must to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. IPv4-Embedded IPv6 Multicast Prefix & Address . . . . . . . . 5 3. IPv4-Embedded IPv6 Multicast Prefix & Address . . . . . . . . 5
3.1. Reserving Dedicated Prefixes . . . . . . . . . . . . . . . 5 3.1. Design Considerations . . . . . . . . . . . . . . . . . . 5
3.2. IPv4-Embedded IPv6 Multicast Address . . . . . . . . . . . 6 3.2. ASM Mode . . . . . . . . . . . . . . . . . . . . . . . . . 6
3.3. Address Translation Algorithm . . . . . . . . . . . . . . 7 3.3. SSM Mode . . . . . . . . . . . . . . . . . . . . . . . . . 6
3.4. Textual Representation . . . . . . . . . . . . . . . . . . 7 3.4. IPv4-Embedded IPv6 Multicast Address . . . . . . . . . . . 7
3.5. Source IPv4 Address in the IPv6 Realm . . . . . . . . . . 7 3.5. Address Translation Algorithm . . . . . . . . . . . . . . 7
4. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 3.6. Textual Representation . . . . . . . . . . . . . . . . . . 8
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8 3.7. Source IPv4 Address in the IPv6 Realm . . . . . . . . . . 8
6. Security Considerations . . . . . . . . . . . . . . . . . . . 8 4. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 8 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 9
8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 8 6. Security Considerations . . . . . . . . . . . . . . . . . . . 9
8.1. Normative References . . . . . . . . . . . . . . . . . . . 8 7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 9
8.2. Informative References . . . . . . . . . . . . . . . . . . 9 8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 9
8.1. Normative References . . . . . . . . . . . . . . . . . . . 9
8.2. Informative References . . . . . . . . . . . . . . . . . . 10
Appendix A. Motivations . . . . . . . . . . . . . . . . . . . . . 10 Appendix A. Motivations . . . . . . . . . . . . . . . . . . . . . 10
A.1. Why an Address Format is Needed for Multicast A.1. Why an Address Format is Needed for Multicast
IPv4-IPv6 Interconnection? . . . . . . . . . . . . . . . . 10 IPv4-IPv6 Interconnection? . . . . . . . . . . . . . . . . 10
A.2. Why Identifying an IPv4-Embedded IPv6 Multicast A.2. Why Identifying an IPv4-Embedded IPv6 Multicast
Address is Required? . . . . . . . . . . . . . . . . . . . 10 Address is Required? . . . . . . . . . . . . . . . . . . . 11
A.3. Location of the IPv4 Address . . . . . . . . . . . . . . . 11 A.3. Location of the IPv4 Address . . . . . . . . . . . . . . . 12
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 11 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 12
1. Introduction 1. Introduction
Various solutions (e.g., [I-D.ietf-softwire-mesh-multicast], Various solutions (e.g., [I-D.ietf-softwire-mesh-multicast],
[I-D.ietf-softwire-dslite-multicast]) have been proposed to allow [I-D.ietf-softwire-dslite-multicast]) have been proposed to allow
access to IPv4 multicast content from hosts attached to IPv6-enabled access to IPv4 multicast content from hosts attached to IPv6-enabled
domains. Even if these solutions have distinct applicability scopes domains. Even if these solutions have distinct applicability scopes
(translation vs. encapsulation) and target different use cases, they (translation vs. encapsulation) and target different use cases, they
all make use of specific IPv6 multicast addresses to embed an IPv4 all make use of specific IPv6 multicast addresses to embed an IPv4
multicast address. Particularly, the IPv4-embedded IPv6 multicast multicast address. Particularly, the IPv4-Embedded IPv6 Multicast
address is used as a destination IPv6 address of multicast flows Address is used as a destination IPv6 address of multicast flows
received from an IPv4-enabled domain and injected by the IPv4-IPv6 received from an IPv4-enabled domain and injected by the IPv4-IPv6
Interconnection Function into an IPv6-enabled domain. It is also Interconnection Function into an IPv6-enabled domain. It is also
used to build an IPv6 multicast state (*, G6) or (S6, G6) used to build an IPv6 multicast state (*, G6) or (S6, G6)
corresponding to their (*, G4) or (S4, G4) IPv4 counter parts by the corresponding to their (*, G4) or (S4, G4) IPv4 counter parts by the
IPv4-IPv6 Interconnection Function. [I-D.ietf-mboned-v4v6-mcast-ps] IPv4-IPv6 Interconnection Function. [I-D.ietf-mboned-v4v6-mcast-ps]
provides more discussion about issues related to IPv4/IPv6 multicast. provides more discussion about issues related to IPv4/IPv6 multicast.
This document reserves two prefixes to be used to synthesize IPv4- This document reserves one bit of the unicast prefix-based multicast
embedded IPv6 multicast address. This document also defines how IPv6 address ([RFC3306]) for Any-Source Multicast (ASM) mode and an
IPv4-embedded IPv6 multicast addresses are constructed. Both IPv4- IPv6 multicast prefix for Source-Specific Multicast (SSM) mode to be
IPv6 translation or encapsulation schemes can make use of these used in the context of IPv4-IPv6 interconnection. This document also
prefixes. defines how IPv4-Embedded IPv6 Multicast Addresses are constructed.
Both IPv4-IPv6 translation and encapsulation schemes can make use of
Appendix A.1 enumerates the arguments in favor of reserving dedicated this specification.
prefixes Appendix A.2 discusses why identifying an IPv4-embedded IPv6
multicast address is needed.
This specification can be used in conjunction with other extensions This specification can be used in conjunction with other extensions
such as building unicast prefix-based multicast IPv6 address such as embedding the rendezvous point [RFC3956]. Unicast prefix-
[RFC3306] or embedding the rendezvous point [RFC3956]. These based and embedded-RP techniques are important tools to simplify IPv6
techniques are important tools to simplify IPv6 multicast multicast deployments. Indeed, unicast prefix-based IPv6 addressing
deployments. Indeed, unicast prefix-based IPv6 addressing is used in is used in many current IPv6 multicast deployments, and has also been
many current IPv6 multicast deployments, and has also been defined defined for IPv4, and is seen as a very useful technique. Also
for IPv4, and is seen as a very useful technique. Also embedded-RP embedded-RP is used in existing deployments.
is used in existing deployments.
This document is a companion document to [RFC6052] which focuses This document is a companion document to [RFC6052] which focuses
exclusively on IPv4-embedded IPv6 unicast addresses. exclusively on IPv4-embedded IPv6 unicast addresses.
2. Terminology 2. Terminology
This document makes use of the following terms: This document makes use of the following terms:
o IPv4-embedded IPv6 multicast address: denotes a multicast IPv6 o IPv4-Embedded IPv6 Multicast Address: denotes a multicast IPv6
address which includes in 32 bits an IPv4 address. address which includes in 32 bits an IPv4 address.
o Multicast Prefix64 (or MPREFIX64 for short) refers to an IPv6 o Multicast Prefix64 (or MPREFIX64 for short) refers to an IPv6
multicast prefix to be used to construct IPv4-embedded IPv6 multicast prefix to be used to construct IPv4-Embedded IPv6
multicast addresses. This prefix is used to build an IPv4- Multicast Addresses. This prefix is used to build an IPv4-
embedded IPv6 multicast address as defined in Section 3.3. Embedded IPv6 Multicast Address as defined in Section 3.5.
Section 3.3 specifies also how to extract an IPv4 address from an
IPv4-embedded IPv6 multicast address. Section 3.5 specifies also how to extract an IPv4 address from an
IPv4-Embedded IPv6 Multicast Address.
o ASM_MPREFIX64: denotes a multicast Prefix64 used in Any Source o ASM_MPREFIX64: denotes a multicast Prefix64 used in Any Source
Multicast (ASM) mode. Multicast (ASM) mode.
o SSM_MPREFIX64: denotes a multicast Prefix64 used in Source o SSM_MPREFIX64: denotes a multicast Prefix64 used in Source
Specific Multicast (SSM) mode. Specific Multicast (SSM) mode.
o IPv4-IPv6 Interconnection Function: refers to a function which is o IPv4-IPv6 Interconnection Function: refers to a function which is
enabled in a node interconnecting an IPv4-enabled domain with an enabled in a node interconnecting an IPv4-enabled domain with an
IPv6-enabled one. It can be located in various places of the IPv6-enabled one. It can be located in various places of the
multicast network. Particularly, in terms of multicast control multicast network. Particularly, in terms of multicast control
messages, it can be an IGMP/MLD Interworking Function or an IPv4- messages, it can be an IGMP/MLD Interworking Function or an IPv4-
IPv6 PIM Interworking Function. An IPv4-IPv6 Interconnection IPv6 PIM Interworking Function. An IPv4-IPv6 Interconnection
Function is configured with one or two MPREFIX64s. Function is configured with one or two MPREFIX64s.
3. IPv4-Embedded IPv6 Multicast Prefix & Address 3. IPv4-Embedded IPv6 Multicast Prefix & Address
3.1. Reserving Dedicated Prefixes 3.1. Design Considerations
The following constraints should be met when reserving dedicated The following constraints should be met when reserving dedicated
prefix(es) to be used for IPv4/IPv6 multicast interconnection: prefix(es) to be used for IPv4/IPv6 multicast interconnection:
1: Belong to ff3x::/32 and be compatible with unicast-based prefix 1: Belong to ff3x::/32 and be compatible with unicast-based prefix
[RFC3306] for SSM. Note that [RFC3306] suggests to set "plen" to [RFC3306] for SSM. Note that [RFC3306] suggests to set "plen" to
0 and "network-prefix" to 0. As such, any prefix in the 33-96 0 and "network-prefix" to 0. As such, any prefix in the 33-96
range can be convenient. Given [RFC4607] indicates future range can be convenient. Given [RFC4607] indicates future
specifications may allow a non-zero network prefix field, a /33 specifications may allow a non-zero network prefix field, a /33
would allow for future extensions but it has the drawback of would allow for future extensions but it has the drawback of
reserving a large block. A /96 would be adequate for the use reserving a large block. A /96 would be adequate for the use
cases already identified in [I-D.ietf-mboned-v4v6-mcast-ps]. In cases already identified in [I-D.ietf-mboned-v4v6-mcast-ps]. In
the event of any concrete extension, reserving additional the event of any concrete extension, reserving additional
prefixes may be considered. prefixes may be considered.
2: Be compatible with embedded-RP [RFC3956] and unicast-based prefix 2: Be compatible with embedded-RP [RFC3956] and unicast-based prefix
[RFC3306] for ASM. This results in a prefix length to be in the [RFC3306] for ASM. This results in reserving a bit in the 17-20
17-20 range. A /17 has the advantage of allowing for future range. Defining the 17-20 bits range to have a meaning and be
extensions but it may be seen as a waste of the multicast address used for IPv4/IPv6 transition has the advantage of allowing for
space. Consequently, a /20 is preferred. future extensions but it may be seen as a waste of the multicast
address space. Consequently, using one of the reserved bits (in
the range 17-20) from the unicast-based IPv6 multicast address
format [RFC3306] is preferred.
3: Avoid ff3x::4000:0001-ff3x::7fff:ffff which is reserved for IANA. Meeting (1) and (2) with the same reserved bit is not feasible
without modifying embedded-RP and unicast-based prefix
specifications; this option is avoided.
Meeting (1) and (2) with the same prefix is not feasible without As a consequence, this document proposes to reserve a multicast
modifying embedded-RP and unicast-based prefix specifications; this prefix for SSM and define one bit of the unicast prefix-based
option is avoided. multicast IPv6 address for ASM when embedding IPv4 multicast address
in an IPv6 multicast address.
As a consequence, two multicast prefixes are proposed to be used when 3.2. ASM Mode
embedding IPv4 address: one prefix for ASM and another one for the
SSM. This document reserves the following multicast prefixes to be
used in the context of IPv4/IPv6 multicast interconnection:
o ff3x:0:8000::/96 SSM range to embed an IPv4 multicast address in The format specified in Figure 1 uses some reserved bits defined in
the last 32 bits. [RFC3306] and [RFC3956]: the last of the 17-20 reserved bits now has
a meaning.
o ffxx:8000::/20 ASM range to embed an IPv4 multicast address in the | 8 | 4 | 4 | 3 |1| 76 | 32 |
last 32 bits. +--------+----+----+----+-+------------------------------+----------+
|11111111|flgs|scop|rsvd|M| sub-group-id |v4 address|
+--------+----+----+----+-+-----------------------------------------+
3.2. IPv4-Embedded IPv6 Multicast Address "rsvd" are reserved bits.
Figure 1: IPv4-Embedded IPv6 Multicast Address Format: ASM Mode
The description of the fields is as follows:
o "flgs" and "scop" fields are defined in [RFC3956].
o "rsvd": These 3 bits are reserved. The usage of these bits is the
same as defined in [RFC3306].
o M (20th bit position): When this bit is set to 1, it indicates
that a multicast IPv4 address is embedded in the low-order 32 bits
of the multicast IPv6 address.
o sub-group-id: This field is configurable according to local
policies (e.g., enable embedded-RP) of the entity managing the
IPv4-IPv6 Interconnection Function. This field MUST follow the
recommendations specified in [RFC3306] if unicast-based prefix is
used or the recommendations specified in [RFC3956] if embedded-RP
is used. The default value is all zeros.
o The low-order 32 bits MUST include an IPv4 multicast address when
the M-bit is set to 1. The enclosed IPv4 multicast address SHOULD
NOT be in 232/8 range.
3.3. SSM Mode
For SSM mode, and given what is discussed in Section 3.1, the
following IPv6 prefix to embed IPv4 multicast addresses is reserved:
o ff3x:0:8000::/96 ('x' is any valid scope).
3.4. IPv4-Embedded IPv6 Multicast Address
For the delivery of the IPv4-IPv6 multicast interconnection services, For the delivery of the IPv4-IPv6 multicast interconnection services,
a dedicated multicast prefix denoted as MPREFIX64 should be a dedicated multicast prefix denoted as MPREFIX64 should be
provisioned (e.g., using NETCONF or provisioned (e.g., using NETCONF or
[I-D.ietf-softwire-multicast-prefix-option]) to any function [I-D.ietf-softwire-multicast-prefix-option]) to any function
requiring to build an IPv4-embedded IPv6 multicast address based on requiring to build an IPv4-Embedded IPv6 Multicast Address based on
an IPv4 multicast address. MPREFIX64 can be of ASM or SSM type. an IPv4 multicast address. MPREFIX64 can be of ASM or SSM type.
When both modes are used, two prefixes are required to be When both modes are used, two prefixes are required to be
provisioned. provisioned.
The length of MPREFIX64 MUST be /96. MPREFIX64 should belong to The length of MPREFIX64 MUST be /96. For SSM, MPREFIX64 MUST be
ffxx:8000::/20 for ASM mode and ff3x:0:8000::/96 for the SSM mode. equal to ff3x:0:8000::/96. For the ASM mode, MPREFIX64 MUST have the
M-bit set to 1. Furthermore, the format of the ASM_MPREFIX64 should
For the ASM mode, the format of the MPREFIX64 should follow what is follow what is specified in [RFC3306] and [RFC3956] if corresponding
specified in [RFC3306] and [RFC3956] if corresponding mechanisms are mechanisms are used. If not, bits 21-96 can be set to any value.
used. If not, bits 21-96 can be set to any value.
Figure 1 shows how to build an IPv4-embedded IPv6 multicast address Figure 2 shows how to build an IPv4-Embedded IPv6 Multicast Address
using a configured MPREFIX64 and an IPv4 multicast address. The low- using a configured MPREFIX64 and an IPv4 multicast address. The low-
order 32 bits MUST include an IPv4 multicast address. The enclosed order 32 bits MUST include an IPv4 multicast address. The enclosed
IPv4 multicast address SHOULD NOT be in 232/8 range if an IPv4 multicast address SHOULD NOT be in 232/8 range if an
ASM_PREFIX64 is configured. The enclosed IPv4 multicast address ASM_PREFIX64 is configured. The enclosed IPv4 multicast address
SHOULD be in 232/8 range if an SSM_PREFIX64 is configured. SHOULD be in 232/8 range if an SSM_PREFIX64 is configured.
Embedding an IPv4 multicast address in the last 32 bits does not Embedding an IPv4 multicast address in the last 32 bits does not
conflict with the Group IDs assigned by IANA (i.e., 0x00000001 to conflict with the Group IDs assigned by IANA (i.e., 0x00000001 to
0x3FFFFFFF [RFC3307]). 0x3FFFFFFF [RFC3307]).
When several MPREFIX64 are available, it is RECOMMENDED to use the When several MPREFIX64 are available, it is RECOMMENDED to use the
MPREFIX64 which preserve the scope of the IPv4 multicast address. MPREFIX64 which preserve the scope of the IPv4 multicast address.
| 96 | 32 | | 96 | 32 |
+------------------------------------------------------+----------+ +------------------------------------------------------+----------+
| MPREFIX64 |v4 address| | MPREFIX64 |v4 address|
+------------------------------------------------------+----------+ +------------------------------------------------------+----------+
Figure 1: IPv4-Embedded IPv6 Multicast Address Format Figure 2: IPv4-Embedded IPv6 Multicast Address Format
3.3. Address Translation Algorithm 3.5. Address Translation Algorithm
IPv4-embedded IPv6 multicast addresses are composed according to the IPv4-Embedded IPv6 Multicast Addresses are composed according to the
following algorithm: following algorithm:
o Concatenate the MPREFIX64 and the 32 bits of the IPv4 address to o Concatenate the MPREFIX64 and the 32 bits of the IPv4 address to
obtain a 128-bit address. obtain a 128-bit address.
The IPv4 multicast addresses are extracted from the IPv4-embedded The IPv4 multicast addresses are extracted from the IPv4-Embedded
IPv6 multicast addresses according to the following algorithm: IPv6 Multicast Addresses according to the following algorithm:
o If the multicast address belongs to ff3x:0:8000::/96 or ffxx: o If the multicast address has the 20th bit set to 1 or it matches
8000::/20, extract the last 32 bits of the IPv6 multicast address. ff3x:0:8000::/96 or a preconfigured MPREFIX64, extract the last 32
bits of the IPv6 multicast address.
3.4. Textual Representation 3.6. Textual Representation
The embedded IPv4 address in an IPv6 multicast address is included in The embedded IPv4 address in an IPv6 multicast address is included in
the last 32 bits; therefore dotted decimal notation can be used. the last 32 bits; therefore dotted decimal notation can be used.
3.5. Source IPv4 Address in the IPv6 Realm 3.7. Source IPv4 Address in the IPv6 Realm
An IPv4 source is represented in the IPv6 realm with its IPv4- An IPv4 source is represented in the IPv6 realm with its IPv4-
converted IPv6 address [RFC6052]. converted IPv6 address [RFC6052].
4. Examples 4. Examples
Figure 2 provides an example of ASM IPv4-Embedded IPv6 Address while Figure 3 provides some examples of ASM IPv4-Embedded IPv6 Address
Figure 3 provides an example of SSM IPv4-Embedded IPv6 Address. while Figure 4 provides an example of SSM IPv4-Embedded IPv6 Address.
IPv4 multicast addresses used in the examples are derived from the IPv4 multicast addresses used in the examples are derived from the
IPv4 multicast block reserved for documentation in IPv4 multicast block reserved for documentation in [RFC6676].
[I-D.ietf-mboned-mcaddrdoc].
+---------------------+--------------+----------------------------+ +----------------------+--------------+-----------------------------+
| MPREFIX64 | IPv4 address | IPv4-embedded IPv6 address | | MPREFIX64 | IPv4 address | IPv4-Embedded IPv6 Address |
+---------------------+--------------+----------------------------+ +----------------------+--------------+-----------------------------+
| ffxx:8000:0:abc::/96| 233.252.0.1 |ffxx:8000:0:abc::233.252.0.1| | ff3x:z000:0:abc::/96 | 233.252.0.1 |ff3x:z000:0:abc::233.252.0.1 |
+---------------------+--------------+----------------------------+ | ff7x:z000:0:abc::/96 | 233.252.0.2 |ff7x:z000:0:abc::233.252.0.2 |
+----------------------+--------------+-----------------------------+
where:
"x" is any valid scope
"z" is any 4 bits where the last bit is set (e.g., 1, 3, 7, ...)
Figure 2: Example of ASM IPv4-embedded IPv6 address Figure 3: Example of ASM IPv4-embedded IPv6 address
+---------------------+--------------+----------------------------+ +---------------------+--------------+----------------------------+
| MPREFIX64 | IPv4 address | IPv4-embedded IPv6 address | | MPREFIX64 | IPv4 address | IPv4-Embedded IPv6 Address |
+---------------------+--------------+----------------------------+ +---------------------+--------------+----------------------------+
| ff3x:0:8000::/96 | 233.252.0.5 | ff3x:0:8000::233.252.0.5 | | ff3x:0:8000::/96 | 233.252.0.5 | ff3x:0:8000::233.252.0.5 |
+---------------------+--------------+----------------------------+ +---------------------+--------------+----------------------------+
Figure 3: Example of SSM IPv4-embedded IPv6 address Figure 4: Example of SSM IPv4-embedded IPv6 address
5. IANA Considerations 5. IANA Considerations
Authors of this document request to reserve: This document requests IANA to reserve:
o ff3x:0:8000::/96 SSM range to embed an IPv4 multicast address in o ff3x:0:8000::/96 SSM range to embed an IPv4 multicast address in
the last 32 bits. the last 32 bits.
o ffxx:8000::/20 ASM range to embed an IPv4 multicast address in the
last 32 bits.
6. Security Considerations 6. Security Considerations
This document defines an algorithmic translation of an IPv6 multicast This document defines an algorithmic translation of an IPv6 multicast
address into an IPv4 multicast address, and vice versa. The security address into an IPv4 multicast address, and vice versa. The security
considerations discussed in [RFC6052] are to be taken into considerations discussed in [RFC6052] are to be taken into
consideration. consideration.
7. Acknowledgements 7. Acknowledgements
Many thanks to R. Bonica, B. Sarikaya, P. Savola, T. Tsou and C. Many thanks to R. Bonica, B. Sarikaya, P. Savola, T. Tsou, C.
Bormann for their comments and review. Bormann, T. Chown and P. Koch for their comments and review.
8. References 8. References
8.1. Normative References 8.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997. Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC3306] Haberman, B. and D. Thaler, "Unicast-Prefix-based IPv6 [RFC3306] Haberman, B. and D. Thaler, "Unicast-Prefix-based IPv6
Multicast Addresses", RFC 3306, August 2002. Multicast Addresses", RFC 3306, August 2002.
skipping to change at page 9, line 30 skipping to change at page 10, line 13
October 2010. October 2010.
8.2. Informative References 8.2. Informative References
[I-D.ietf-behave-nat64-learn-analysis] [I-D.ietf-behave-nat64-learn-analysis]
Korhonen, J. and T. Savolainen, "Analysis of solution Korhonen, J. and T. Savolainen, "Analysis of solution
proposals for hosts to learn NAT64 prefix", proposals for hosts to learn NAT64 prefix",
draft-ietf-behave-nat64-learn-analysis-03 (work in draft-ietf-behave-nat64-learn-analysis-03 (work in
progress), March 2012. progress), March 2012.
[I-D.ietf-mboned-mcaddrdoc]
Venaas, S., Parekh, R., Velde, G., Chown, T., and M.
Eubanks, "Multicast Addresses for Documentation",
draft-ietf-mboned-mcaddrdoc-04 (work in progress),
May 2012.
[I-D.ietf-mboned-v4v6-mcast-ps] [I-D.ietf-mboned-v4v6-mcast-ps]
Jacquenet, C., Boucadair, M., Lee, Y., Qin, J., Tsou, T., Jacquenet, C., Boucadair, M., Lee, Y., Qin, J., Tsou, T.,
and Q. Sun, "IPv4-IPv6 Multicast: Problem Statement and and Q. Sun, "IPv4-IPv6 Multicast: Problem Statement and
Use Cases", draft-ietf-mboned-v4v6-mcast-ps-00 (work in Use Cases", draft-ietf-mboned-v4v6-mcast-ps-00 (work in
progress), May 2012. progress), May 2012.
[I-D.ietf-softwire-dslite-multicast] [I-D.ietf-softwire-dslite-multicast]
Qin, J., Boucadair, M., Jacquenet, C., Lee, Y., and Q. Qin, J., Boucadair, M., Jacquenet, C., Lee, Y., and Q.
Wang, "Multicast Extensions to DS-Lite Technique in Wang, "Delivery of IPv4 Multicast Services to IPv4 Clients
Broadband Deployments", over an IPv6 Multicast Network",
draft-ietf-softwire-dslite-multicast-02 (work in draft-ietf-softwire-dslite-multicast-03 (work in
progress), May 2012. progress), August 2012.
[I-D.ietf-softwire-mesh-multicast] [I-D.ietf-softwire-mesh-multicast]
Xu, M., Cui, Y., Wu, J., Yang, S., Metz, C., and G. Xu, M., Cui, Y., Wu, J., Yang, S., Metz, C., and G.
Shepherd, "Softwire Mesh Multicast", Shepherd, "Softwire Mesh Multicast",
draft-ietf-softwire-mesh-multicast-03 (work in progress), draft-ietf-softwire-mesh-multicast-03 (work in progress),
July 2012. July 2012.
[I-D.ietf-softwire-multicast-prefix-option] [I-D.ietf-softwire-multicast-prefix-option]
Boucadair, M., Qin, J., Tsou, T., and X. Deng, "DHCPv6 Boucadair, M., Qin, J., Tsou, T., and X. Deng, "DHCPv6
Option for IPv4-Embedded Multicast and Unicast IPv6 Option for IPv4-Embedded Multicast and Unicast IPv6
Prefixes", draft-ietf-softwire-multicast-prefix-option-01 Prefixes", draft-ietf-softwire-multicast-prefix-option-01
(work in progress), August 2012. (work in progress), August 2012.
[RFC4566] Handley, M., Jacobson, V., and C. Perkins, "SDP: Session [RFC4566] Handley, M., Jacobson, V., and C. Perkins, "SDP: Session
Description Protocol", RFC 4566, July 2006. Description Protocol", RFC 4566, July 2006.
[RFC6676] Venaas, S., Parekh, R., Van de Velde, G., Chown, T., and
M. Eubanks, "Multicast Addresses for Documentation",
RFC 6676, August 2012.
Appendix A. Motivations Appendix A. Motivations
A.1. Why an Address Format is Needed for Multicast IPv4-IPv6 A.1. Why an Address Format is Needed for Multicast IPv4-IPv6
Interconnection? Interconnection?
Arguments why an IPv6 address format is needed to embed multicast Arguments why an IPv6 address format is needed to embed multicast
IPv4 address are quite similar to those of [RFC6052]. Concretely, IPv4 address are quite similar to those of [RFC6052]. Concretely,
the definition of a multicast address format embedding a multicast the definition of a multicast address format embedding a multicast
IPv4 address allows: IPv4 address allows:
skipping to change at page 11, line 23 skipping to change at page 12, line 6
located downstream the receiver. As such, the ALG does not know located downstream the receiver. As such, the ALG does not know
in advance whether the receiver is dual-stack or IPv6-only. The in advance whether the receiver is dual-stack or IPv6-only. The
ALG may be tuned to insert both the original IPv4 address and ALG may be tuned to insert both the original IPv4 address and
corresponding IPv6 multicast address. If a dedicated prefix is corresponding IPv6 multicast address. If a dedicated prefix is
not used, a dual-stack receiver may prefer to use the IPv6 not used, a dual-stack receiver may prefer to use the IPv6
address to receive the multicast content. This address selection address to receive the multicast content. This address selection
would require multicast flows to cross an IPv4-IPv6 would require multicast flows to cross an IPv4-IPv6
interconnection function. interconnection function.
2. In order to avoid involving an ALG in the path, an IPv4-only 2. In order to avoid involving an ALG in the path, an IPv4-only
source can advertise both its IPv4 address and IPv4-embedded IPv6 source can advertise both its IPv4 address and IPv4-Embedded IPv6
multicast address. If a dedicated prefix is not reserved, a Multicast Address. If a dedicated prefix is not reserved, a
dual-stack receiver may prefer to use the IPv6 address to receive dual-stack receiver may prefer to use the IPv6 address to receive
the multicast content. This address selection would require the multicast content. This address selection would require
multicast flows to cross an IPv4-IPv6 interconnection function. multicast flows to cross an IPv4-IPv6 interconnection function.
Reserving dedicated IPv6 multicast prefixes for IPv4-IPv6 Reserving dedicated IPv6 multicast prefixes for IPv4-IPv6
interconnection purposes mitigates the issues discussed in interconnection purposes mitigates the issues discussed in
[I-D.ietf-behave-nat64-learn-analysis] in a multicast context. [I-D.ietf-behave-nat64-learn-analysis] in a multicast context.
A.3. Location of the IPv4 Address A.3. Location of the IPv4 Address
 End of changes. 44 change blocks. 
114 lines changed or deleted 151 lines changed or added

This html diff was produced by rfcdiff 1.41. The latest version is available from http://tools.ietf.org/tools/rfcdiff/