INTERNET-DRAFT                                    Z. Albanna
draft-ietf-mboned-rfc3171bis-02.txt              K. Almeroth
Network Working Group                                          M. Cotton
Internet-Draft                                                     ICANN
Intended status: BCP                                            D. Meyer
Category                               Best Current Practice
Expires: December 26, 2008                                 June 24, 2008

         IANA Guidelines for IPv4 Multicast Address Assignments
                 <draft-ietf-mboned-rfc3171bis-02.txt>
                    draft-ietf-mboned-rfc3171bis-03

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   This document Memo

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Abstract

   This document is a product of the ABC working group.  Comments should
   be addressed to the authors, or obsoletes RFC 3171.  It provides guidance for the mailing list at

Copyright Notice

   Copyright (C) The Internet Society (2004). All Rights Reserved.

                                Abstract

   The
   Internet Assigned Numbers Authority is charged with allocating
   parameter values for fields (IANA) in protocols which have been designed,
   created or are maintained by the Internet Engineering Task Force.
   This document provides guidelines for the assignment of the assigning IPv4 IP
   multicast address space. addresses.

Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .   4  3
   2.  Terminology  . . . . . . . . . . . . . . . . . . . . . . . . .  3
   3.  Definition of Current Assignment Practice. Practice  . . . . . . . . . .   4
   3.  3
   4.  Local Network Control Block (224.0.0/24) . . . . . . . . . . .   5
    3.1.  4
     4.1.  Assignment Guidelines  . . . . . . . . . . . . . . . . . . .   5
   4.  4
   5.  Internetwork Control Block (224.0.1/24). (224.0.1/24)  . . . . . . . . . . .  5
    4.1.
     5.1.  Assignment Guidelines  . . . . . . . . . . . . . . . . . . .  5
   5.
   6.  AD-HOC Block (224.0.2/24 Blocks (including 224.0.2.0/24 - 224.0.255/24) . . . . . . . . 224.0.255.0/24)  . . .  5
    5.1.
     6.1.  Assignment Guidelines  . . . . . . . . . . . . . . . . . . .   6
   6.  5
   7.  SDP/SAP Block (224.2/16) . . . . . . . . . . . . . . . . . . .   6
    6.1.  5
     7.1.  Assignment Guidelines  . . . . . . . . . . . . . . . . . . .   6
   7.  5
   8.  Source Specific Multicast Block (232/8). (232/8)  . . . . . . . . . . .  6
    7.1.
     8.1.  Assignment Guidelines  . . . . . . . . . . . . . . . . . . .  6
   8.
   9.  GLOP Block (233/8) . . . . . . . . . . . . . . . . . . . . . .   7
    8.1.  6
     9.1.  Assignment Guidelines  . . . . . . . . . . . . . . . . . .  6
     9.2.  Extended AD-HOC  .   7
   9. Administratively Scoped Address Block (239/8). . . . . . . . .   7
    9.1. Assignment Guidelines . . . . . . . . . . . .  6
   10. Administratively Scoped Address Block (239/8)  . . . . . . .   7
     9.1.1. Relative Offsets .  6
     10.1. Assignment Guidelines  . . . . . . . . . . . . . . . . . .  7
   11. Application Form .   8
   10. Annual Review . . . . . . . . . . . . . . . . . . . . . .  7
     11.1. Size of assignments of IPv4 Multicast Addresses  . .   8
    10.1. Address Reclamation. . . .  7
   12. Annual Review  . . . . . . . . . . . . . . . .   8
   11. Usable IPv4 Multicast Addresses . . . . . . . .  8
     12.1. Address Reclamation  . . . . . . .   8
    11.1. IGMP-snooping switches . . . . . . . . . . . .  8
     12.2. Positive renewal . . . . . .   9
    11.2. Unusable Inter-domain Groups . . . . . . . . . . . . . . .   9
     11.2.1. Administratively Scoped Addresses . . . . . . . . . . .   9
     11.2.2. Special Use IPv4 Source Addresses . . . . . . . . . . .  10
   12.  8
   13. Use of IANA Reserved Addresses. . . . . . . . . . . . . . . .  10
   13. IANA Considerations . . . . . Addresses . . . . . . . . . . . . . . . .  10  8
   14. Acknowledgments . . IANA Considerations  . . . . . . . . . . . . . . . . . . . . .  10  8
   15. Security Considerations  . . . . . . . . . . . . . . . . . . .  11  8
   16. Normative References. . Acknowledgments  . . . . . . . . . . . . . . . . . . .  12
   17. Informative References. . . . .  9
   17. References . . . . . . . . . . . . . . .  12
   18. Author's Addresses. . . . . . . . . . . .  9
     17.1. Normative References . . . . . . . . . .  13
   19. Full Copyright Statement. . . . . . . . . .  9
     17.2. Informative References . . . . . . . . .  13
   20. Intellectual Property . . . . . . . . .  9
   Authors' Addresses . . . . . . . . . . .  14
   21. Acknowledgement . . . . . . . . . . . . . 10
   Intellectual Property and Copyright Statements . . . . . . . . . .  14 11

1.  Introduction

   The Internet Assigned Numbers Authority (IANA) (www.iana.org) is
   charged with allocating parameter values for fields in protocols
   which have been designed, created or are maintained by the Internet
   Engineering Task Force (IETF).  RFC 2780 [RFC2780] provides the IANA
   guidance in the assignment of parameters for fields in newly
   developed protocols.  This memo expands on section 4.4.2 of RFC 2780
   and attempts to codify existing IANA practice used in the assignment
   IPv4 multicast addresses.

   This document is a revision of RFC 3171 [RFC3171], which it
   obsoletes.  It should retain RFC 3171's status as BCP 51.  It also
   obsoletes RFC 3138 [RFC3138]."

   The terms "Specification Required", "Expert Review", "IESG Approval",
   "IETF Consensus", and "Standards Action", are used in this memo to
   refer to the processes described in [RFC2434].  The keywords MUST,
   MUST NOT, MAY, OPTIONAL, REQUIRED, RECOMMENDED, SHALL, SHALL NOT,
   SHOULD, SHOULD NOT are to be interpreted as defined in [RFC2119].

   In general, due to the relatively small size of the IPv4 multicast
   address space, further assignment of IPv4 multicast address space is
   recommended only in limited circumstances.  Specifically, the IANA
   should only assign addresses in those cases where the dynamic
   selection (SDP/SAP), GLOP, SSM or Administratively Scoped address
   spaces cannot be used.  The guidelines described below are reflected
   in <http://www.iana.org/numbers.html>.

2.  Terminology

   The key words "MUST"", "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in BCP 14, RFC 2119 [RFC 2119].

2.
   [RFC2119].

   The word "allocation" is defined as a block of addresses managed by a
   registry for the purpose of making assignments and allocations.  The
   word "assignment" is defined a block of addresses, or a single
   address, registered to an end-user for use on a specific network, or
   set of networks.

3.  Definition of Current Assignment Practice

   Unlike IPv4 unicast address assignment, where blocks of addresses are
   delegated to regional registries, Regional Internet Registries (RIRs), IPv4 multicast
   addresses are assigned directly by the IANA.  Current assignments registration
   groups appear as follows [IANA]:

224.0.0.0   - 224.0.0.255     (224.0.0/24)      224.0.0/24 Local Network Control Block

224.0.1.0   - 224.0.1.255     (224.0.1/24)      224.0.1/24 Internetwork Control Block

224.0.2.0   - 224.0.255.0      64769      AD-HOC Block (1)

224.1.0.0   - 224.1.255.255   (224.1/16)    224.1/16   RESERVED

224.2.0.0   - 224.2.255.255   (224.2/16)    224.2/16   SDP/SAP Block
   224.3.0.0

224.252.0.0 - 224.255.255.255  224.252/14 RESERVED

225.0.0.0   - 231.255.255.255  7 /8s      RESERVED

232.0.0.0   - 232.255.255.255 (232/8)  232/8     Source Specific Multicast Block

233.0.0.0   - 233.255.255.255 (233/8) 233.251.255.255  16515072   GLOP Block

233.252.0.0 - 233.255.255.255  233.252/14 AD-HOC Block (2)

234.0.0.0   - 238.255.255.255  5 /8s      RESERVED

239.0.0.0   - 239.255.255.255 (239/8)  239/8      Administratively Scoped Block

   The IANA generally assigns addresses from the Local Network Control,
   Internetwork Control, Control and AD-HOC blocks.  Assignment guidelines for
   each of these blocks, as well as for the Source Specific Multicast,
   GLOP and Administratively Scoped Blocks, are described below.

3.

4.  Local Network Control Block (224.0.0/24)

   Addresses in the Local Network Control block are used for protocol
   control traffic that is not forwarded off link.  Examples of this
   type of use include OSPFIGP All Routers (224.0.0.5) [RFC2328].

3.1.

4.1.  Assignment Guidelines

   Pursuant to section 4.4.2 of RFC 2780 [RFC2780], assignments from the Local
   Network Control block follow an Expert Review, IESG Approval or
   Standards Action process.  See IANA [IANA] for the current set of
   assignments.

4.

5.  Internetwork Control Block (224.0.1/24)

   Addresses in the Internetwork Control block are used for protocol
   control that must MAY be forwarded through the Internet.  Examples include
   224.0.1.1 (NTP [RFC2030]) and 224.0.1.68 (mdhcpdiscover [RFC2730]).

4.1.

5.1.  Assignment Guidelines

   Pursuant to section 4.4.2 of RFC 2780 [RFC2780], assignments from the
   Internetwork Control block follow an Expert Review, IESG Approval or
   Standards Action process.  See IANA [IANA] for the current set of
   assignments.

5.

6.  AD-HOC Block (224.0.2/24 Blocks (including 224.0.2.0/24 - 224.0.255/24) 224.0.255.0/24)

   Addresses in the AD-HOC block have blocks were traditionally been assigned used for
   assignments for those applications that don't fit in either the Local
   or Internetwork Control blocks.  These addresses are globally routed
   and are typically used by applications that require small blocks of
   addressing (e.g., less than a /24).

5.1. /24 ).  Future assignments of blocks of
   addresses that do not fit in the Local or Internetwork block will be
   made in the Extended block.

6.1.  Assignment Guidelines

   In general, the IANA SHOULD NOT assign addressing in the AD-HOC
   Block.  However, the IANA may MAY under special special circumstances, assign addressing
   addresses from this block.  Pursuant to section 4.4.2 of RFC
   2780 [RFC2780],
   assignments from the AD-HOC block follow an Expert Review, IESG
   Approval or Standards Action process.  See IANA [IANA] for the
   current set of assignments.

6.

7.  SDP/SAP Block (224.2/16)

   Addresses in the SDP/SAP block are used by applications that receive
   addresses through the Session Announcement Protocol [RFC2974] for use
   via applications like the session directory tool (such as SDR [SDR]).

6.1.

7.1.  Assignment Guidelines

   Since addresses in the SDP/SAP block are chosen randomly from the
   range of addresses not already in use [RFC2974], no IANA assignment
   policy is required.  Note that while no additional IANA assignment is
   required, addresses in the SDP/SAP block are explicitly for use by
   SDP/SAP and MUST NOT be used for other purposes.

7.

8.  Source Specific Multicast Block (232/8)

   The Source Specific Multicast (SSM) is an extension of IP Multicast
   in which traffic is forwarded to receivers from only those multicast
   sources for which the receivers have explicitly expressed interest,
   and is primarily targeted at one-to-many (broadcast) applications.
   Note that this block as initially assigned to the VMTP transient
   groups IANA [IANA].

7.1.

8.1.  Assignment Guidelines

   Because the SSM model essentially makes the entire multicast address
   space local to the host, no IANA assignment policy is required.
   Note, however, that while no additional IANA assignment is required,
   addresses in the SSM block are explicitly for use by SSM and MUST NOT
   be used for other purposes.

8.

9.  GLOP Block (233/8)

   Addresses in the GLOP block are globally scoped statically assigned
   addresses.  The assignment is made made, for a domain with 16 bit
   Autonomous System Number (ASN), by mapping a domain's autonomous the
   number, expressed in octets as X.Y, system number into the middle two
   octets of of the GLOP block, yielding an assignment of 233.X.Y.0/24.
   The mapping and assignment is defined in [RFC2770].

8.1. [RFC3180].  Domains with 32
   bit ASN should apply for space in the Extended AD-HOC block.

9.1.  Assignment Guidelines

   Because addresses in the GLOP block are algorithmically pre-assigned,
   no IANA assignment policy is required. In addition, RFC 3138

9.2.  Extended AD-HOC

   [RFC3138] delegates delegated assignment of the GLOP sub-block mapped by the
   RFC 1930
   [RFC1930] private AS space (233.252.0.0 - 233.255.255.255) to the Internet Routing Registries. Note that while no additional
   IANA
   RIRs.  This space was known as eGLOP.  The RIRs did not develop
   policies or the mechanisms for the assignment is required, addresses in of the GLOP  block are
   assigned eGLOP space and
   it is important to make this space available for use as defined in by network
   operators.  It is therefore appropriate to obsolete RFC 2770 3138 and MUST NOT be used
   classify this address range as available for
   other purposes.

9. AD-HOC assignment as per
   the guidelines in section 6.

10.  Administratively Scoped Address Block (239/8)

   Addresses in the Administratively Scoped Address block are for local
   use within a domain and are described in [RFC2365].

9.1.

10.1.  Assignment Guidelines

   Since addresses in this block are local to a domain, no IANA
   assignment policy is required.

9.1.1.

10.1.1.  Relative Offsets

   The relative offsets [RFC2365] are used to ensure that a service can
   be located independent of the extent of the enclosing scope (see RFC
   2770
   [RFC3180] for details).  Since there are only 256 such offsets, the
   IANA should only assign a relative offset to a protocol that provides
   an infrastructure supporting service.  Examples of such services
   include the Session Announcement Protocol [RFC2974].  Pursuant to
   section 4.4.2 of RFC 2780 [RFC2780], assignments of Relative Offsets follow an
   Expert Review, IESG Approval or Standards Action process.  See IANA
   [IANA] for the current set of assignments.

10.  Annual Review

   Given the dynamic nature of IPv4 multicast and its associated
   infrastructure, and the previously undocumented IPv4

11.  Application Form

   Requests for multicast address assignment guidelines, assignments can be submitted through
   the IANA should conduct an annual
   review of currently assigned addresses.

10.1.  Address Reclamation

   During application form on the review described above, addresses that were mis-assigned
   should, where possible, be reclaimed or reassigned.

   The IANA should also web site at:

   <http://www.iana.org/cgi-bin/multicast.pl>

   It is important to submit sufficient detail to allow the IESG
   designated expert to review assignments reclaim those addresses that
   are not the application.  If the details given in use on
   the global Internet (i.e, those applications which
   can use SSM, GLOP, or Administratively Scoped addressing, or request are not
   globally routed).

11.  Usable clear, or further information is needed, the IESG
   designated expert may request additional information before assigning
   an address.

11.1.  Size of assignments of IPv4 Multicast Addresses

   Multicast datagrams that match the criteria

   Occasionally, more than one multicast address is required.  In these
   cases multiple addresses are available in this section SHOULD
   NOT be used, even on local, unrouted subnetworks.

11.1.  IGMP-snooping switches

   RFC 1112 [RFC1112] describes the mapping Extended AD-HOC block.
   Where a very large number of IPv4 Multicast Group addresses to Ethernet MAC addresses, as follows:

     An IP host group address is mapped to an Ethernet multicast
     address by placing the low-order 23-bits of required, the IP address into assignment
   will be staged, with additional stages only being made after the low-order 23 bits
   complete use of the Ethernet multicast address
     01-00-5E-00-00-00 (hex).   Because there are 28 significant bits
     in an IP host group address, more than one host group address
     may map to initial assignment(s).

   A separate document describing the same Ethernet multicast address.

   Now, note that multicast group policy governing assignment of
   addresses in the 224.0.0.0/24 range
   are used for local subnetwork control (see section 3 above). Under
   the RFC 1112 mapping, this maps to the Ethernet multicast address
   range 01-00-5E-00-00-XX, where XX is 00 through FF. Ethernet frames
   within this range are always processed AD-HOC and Extended AD-HOC blocks will be developed
   and published.  The format, location and content has not yet been
   decided and so these will be documented in the control plane of many
   popular network devices, such as IGMP-snooping switches.

   Because a future version of this
   document.

12.  Annual Review

   Given the many-to-one mapping dynamic nature of IPv4 Multicast Group Addresses
   to Ethernet MAC addresses, it is possible to overwhelm multicast and its associated infra-
   structure, and the control
   plane previously undocumented IPv4 multicast address
   assignment guidelines, the IANA should conduct an annual review of network devices by sending to group
   currently assigned addresses.

12.1.  Address Reclamation

   During the review described above, addresses that map into
   the 01-00-5E-00-00-XX (hex) range.

   IGMP-snooping network devices must were mis-assigned
   should, where possible, be reclaimed or reassigned.

   The IANA should also flood these frames to all
   outgoing ports, so review assignments in the damage may extend to end systems AD-HOC, DIS Transient
   Groups, and routers.

11.2.  Unusable Inter-domain Groups ST Multicast datagrams Groups [RFC1190] blocks and reclaim those
   addresses that match the criteria are not in this section SHOULD
   NOT be routed between administrative domains.

11.2.1. use on the global Internet (i.e, those
   applications which can use SSM, GLOP, or Administratively Scoped Addresses

   RFC 2365 [RFC2365] defines 239.0.0.0/8 for use within an
   administrative domain.  As such, datagrams with group addresses that
   match 239.0.0.0/8 SHOULD NOT be passed between administrative
   domains.

11.2.2.  Special Use IPv4 Source Addresses

   RFC 1918 [RFC1918] defines certain ranges of IPv4 unicast addresses
   addressing, or are not globally routed).

12.2.  Positive renewal

   It is occasionally appropriate to make temporary assignments that can
   be used within renewed as necessary.  In cases where this happens the registrant
   needs to positively request an administrative domain.  Multicast
   datagrams are no exception extension to the rule that datagrams addressed
   within these ranges SHOULD NOT be passed between administrative
   domains. Examples include 127.0.0.0/8, which is widely used for
   internal host addressing, and is generally not valid on datagrams
   passed between hosts. 0.0.0.0/8 and 169.254.0.0/16 are also valid
   only in temporary assignment
   or the context of local links.  Such source addresses are assigned.  When the IANA has not
   valid for datagrams passed between networks[RFC330]. Finally
   192.0.2.0/24 is reserved received a request
   to renew the registration of a temporary assignment within 30 days of
   the expiry of the assignment it MUST be removed from the multicast
   registry.

   Addresses returned to the IANA when a temporary assignment ends MUST
   NOT be assigned for documentation and example code.
   [RFC3330].

12. at least one calendar year.

13.  Use of IANA Reserved Addresses

   Applications MUST NOT use addressing in the IANA reserved blocks.

13.

14.  IANA Considerations

   This document provides guidelines for the IANA to use in assigning
   IPv4 multicast addresses. It does not create any new namespaces for
   the is all about IANA to manage [RFC2434].

14.  Acknowledgments

   The authors would like to thank Scott Bradner, Randy Bush, John
   Meylor, Thomas Narten, Joe St. Sauver, and Beau Williamson for their
   constructive feedback and comments. Bill Nickless contributed the
   text in section 11 describing IPv4 multicast unusable group and
   source addresses. Considerations.

15.  Security Considerations

   The assignment guidelines described in this document do not alter the
   security properties of either the Any Source or Source Specific
   multicast service models.

16.  Acknowledgments

   The authors would like to thank Joe St. Sauver, John Meylor, Randy
   Bush, Thomas Narten, Marshall Eubanks, Zaid Albanna (co-author of
   RFC3171), Kevin Almeroth (co-author of RFC3171) and Leo Vegoda for
   their constructive feedback and comments.

17.  References

17.1.  Normative References

   [RFC1112]       Deering, S., "Host extensions for IP
                   multicasting", RFC 1112, August, 1989.

   [RFC1918]       Rekhter, Y. et. al., "Address Allocation for
                   Private Internets", RFC 1918, February, 1996.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March, March 1997.

17.2.  Informative References

   [IANA]     IANA, "IANA Matrix for Protocol Parameter Assignment/
              Registration Procedures",
              <http://www.iana.org/numbers.html>.

   [RFC1190]  Casner, S., Lynn, C., Park, P., Schroder, K., and C.
              Topolcic, "Experimental Internet Stream Protocol: Version
              2 (ST-II)", RFC 1190, October 1990.

   [RFC1930]  Hawkinson, J. and T. Bates, "Guidelines for creation,
              selection, and registration of an Autonomous System (AS)",
              BCP 6, RFC 1930, March 1996.

   [RFC2030]  Mills, D., "Simple Network Time Protocol (SNTP) Version 4
              for IPv4, IPv6 and OSI", RFC 2030, October 1996.

   [RFC2328]  Moy, J., "OSPF Version 2", STD 54, RFC 2328, April 1998.

   [RFC2365]  Meyer, D., "Administratively Scoped IP Multicast", BCP 23,
              RFC 2365, July 1998.

   [RFC3330]       IANA, "Special-Use IPv4 Addresses", RFC 3330,
                   September, 2002.

17.  Informative References

   [IANA]          http://www.iana.org/assignments/multicast-addresses

   [RFC2026]       Bradner, S., "The Internet Standards Process --
                   Revision 3", RFC 2026/BCP 9, October, 1996.

   [RFC2028]       Hovey, R. and S. Bradner, "The Organizations
                   Involved in the IETF Standards Process", RFC
                   2028/BCP 11, October, 1996.

   [RFC2434]  Narten, T., T. and H. Alvestrand, "Guidelines for Writing an
              IANA Considerations Section in RFCs",
                   RFC 2434/BCP BCP 26, RFC 2434,
              October 1998.

18.  Author's

   [RFC2730]  Hanna, S., Patel, B., and M. Shah, "Multicast Address
              Dynamic Client Allocation Protocol (MADCAP)", RFC 2730,
              December 1999.

   [RFC2780]  Bradner, S. and V. Paxson, "IANA Allocation Guidelines For
              Values In the Internet Protocol and Related Headers",
              BCP 37, RFC 2780, March 2000.

   [RFC2974]  Handley, M., Perkins, C., and E. Whelan, "Session
              Announcement Protocol", RFC 2974, October 2000.

   [RFC3138]  Meyer, D., "Extended Assignments in 233/8", RFC 3138,
              June 2001.

   [RFC3171]  Albanna, Z., Almeroth, K., Meyer, D., and M. Schipper,
              "IANA Guidelines for IPv4 Multicast Address Assignments",
              BCP 51, RFC 3171, August 2001.

   [RFC3180]  Meyer, D. and P. Lothberg, "GLOP Addressing in 233/8",
              BCP 53, RFC 3180, September 2001.

Authors' Addresses

   Zaid Albanna
   Email: zaid@juniper.net

   Kevin Almeroth

   Michelle Cotton
   Internet Corporation for Assigned Names and Numbers
   4676 Admiralty Way, Suite 330
   Marina del Rey  90292
   United States

   Phone: +310-823-9358
   Email: almeroth@cs.ucsb.edu michelle.cotton@icann.org
   URI:   http://www.iana.org/

   David Meyer

   Email: dmm@1-4-5.net

   Michelle S. Cotton
   Email: iana@iana.org

19.

Full Copyright Statement

   Copyright (C) The Internet Society (2004). IETF Trust (2008).

   This document is subject to the rights, licenses and restrictions
   contained in BCP 78 78, and except as set forth therein, the authors
   retain all their rights.

   This document and translations of it may be copied and furnished to
   others, and derivative works that comment on or otherwise explain it
   or assist in its implementation may be prepared, copied, published
   and distributed, in whole or in part, without restriction of any
   kind, provided that the above copyright notice and this paragraph are
   included on all such copies and derivative works. However, this
   document itself may not be modified in any way, such as by removing
   the copyright notice or references to the Internet Society or other
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21.  Acknowledgement

   Funding for the RFC Editor function is currently provided by the
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