Network Working Group                                           D. Meyer
Request for Comments: 3138                                        Sprint
Category: Informational                                        June 2001


                    Extended Assignments in 233/8

Status of this Memo

  This memo provides information for the Internet community.  It does
  not specify an Internet standard of any kind.  Distribution of this
  memo is unlimited.

Copyright Notice

  Copyright (C) The Internet Society (2001).  All Rights Reserved.

Abstract

  This memo provides describes the mapping of the GLOP addresses
  corresponding to the private AS space.

1. Introduction

  RFC 2770 [RFC2770] describes an experimental policy for use of the
  class D address space using 233/8.  The technique described there
  maps 16 bits of Autonomous System number (AS) into the middle two
  octets of 233/8 to yield a /24.  While this technique has been
  successful, the assignments are inefficient in those cases in which a
  /24 is too small or the user doesn't have its own AS.

  RFC 1930 [RFC1930] defines the private AS space to be 64512 through
  65535.  This memo expands on RFC 2770 to allow routing registries to
  assign multicast addresses from the GLOP space corresponding to the
  RFC 1930 private AS space.  This space will be referred to as the
  EGLOP (Extended GLOP) address space.

  This memo is a product of the Multicast Deployment Working Group
  (MBONED) in the Operations and Management Area of the Internet
  Engineering Task Force.  Submit comments to <[email protected]>
  or the authors.

  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 RFC 2119
  [RFC2119].



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2. Overview

  http://www.iana.org/assignments/multicast-addresses defines a
  mechanism for assignment of multicast addresses that are generally
  for use in network control applications.  It is envisioned that those
  addresses assigned from the EGLOP space (233.252.0.0 -
  233.255.255.255) will be used by applications that cannot use
  Administratively Scoped Addressing [RFC2365], GLOP Addressing
  [RFC2770], or Source Specific Multicast (Source Specific Multicast,
  or 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).

3. Assignment Criteria

  Globally scoped IPv4 multicast addresses in the EGLOP space are
  assigned by a Regional Registry (RIR).  An applicant MUST, as per
  [IANA], show that the request cannot be satisfied using
  Administratively Scoped addressing [RFC2365], GLOP addressing
  [RFC2770], or SSM.  The fine-grained assignment policy is left to the
  assigning RIR.

4. Security Considerations

  The assignment scheme described in this document does not effect the
  security properties of the the single source or any source multicast
  service models.

5. Acknowledgments

  Kurt Kayser, Mirjam Kuehne, Michelle Schipper and Randy Bush provided
  many insightful comments on earlier versions of this document.

6. Author's Address

  David Meyer
  Sprint
  12502 Sunrise Valley Dr
  Reston VA,  20191

  EMail: [email protected]









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7. References

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

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

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

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

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

  [RFC2770]       Meyer, D. and P. Lothberg, "GLOP Addressing in
                  233/8", RFC 2770, February 2000.

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


























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Full Copyright Statement

  Copyright (C) The Internet Society (2001).  All Rights Reserved.

  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
  Internet organizations, except as needed for the purpose of
  developing Internet standards in which case the procedures for
  copyrights defined in the Internet Standards process must be
  followed, or as required to translate it into languages other than
  English.

  The limited permissions granted above are perpetual and will not be
  revoked by the Internet Society or its successors or assigns.

  This document and the information contained herein is provided on an
  "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
  TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
  BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
  HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
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Acknowledgement

  Funding for the RFC Editor function is currently provided by the
  Internet Society.



















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