--- 1/draft-ietf-mboned-rfc3171bis-01.txt 2006-02-05 00:20:53.000000000 +0100 +++ 2/draft-ietf-mboned-rfc3171bis-02.txt 2006-02-05 00:20:54.000000000 +0100 @@ -1,20 +1,20 @@ INTERNET-DRAFT Z. Albanna -draft-ietf-mboned-rfc3171bis-01.txt K. Almeroth +draft-ietf-mboned-rfc3171bis-02.txt K. Almeroth M. Cotton D. Meyer Category Best Current Practice -Expires: July 2004 January 2004 +Expires: September 2004 March 2004 IANA Guidelines for IPv4 Multicast Address Assignments - + Status of this Document This document is an Internet-Draft and is in full conformance with all provisions of Section 10 of RFC2026. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet- Drafts. @@ -23,80 +23,87 @@ 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." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. - 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 RFC 2119 [RFC 2119]. - This document is a product of the ABC working group. Comments should be addressed to the authors, or 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 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 IPv4 IP multicast address space. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 2. Definition of Current Assignment Practice. . . . . . . . . . . 4 - 3. Local Network Control Block (224.0.0/24) . . . . . . . . . . . 4 + 3. Local Network Control Block (224.0.0/24) . . . . . . . . . . . 5 3.1. Assignment Guidelines . . . . . . . . . . . . . . . . . . . 5 4. Internetwork Control Block (224.0.1/24). . . . . . . . . . . . 5 4.1. Assignment Guidelines . . . . . . . . . . . . . . . . . . . 5 5. AD-HOC Block (224.0.2/24 - 224.0.255/24) . . . . . . . . . . . 5 - 5.1. Assignment Guidelines . . . . . . . . . . . . . . . . . . . 5 + 5.1. Assignment Guidelines . . . . . . . . . . . . . . . . . . . 6 6. SDP/SAP Block (224.2/16) . . . . . . . . . . . . . . . . . . . 6 6.1. Assignment Guidelines . . . . . . . . . . . . . . . . . . . 6 7. Source Specific Multicast Block (232/8). . . . . . . . . . . . 6 7.1. Assignment Guidelines . . . . . . . . . . . . . . . . . . . 6 8. GLOP Block (233/8) . . . . . . . . . . . . . . . . . . . . . . 7 8.1. Assignment Guidelines . . . . . . . . . . . . . . . . . . . 7 9. Administratively Scoped Address Block (239/8). . . . . . . . . 7 9.1. Assignment Guidelines . . . . . . . . . . . . . . . . . . . 7 - 9.1.1. Relative Offsets . . . . . . . . . . . . . . . . . . . . 7 + 9.1.1. Relative Offsets . . . . . . . . . . . . . . . . . . . . 8 10. Annual Review . . . . . . . . . . . . . . . . . . . . . . . . 8 10.1. Address Reclamation. . . . . . . . . . . . . . . . . . . . 8 - 11. Use of IANA Reserved Addresses. . . . . . . . . . . . . . . . 8 - 12. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8 - 13. Intellectual Property . . . . . . . . . . . . . . . . . . . . 9 - 14. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 9 - 15. Security Considerations . . . . . . . . . . . . . . . . . . . 10 - 16. Informative References. . . . . . . . . . . . . . . . . . . . 11 - 17. Author's Addresses. . . . . . . . . . . . . . . . . . . . . . 12 - 18. Full Copyright Statement. . . . . . . . . . . . . . . . . . . 12 + 11. Usable IPv4 Multicast Addresses . . . . . . . . . . . . . . . 8 + 11.1. IGMP-snooping switches . . . . . . . . . . . . . . . . . . 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. Use of IANA Reserved Addresses. . . . . . . . . . . . . . . . 10 + 13. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10 + 14. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 10 + 15. Security Considerations . . . . . . . . . . . . . . . . . . . 11 + 16. Normative References. . . . . . . . . . . . . . . . . . . . . 12 + 17. Informative References. . . . . . . . . . . . . . . . . . . . 12 + 18. Author's Addresses. . . . . . . . . . . . . . . . . . . . . . 13 + 19. Full Copyright Statement. . . . . . . . . . . . . . . . . . . 13 + 20. Intellectual Property . . . . . . . . . . . . . . . . . . . . 14 + 21. Acknowledgement . . . . . . . . . . . . . . . . . . . . . . . 14 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. + 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 RFC 2119 [RFC 2119]. + 2. Definition of Current Assignment Practice Unlike IPv4 unicast address assignment, where blocks of addresses are delegated to regional registries, IPv4 multicast addresses are assigned directly by the IANA. Current assignments appear as follows [IANA]: 224.0.0.0 - 224.0.0.255 (224.0.0/24) Local Network Control Block 224.0.1.0 - 224.0.1.255 (224.0.1/24) Internetwork Control Block 224.0.2.0 - 224.0.255.0 AD-HOC Block @@ -237,98 +244,154 @@ 10.1. Address Reclamation During the review described above, addresses that were mis-assigned should, where possible, be reclaimed or reassigned. The IANA should also review assignments reclaim those addresses that are not in use on the global Internet (i.e, those applications which can use SSM, GLOP, or Administratively Scoped addressing, or are not globally routed). -11. Use of IANA Reserved Addresses +11. Usable IPv4 Multicast Addresses - Applications MUST NOT use addressing in the IANA reserved blocks. + Multicast datagrams that match the criteria in this section SHOULD + NOT be used, even on local, unrouted subnetworks. -12. IANA Considerations +11.1. IGMP-snooping switches - This document provides guidelines for the IANA to use in assiging - IPv4 multicast addresses but does not create any new namespaces for - the IANA to manage. + RFC 1112 [RFC1112] describes the mapping of IPv4 Multicast Group + addresses to Ethernet MAC addresses, as follows: -13. Intellectual Property + An IP host group address is mapped to an Ethernet multicast + address by placing the low-order 23-bits of the IP address into + the low-order 23 bits 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 the same Ethernet multicast address. - The IETF takes no position regarding the validity or scope of any - intellectual property or other rights that might be claimed to - pertain to the implementation or use of the technology described in - this document or the extent to which any license under such rights - might or might not be available; neither does it represent that it - has made any effort to identify any such rights. Information on the - IETF's procedures with respect to rights in standards-track and - standards-related documentation can be found in BCP-11 [RFC2028]. - Copies of claims of rights made available for publication and any - assurances of licenses to be made available, or the result of an - attempt made to obtain a general license or permission for the use of - such proprietary rights by implementors or users of this - specification can be obtained from the IETF Secretariat. + Now, note that multicast group 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 in the control plane of many + popular network devices, such as IGMP-snooping switches. - The IETF invites any interested party to bring to its attention any - copyrights, patents or patent applications, or other proprietary - rights which may cover technology that may be required to practice - this standard. Please address the information to the IETF Executive - Director. + Because of the many-to-one mapping of IPv4 Multicast Group Addresses + to Ethernet MAC addresses, it is possible to overwhelm the control + plane of network devices by sending to group addresses that map into + the 01-00-5E-00-00-XX (hex) range. + + IGMP-snooping network devices must also flood these frames to all + outgoing ports, so the damage may extend to end systems and routers. + +11.2. Unusable Inter-domain Groups + + Multicast datagrams that match the criteria in this section SHOULD + NOT be routed between administrative domains. + +11.2.1. 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 + that can be used within an administrative domain. Multicast + datagrams are no exception 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 the context of local links. Such source addresses are not + valid for datagrams passed between networks[RFC330]. Finally + 192.0.2.0/24 is reserved for documentation and example code. + [RFC3330]. + +12. Use of IANA Reserved Addresses + + Applications MUST NOT use addressing in the IANA reserved blocks. + +13. 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 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. + constructive feedback and comments. Bill Nickless contributed the + text in section 11 describing IPv4 multicast unusable group and + source addresses. 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. Informative References +16. 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", RFC 2119, March, 1997. + [RFC2365] Meyer, D., "Administratively Scoped IP + Multicast", 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., and H. Alvestrand, "Guidelines for Writing an IANA Considerations Section in RFCs", RFC 2434/BCP 26, October 1998. -17. Author's Addresses +18. Author's Addresses Zaid Albanna Email: zaid@juniper.net Kevin Almeroth Email: almeroth@cs.ucsb.edu David Meyer Email: dmm@1-4-5.net Michelle S. Cotton Email: iana@iana.org -18. Full Copyright Statement +19. Full Copyright Statement - Copyright (C) The Internet Society (2004). All Rights Reserved. + Copyright (C) The Internet Society (2004). This document is subject + to the rights, licenses and restrictions contained in BCP 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 Internet organizations, except as needed for the purpose of @@ -339,10 +402,39 @@ 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 MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. + +20. Intellectual Property + + The IETF takes no position regarding the validity or scope of any + Intellectual Property Rights or other rights that might be claimed to + pertain to the implementation or use of the technology described in + this document or the extent to which any license under such rights + might or might not be available; nor does it represent that it has + made any independent effort to identify any such rights. Information + on the procedures with respect to rights in RFC documents can be + found in BCP 78 and BCP 79. + + Copies of IPR disclosures made to the IETF Secretariat and any + assurances of licenses to be made available, or the result of an + attempt made to obtain a general license or permission for the use of + such proprietary rights by implementers or users of this + specification can be obtained from the IETF on-line IPR repository at + http://www.ietf.org/ipr. + + The IETF invites any interested party to bring to its attention any + copyrights, patents or patent applications, or other proprietary + rights that may cover technology that may be required to implement + this standard. Please address the information to the IETF at ietf- + ipr@ietf.org. + +21. Acknowledgement + + Funding for the RFC Editor function is currently provided by the + Internet Society.