INTERNET-DRAFT Z. Albanna draft-ietf-mboned-rfc3171bis-02.txt K. AlmerothNetwork Working Group M. Cotton Internet-Draft ICANN Intended status: BCP D. Meyer Category Best Current PracticeExpires: December 26, 2008 June 24, 2008 IANA Guidelines for IPv4 Multicast Address Assignments <draft-ietf-mboned-rfc3171bis-02.txt>draft-ietf-mboned-rfc3171bis-03 Status of this Document This documentMemo By submitting this Internet-Draft, each author represents that any applicable patent or other IPR claims of which he or she is an Internet-Draftaware have been or will be disclosed, and isany of which he or she becomes aware will be disclosed, in full conformanceaccordance with all provisions ofSection 106 of RFC2026.BCP 79. 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. 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." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txthttp://www.ietf.org/ietf/1id-abstracts.txt. The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. This Internet-Draft will expire on December 26, 2008. Abstract This document is a product of the ABC working group. Comments should be addressed to the authors, orobsoletes RFC 3171. It provides guidance for the mailing list at Copyright Notice Copyright (C) The Internet Society (2004). All Rights Reserved. Abstract TheInternet 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 theassigning IPv4 IPmulticast address space.addresses. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 43 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) . . . . . . . . . . . 5 126.96.36.199. Assignment Guidelines . . . . . . . . . . . . . . . . . . .5 5.6. AD-HOC Block (224.0.2/24Blocks (including 188.8.131.52/24 - 224.0.255/24) . . . . . . . .184.108.40.206/24) . . . 5 220.127.116.11. 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 18.104.22.168. 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 . . . . . . . . . . . . . . . . 108 14. Acknowledgments . .IANA Considerations . . . . . . . . . . . . . . . . . . . . . 108 15. Security Considerations . . . . . . . . . . . . . . . . . . . 118 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 . . . . . . . . . . 1411 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 assignmentsregistration groups appear as follows [IANA]: 22.214.171.124 - 126.96.36.199 (224.0.0/24)224.0.0/24 Local Network Control Block 188.8.131.52 - 184.108.40.206 (224.0.1/24)224.0.1/24 Internetwork Control Block 220.127.116.11 - 18.104.22.168 64769 AD-HOC Block (1) 22.214.171.124 - 126.96.36.199 (224.1/16)224.1/16 RESERVED 188.8.131.52 - 184.108.40.206 (224.2/16)224.2/16 SDP/SAP Block 224.3.0.022220.127.116.11 - 18.104.22.168 224.252/14 RESERVED 22.214.171.124 - 126.96.36.199 7 /8s RESERVED 188.8.131.52 - 184.108.40.206 (232/8)232/8 Source Specific Multicast Block 220.127.116.11 - 18.104.22.168 (233/8)22.214.171.124 16515072 GLOP Block 126.96.36.199 - 188.8.131.52 233.252/14 AD-HOC Block (2) 184.108.40.206 - 220.127.116.11 5 /8s RESERVED 18.104.22.168 - 22.214.171.124 (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 (126.96.36.199) [RFC2328]. 188.8.131.52. 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 mustMAY be forwarded through the Internet. Examples include 184.108.40.206 (NTP [RFC2030]) and 220.127.116.11 (mdhcpdiscover [RFC2730]). 18.104.22.168. 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 (224.0.2/24Blocks (including 22.214.171.124/24 - 224.0.255/24)126.96.36.199/24) Addresses in the AD-HOC block haveblocks were traditionally been assignedused 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 mayMAY under special specialcircumstances, assign addressingaddresses 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]). 188.8.131.52. 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]. 184.108.40.206. 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 mademade, 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 31389.2. Extended AD-HOC [RFC3138] delegatesdelegated assignment of the GLOP sub-block mapped by the RFC 1930[RFC1930] private AS space (220.127.116.11 - 18.104.22.168) to the Internet Routing Registries. Note that while no additional IANARIRs. This space was known as eGLOP. The RIRs did not develop policies or the mechanisms for the assignment is required, addresses inof the GLOP block are assignedeGLOP space and it is important to make this space available for use as defined inby network operators. It is therefore appropriate to obsolete RFC 27703138 and MUST NOT be usedclassify 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]. 22.214.171.124. Assignment Guidelines Since addresses in this block are local to a domain, no IANA assignment policy is required. 126.96.36.199.1.1. 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 IPv411. 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 Duringapplication form on the review described above, addresses that were mis-assigned should, where possible, be reclaimed or reassigned. TheIANA should alsoweb 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 notthe application. If the details given in use onthe global Internet (i.e, those applications which can use SSM, GLOP, or Administratively Scoped addressing, orrequest are not globally routed). 11. Usableclear, 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 criteriaOccasionally, 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] describesthe mappingExtended AD-HOC block. Where a very large number of IPv4 Multicast Groupaddresses to Ethernet MAC addresses, as follows: An IP host group addressis mapped to an Ethernet multicast address by placing the low-order 23-bits ofrequired, the IP address intoassignment will be staged, with additional stages only being made after the low-order 23 bitscomplete 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 toinitial assignment(s). A separate document describing the same Ethernet multicast address. Now, note that multicast grouppolicy governing assignment of addresses in the 188.8.131.52/24 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 processedAD-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. Becausea future version of this document. 12. Annual Review Given the many-to-one mappingdynamic nature of IPv4 Multicast Group Addresses to Ethernet MAC addresses, it is possible to overwhelmmulticast and its associated infra- structure, and the control planepreviously undocumented IPv4 multicast address assignment guidelines, the IANA should conduct an annual review of network devices by sending to groupcurrently 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 mustwere mis-assigned should, where possible, be reclaimed or reassigned. The IANA should also flood these frames to all outgoing ports, soreview assignments in the damage may extend to end systemsAD-HOC, DIS Transient Groups, and routers. 11.2. Unusable Inter-domain GroupsST Multicast datagramsGroups [RFC1190] blocks and reclaim those addresses that match the criteriaare 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 184.108.40.206/8 for use within an administrative domain. As such, datagrams with group addresses that match 220.127.116.11/8 SHOULD NOT be passed between administrative domains. 11.2.2. Special Use IPv4 Source Addresses RFC 1918 [RFC1918] defines certain ranges of IPv4 unicast addressesaddressing, or are not globally routed). 12.2. Positive renewal It is occasionally appropriate to make temporary assignments that can be used withinrenewed as necessary. In cases where this happens the registrant needs to positively request an administrative domain. Multicast datagrams are no exceptionextension 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 intemporary assignment or the context of local links. Such sourceaddresses areassigned. When the IANA has not valid for datagrams passed between networks[RFC330]. Finally 192.0.2.0/24 is reservedreceived 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 theis 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/BCPBCP 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: email@example.com Kevin AlmerothMichelle Cotton Internet Corporation for Assigned Names and Numbers 4676 Admiralty Way, Suite 330 Marina del Rey 90292 United States Phone: +310-823-9358 Email: firstname.lastname@example.org@icann.org URI: http://www.iana.org/ David Meyer Email: email@example.com Michelle S. Cotton Email: firstname.lastname@example.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 7878, and except as set forth therein, the authors retain all their rights. 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