draft-ietf-mboned-ssm232-04.txt   draft-ietf-mboned-ssm232-05.txt 
Network Working Group David Meyer INTERNET-DRAFT David Meyer
INTERNET DRAFT Sprint draft-ietf-mboned-ssm232-05.txt Rob Rockell
Rob Rockell
Sprint
Greg Shepherd Greg Shepherd
Procket Category Best Current Practice
Category Best Current Practices Expires: November 2003 May 2003
January, 2003
Source-Specific Protocol Independent Multicast in 232/8 Source-Specific Protocol Independent Multicast in 232/8
<draft-ietf-mboned-ssm232-05.txt>
<draft-ietf-mboned-ssm232-04.txt> Status of this Document
1. Status of this Memo
This document specifies an Internet Best Current Practices for the
Internet Community, and requests discussion and suggestions for
improvements. Distribution of this memo is unlimited.
This document is an Internet-Draft and is in full conformance with This document is an Internet-Draft and is in full conformance with
all provisions of Section 10 of RFC 2026. all provisions of Section 10 of RFC 2026.
Internet Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that other Task Force (IETF), its areas, and its working groups. Note that
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2. Copyright Notice This document is a product of the . Comments should be addressed to
the authors, or the mailing list at
Copyright Notice
Copyright (C) The Internet Society (2003). All Rights Reserved. Copyright (C) The Internet Society (2003). All Rights Reserved.
3. Abstract Abstract
IP Multicast group addresses in the 232/8 (232.0.0.0 to IP Multicast group addresses in the 232/8 (232.0.0.0 to
232.255.255.255) range are designated as source-specific multicast 232.255.255.255) range are designated as source-specific multicast
[SSM] destination addresses and are reserved for use by source- [SSM] destination addresses and are reserved for use by source-
specific applications and protocols [IANA]. This document defines specific applications and protocols [IANA]. This document defines
operational recommendations to ensure source-specific behavior within operational recommendations to ensure source-specific behavior within
the 232/8 range. the 232/8 range.
The keywords MUST, MUST NOT, MAY, OPTIONAL, REQUIRED, RECOMMENDED, The keywords MUST, MUST NOT, MAY, OPTIONAL, REQUIRED, RECOMMENDED,
SHALL, SHALL NOT, SHOULD, SHOULD NOT are to be interpreted as defined SHALL, SHALL NOT, SHOULD, SHOULD NOT are to be interpreted as defined
in RFC 2119 [RFC2119]. in RFC 2119 [RFC2119].
4. Introduction Table of Contents
Current PIM Sparse Mode [RFC2362] relies on the shared Rendezvous 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
Point (RP) tree to learn about active sources for a group and to 2. Operational practices in 232/8 . . . . . . . . . . . . . . . . 4
support group-generic (not source specific) data distribution. The IP 2.1. Preventing local sources from sending to shared tree. . . . 4
Multicast group address range 232/8 has been designated for source- 2.2. Preventing remote sources from being learned/joined via MSDP. 4
specific [SSM] applications and protocols [IANA] and SHOULD support 2.3. Preventing receivers from joining the shared tree . . . . . 5
source-only trees only, precluding the requirement of an RP and a 2.4. Preventing RP's as candidates for 232/8 . . . . . . . . . . 5
shared tree; active sources in the 232/8 range will be discovered out 3. Intellectual Property. . . . . . . . . . . . . . . . . . . . . 5
of band. PIM Sparse Mode Designated Routers (DR), with local 4. Acknowledgments. . . . . . . . . . . . . . . . . . . . . . . . 6
membership, are capable of joining the shortest path tree for the 5. Security Considerations. . . . . . . . . . . . . . . . . . . . 6
source directly using Source-Specific PIM [SSM]. 6. IANA Considerations. . . . . . . . . . . . . . . . . . . . . . 6
7. References . . . . . . . . . . . . . . . . . . . . . . . . . . 7
7.1. Normative References. . . . . . . . . . . . . . . . . . . . 7
7.2. Informative References. . . . . . . . . . . . . . . . . . . 7
8. Author's Addresses . . . . . . . . . . . . . . . . . . . . . . 7
9. Full Copyright Statement . . . . . . . . . . . . . . . . . . . 7
1. Introduction
Current PIM Sparse Mode (PIM-SM) [RFC2362] relies on the shared
Rendezvous Point (RP) tree to learn about active sources for a group
and to support group-generic (not source specific) data distribution.
The IP Multicast group address range 232/8 has been designated for
source-specific [SSM] applications and protocols [IANA] and SHOULD
support source-only trees only, precluding the requirement of an RP
and a shared tree; active sources in the 232/8 range will be
discovered out of band. PIM Sparse Mode Designated Routers (DR), with
local membership, are capable of joining the shortest path tree for
the source directly using Source-Specific PIM [SSM].
Operational best common practices in the 232/8 group address range Operational best common practices in the 232/8 group address range
are necessary to ensure shortest path source-only trees across are necessary to ensure shortest path source-only trees across
multiple domains in the Internet [SSM], and to prevent data from multiple domains in the Internet [SSM], and to prevent data from
sources sending to groups in the 232/8 range from arriving via shared sources sending to groups in the 232/8 range from arriving via shared
trees. This avoids unwanted data arrival, and allows several sources trees. This avoids unwanted data arrival, and allows several sources
to use the same group address without conflict at the receivers. to use the same group address without conflict at the receivers.
The operational practices SHOULD The operational practices SHOULD
skipping to change at page 3, line 4 skipping to change at page 4, line 12
trees. This avoids unwanted data arrival, and allows several sources trees. This avoids unwanted data arrival, and allows several sources
to use the same group address without conflict at the receivers. to use the same group address without conflict at the receivers.
The operational practices SHOULD The operational practices SHOULD
o Prevent local sources from sending to shared tree o Prevent local sources from sending to shared tree
o Prevent remote sources from being learned/joined via MSDP [MSDP] o Prevent remote sources from being learned/joined via MSDP [MSDP]
o Prevent receivers from joining the shared tree o Prevent receivers from joining the shared tree
o Prevent RP's as candidates for 232/8 o Prevent RP's as candidates for 232/8
5. Operational practices in 232/8 2. Operational practices in 232/8
5.1. Preventing local sources from sending to shared tree 2.1. Preventing local sources from sending to shared tree
Eliminating the use of shared trees for groups in 232/8, while Eliminating the use of shared trees for groups in 232/8, while
maintaining coexistence with PIM-SM, behavior of the RP and/or the DR maintaining coexistence with PIM-SM, behavior of the RP and/or the DR
needs to be modified. This can be accomplished by needs to be modified. This can be accomplished by
- preventing data for 232/8 groups from being sent encapsulated to - preventing data for 232/8 groups from being sent encapsulated to
the RP by the DR the RP by the DR
- preventing the RP from accepting registers for 232/8 groups from - preventing the RP from accepting registers for 232/8 groups from
the DR the DR
- preventing the RP from forwarding accepted data down (*,G) - preventing the RP from forwarding accepted data down (*,G)
tree for 232/8 groups tree for 232/8 groups
5.2. Preventing remote sources from being learned/joined via MSDP 2.2. Preventing remote sources from being learned/joined via MSDP
PIM-SS does not require active source announcements via MSDP. All PIM-SS does not require active source announcements via MSDP. All
source announcements are received out of band, the the last hop source announcements are received out of band, the the last hop
router is responsible for sending (S,G) joins directly to the source. router is responsible for sending (S,G) joins directly to the source.
To prevent propagation of SAs in the 232/8 range, an RP SHOULD To prevent propagation of SAs in the 232/8 range, an RP SHOULD
- never originate an SA for any 232/8 groups - never originate an SA for any 232/8 groups
- never accept or forward an SA for any 232/8 groups. - never accept or forward an SA for any 232/8 groups.
5.3. Preventing receivers from joining the shared tree 2.3. Preventing receivers from joining the shared tree
Local PIM domain practices need to be enforced to prevent local Local PIM domain practices need to be enforced to prevent local
receivers from joining the shared tree for 232/8 groups. This can be receivers from joining the shared tree for 232/8 groups. This can be
accomplished by accomplished by
- preventing DR from sending (*,G) joins for 232/8 groups - preventing DR from sending (*,G) joins for 232/8 groups
- preventing RP from accepting (*,G) join for 232/8 groups - preventing RP from accepting (*,G) join for 232/8 groups
However, within a local PIM domain, any last-hop router NOT However, within a local PIM domain, any last-hop router NOT
preventing (*,G) joins may trigger unwanted (*,G) state toward preventing (*,G) joins may trigger unwanted (*,G) state toward
the RP which intersects an existing (S,G) tree, allowing the the RP which intersects an existing (S,G) tree, allowing the
receiver on the shared tree to receive the data, breaking the receiver on the shared tree to receive the data, breaking the
source-specific [SSM] service model. It is therefore recommended source-specific [SSM] service model. It is therefore recommended
that ALL routers in the domain MUST reject AND never originate that ALL routers in the domain MUST reject AND never originate
(*,G) joins for 232/8 groups. (*,G) joins for 232/8 groups.
5.4. Preventing RP's as candidates for 232/8 In those cases in which an ISP is offering its customers (or
others) the use of the ISP's RP, the ISP SHOULD NOT allow (*,G)
joins in the 232/8 range.
Because PIM-SS does not require an RP, all RPs SHOULD NOT offer themˇ 2.4. Preventing RP's as candidates for 232/8
selves as candidates in the 232/8 range. This can be accomplished by
Because PIM-SS does not require an RP, all RPs SHOULD NOT offer
themselves as candidates in the 232/8 range. This can be accomplished
by
- preventing RP/BSR from announcing in the 232/8 range - preventing RP/BSR from announcing in the 232/8 range
- preventing ALL routers from accepting RP delegations in the - preventing ALL routers from accepting RP delegations in the
232/8 range 232/8 range
- precluding RP functionality on RP for the 232/8 range - precluding RP functionality on RP for the 232/8 range
6. Informative References 3. Intellectual Property
[IANA] http://www.iana.org 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. 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.
[RFC2119] S. Bradner, "Key words for use in RFCs to Indicate The IETF invites any interested party to bring to its attention any
Requirement Levels", RFC 2119, March, 1997. 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.
7. Normative References 4. Acknowledgments
[MSDP] D. Meyer and Bill Fenner (Editors), "The Multicast This document is the work of many people in the multicast community,
including (but not limited to) Dino Farinacci, John Meylor, John
Zwiebel, Tom Pusateri, Dave Thaler, Toerless Eckert, Leonard
Giuliano, Mike McBride, and Pekka Savola.
5. Security Considerations
This document describes operational practices that introduce no new
security issues to either PIM-SM or PIM-SSM.
6. IANA Considerations
This document creates a no new requirements on IANA namespaces
[RFC2434].
7. References
7.1. Normative References
[MSDP] Meyer, D. and B. Fenner (Editors), "The Multicast
Source Discovery Protocol (MSDP)", Source Discovery Protocol (MSDP)",
draft-ietf-msdp-spec-14.txt, November 2002. draft-ietf-msdp-spec-20.txt. Work in Progress.
[SSM] Holbrook, H., Cain, B., "Source-Specific Multicast", [SSM] Holbrook, H., and B. Cain,, "Source-Specific Multicast",
draft-ietf-ssm-arch-01.txt, November, 2002. draft-ietf-ssm-arch-03.txt. Work in Progress.
[RFC2362] D. Estrin, et. al., "Protocol Independent Multicast-Sparse [RFC2362] D. Estrin, et. al., "Protocol Independent Multicast-Sparse
Mode (PIM-SM): Protocol Specification", RFC 2362, June, Mode (PIM-SM): Protocol Specification", RFC 2362, June,
1998. 1998.
7.2. Informative References
[IANA] http://www.iana.org
[RFC2119] S. Bradner, "Key words for use in RFCs to Indicate
Requirement Levels", RFC 2119, March, 1997.
8. Author's Addresses 8. Author's Addresses
David Meyer David Meyer
Sprint Email: dmm@1-4-5.net
Email: dmm@sprint.net
Robert Rockell Robert Rockell
Sprint Sprint
Email: rrockell@sprint.net Email: rrockell@sprint.net
Greg Shepherd Greg Shepherd
Procket Procket
Email: shep@procket.com Email: shep@procket.com
9. Full Copyright Statement 9. Full Copyright Statement
Copyright (C) The Internet Society (2003). All Rights Reserved. Copyright (C) The Internet Society (2003). All Rights Reserved.
This document and translations of it may be copied and furnished to This document and translations of it may be copied and furnished to
others, and derivative works that comment on or otherwise explain it others, and derivative works that comment on or otherwise explain it
or assist in its implementation may be prepared, copied, published or assist in its implementation may be prepared, copied, published
and distributed, in whole or in part, without restriction of any and distributed, in whole or in part, without restriction of any
kind, provided that the above copyright notice and this paragraph are kind, provided that the above copyright notice and this paragraph are
included on all such copies and derivative works. However, this docˇ included on all such copies and derivative works. However, this
ument itself may not be modified in any way, such as by removing the document itself may not be modified in any way, such as by removing
copyright notice or references to the Internet Society or other the copyright notice or references to the Internet Society or other
Internet organizations, except as needed for the purpose of developˇ Internet organizations, except as needed for the purpose of
ing Internet standards in which case the procedures for copyrights developing Internet standards in which case the procedures for
defined in the Internet Standards process must be followed, or as copyrights defined in the Internet Standards process must be
required to translate it into languages other than English. followed, or as required to translate it into languages other than
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The limited permissions granted above are perpetual and will not be The limited permissions granted above are perpetual and will not be
revoked by the Internet Society or its successors or assigns. revoked by the Internet Society or its successors or assigns.
This document and the information contained herein is provided on an This document and the information contained herein is provided on an
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
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HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERˇ HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
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