Deprecating Any-Source Multicast (ASM) for Interdomain Multicast
RFC 8815
Document | Type |
RFC - Best Current Practice
(August 2020; No errata)
Also known as BCP 229
|
|
---|---|---|---|
Authors | Mikael Abrahamsson , Tim Chown , Leonard Giuliano , Toerless Eckert | ||
Last updated | 2020-08-27 | ||
Replaces | draft-acg-mboned-deprecate-interdomain-asm | ||
Stream | IETF | ||
Formats | plain text html xml pdf htmlized bibtex | ||
Reviews | |||
Stream | WG state | Submitted to IESG for Publication | |
Document shepherd | Colin Doyle | ||
Shepherd write-up | Show (last changed 2019-11-01) | ||
IESG | IESG state | RFC 8815 (Best Current Practice) | |
Consensus Boilerplate | Yes | ||
Telechat date | |||
Responsible AD | Warren Kumari | ||
Send notices to | Colin Doyle <cdoyle@juniper.net> | ||
IANA | IANA review state | IANA OK - No Actions Needed | |
IANA action state | No IANA Actions |
Internet Engineering Task Force (IETF) M. Abrahamsson Request for Comments: 8815 BCP: 229 T. Chown Category: Best Current Practice Jisc ISSN: 2070-1721 L. Giuliano Juniper Networks, Inc. T. Eckert Futurewei Technologies Inc. August 2020 Deprecating Any-Source Multicast (ASM) for Interdomain Multicast Abstract This document recommends deprecation of the use of Any-Source Multicast (ASM) for interdomain multicast. It recommends the use of Source-Specific Multicast (SSM) for interdomain multicast applications and recommends that hosts and routers in these deployments fully support SSM. The recommendations in this document do not preclude the continued use of ASM within a single organization or domain and are especially easy to adopt in existing deployments of intradomain ASM using PIM Sparse Mode (PIM-SM). Status of This Memo This memo documents an Internet Best Current Practice. This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on BCPs is available in Section 2 of RFC 7841. Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at https://www.rfc-editor.org/info/rfc8815. Copyright Notice Copyright (c) 2020 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction 2. Background 2.1. Multicast Service Models 2.2. ASM Routing Protocols 2.2.1. PIM Sparse Mode (PIM-SM) 2.2.2. Embedded-RP 2.2.3. BIDIR-RP 2.3. SSM Routing Protocols 3. Discussion 3.1. Observations on ASM and SSM Deployments 3.2. Advantages of SSM for Interdomain Multicast 3.2.1. Reduced Network Operations Complexity 3.2.2. No Network-Wide IP Multicast Group-Address Management 3.2.3. Intrinsic Source-Control Security 4. Recommendations 4.1. Deprecating Use of ASM for Interdomain Multicast 4.2. Including Network Support for IGMPv3/MLDv2 4.3. Building Application Support for SSM 4.4. Developing Application Guidance: SSM, ASM, Service Discovery 4.5. Preferring SSM Applications Intradomain 4.6. Documenting an ASM/SSM Protocol Mapping Mechanism 4.7. Not Filtering ASM Addressing between Domains 4.8. Not Precluding Intradomain ASM 4.9. Evolving PIM Deployments for SSM 5. Future Interdomain ASM Work 6. Security Considerations 7. IANA Considerations 8. References 8.1. Normative References 8.2. Informative References Acknowledgments Authors' Addresses 1. Introduction IP Multicast has been deployed in various forms, within private networks, the wider Internet, and federated networks such as national or regional research networks. While a number of service models have been published, and in many cases revised over time, there has been no strong recommendation made by the IETF on the appropriateness of those models to certain scenarios, even though vendors and federations have often made such recommendations. This document addresses this gap by making a BCP-level recommendation to deprecate the use of Any-Source Multicast (ASM) for interdomain multicast, leaving Source-Specific Multicast (SSM) as the recommended interdomain mode of multicast. Therefore, this document recommends that all hosts and routers that support interdomain multicast applications fully support SSM. This document does not make any statement on the use of ASM within a single domain or organization and, therefore, does not preclude its use. Indeed, there are application contexts for which ASM is currently still widely considered well suited within a single domain. The main issue in most cases with moving to SSM is applicationShow full document text