An Overview of Source-Specific Multicast (SSM) (RFC3569)
Original Publication Date: 2003-Jul-01
Included in the Prior Art Database: 2003-Jul-08
Internet Society Requests For Comment (RFCs)
S. Bhattacharyya: AUTHOR [+2]
The purpose of this document is to provide an overview of Source-Specific Multicast (SSM) and issues related to its deployment. It discusses how the SSM service model addresses the challenges faced in inter-domain multicast deployment, changes needed to routing protocols and applications to deploy SSM and interoperability issues with current multicast service models.
Network Working Group S. Bhattacharyya, Ed.
Request for Comments: 3569 Sprint
Category: Informational July 2003
An Overview of Source-Specific Multicast (SSM)
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 (C) The Internet Society (2003). All Rights Reserved.
The purpose of this document is to provide an overview of
Source-Specific Multicast (SSM) and issues related to its deployment.
It discusses how the SSM service model addresses the challenges faced
in inter-domain multicast deployment, changes needed to routing
protocols and applications to deploy SSM and interoperability issues
with current multicast service models.
This document provides an overview of the Source-Specific Multicast
(SSM) service and its deployment using the PIM-SM and IGMP/MLD
protocols. The network layer service provided by SSM is a "channel",
identified by an SSM destination IP address (G) and a source IP
address S. An IPv4 address range has been reserved by IANA for use
by the SSM service. An SSM destination address range already exists
for IPv6. A source S transmits IP datagrams to an SSM destination
address G. A receiver can receive these datagrams by subscribing to
the channel (Source, Group) or (S,G). Channel subscription is
supported by version 3 of the IGMP protocol for IPv4 and version2 of
the MLD protocol for IPv6. The interdomain tree for forwarding IP
multicast datagrams is rooted at the source S, and is constructed
using the PIM Sparse Mode  protocol.
This document is not intended to be a standard for Source-Specific
Multicast (SSM). Instead, its goal is to serve as an introduction to
SSM and its benefits for anyone interested in deploying SSM services.
It provides an overview of SSM and how it solves a number of problems
faced in the deployment of inter-domain multicast. It outlines
changes to protocols and applications both at end-hosts and routers
Bhattacharyya Informational [Page 1]
RFC 3569 An Overview of SSM July 2003
for supporting SSM, with pointers to more detailed documents where
appropriate. Issues of interoperability with the multicast service
model defined by RFC 1112 are also discussed.
This memo is a product of the Source-Specific Multicast (SSM) Working
Group of the Internet Engineering Task Force.
The keywords "MUST"", "MUST NOT", "REQUIRED", "...