Source-Specific Multicast (ssm)

Last Modified: 2005-02-15

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Description of Working Group:

The purpose of the SSM working group is to define source-specific
multicast in order to provide unambiguous semantics to the designers
of the protocols and host interfaces used in conjunction with
source-specific multicast.

SSM is intended to be a short-lived and highly-focused working group.

The working group has two specific tasks:

1) A concise standards-track RFC that clearly defines the
source-specific multicast model and its relation to RFC 1112
multicast. This document will specify of the host interfaces to be
used for source-specific multicast, the rules that hosts, routers, and
protocols must follow when allocating and using source-specific
addresses. This document will serve as a reference to RFC authors
designing protocols and host interfaces that implement SSM.

2) An informational RFC providing an overview of source-specific
multicast. This document will serve as a starting point for parties
interested in source-specific multicast.

Other SSM-related documents may be taken on as work items by other
multicast working groups that have more specific expertise, including
pim, mboned, and magma. For instance, a document describing the use of
IGMPv3 for SSM has been adopted by MAGMA. The SSM working group chairs
will cooperate with chairs of the related working groups and the Area
Directors to determine the appropriate location of SSM-related
documents that arise during the working group's lifetime.

Goals and Milestones:

Done    First meeting
Done    Submit source-specific multicast model as internet-draft
Done    Submit I-D for source-specific multicast
Done    Reach consensus on source-specific multicast model and alloctate address space to source-specific multicast
Done    Submit I-D on source-specific multicast deployment to IESG for consideration as an Informational RFC
Done    Submit I-D on source-specific multicast to the IESG for consideration as a standards-track RFC
Done    Revise and resubmit I-D on source-specific multicast to the IESG for consideration as a standards-track RFC

No Current Internet-Drafts

Request For Comments:

An Overview of Source-Specific Multicast(SSM) (RFC 3569) (29387 bytes)
Source-Specific Multicast for IP (RFC 4607) (42990 bytes)