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Re: [AVT] RTP: Note regarding SSM



At 09:51 PM 1/7/2003 -0800, Mark Baugher wrote:
Steve,

At 03:20 PM 1/7/2003 -0800, Stephen Casner wrote:
One of the IESG comments (this one from Harald Alvestrand) was a
request to add the following "non-normative note" at the end of
Section 6 where RTCP is introduced (i.e., just before 6.1).  Does
anyone object?

        Non-normative note:  In the multicast routing approach
        called Source-Specific Multicast (SSM), only one or a few
        senders send multicast data, and receivers may not send
        multicast.
It has been awhile since I read the SSM I-Ds, but this does not sound right to me. I scanned the documents in http://www.ietf.org/html.charters/ssm-charter.html and cannot find anything about multicast receivers being prevented from sending multicast packets (a multicast sender is also a receiver, right?).
excuse me, a sender that joins/subscribes to (S,G) is also a receiver.

Mark

SSM defines an (S,G) "channel" that allows receivers to select certain senders to group G. I don't know where it is specified that receivers may not send multicast.

Mark

The recommendations here accommodate SSM only
        through Section 6.2's option of turning off receivers' RTCP
        entirely.  Future work will specify adaptation of RTCP for
        SSM so that feedback from receivers can be maintained.

                                                        -- Steve

_______________________________________________
Audio/Video Transport Working Group
avt@ietf.org
https://www1.ietf.org/mailman/listinfo/avt
_______________________________________________
Audio/Video Transport Working Group
avt@ietf.org
https://www1.ietf.org/mailman/listinfo/avt
_______________________________________________
Audio/Video Transport Working Group
avt@ietf.org
https://www1.ietf.org/mailman/listinfo/avt