Subject: Re: RTSP

From: David Oran <[email-masked]>
Date: Thu, 17 Oct 1996 15:07:58 -0400

THANKS! That really clears up a lot of confusion (at least in my mind -
maybe everybody else is already clued in). By the way, it was real hard to
imagine what I could/couldn't or would/wouldn't use the protocol for from
reading the draft. More of this sort of stuff in the Introduction would
definitely have been helpful.

Now, another naive question. You talk about one-to-one and one-to-many as
being in the scope, but not many-to-many. Ok, now what about many-to-one?
In other words, I want to retrieve a bunch of streams from a variety of
sources (i.e. not all on the same control host or media server) and control
them together. I'm not sure how one would do that with RTSP. Set up some
kind of intermediate proxy which makes it look like the streams all come
from the same place? Set up multiple RTSP connections/associations, one per
media server? I think I know how to do some of that with a per-stream
control channel like RTCP, or with a multicast control protocol that all
the media servers can listen to.

Thanks for being patient. Dave.

At 11:15 AM 10/17/96 -0700, Rob Lanphier wrote:
>At 04:18 PM 10/15/96 -0400, David Oran wrote:
>>Rob, I'm curious what you see as the scope of "controlling all aspects
>>of transmission". Could you give some examples outside the VCR-button
>>domain of what you envision?
>>
>>Just to stimulate discussion, what about an I-Phone conference using RTP
>>and you want to put the phone on "hold". Is that in the scope of RTSP, part
>>of the IK-phone session protocol, or something that belongs in RTCP?
>
>Just to clear up a major bit of confusion here.  I think we are very
>interested in eventually controling all aspects of one-to-many one-way
>transmission (recording, playback, etc.).  However, controlling many-to-many
>transmission is an *entirely* different can of worms, and I think is best
>left to another protocol, such as what Jeff Smith at NTT is working on for
>collaborative control.
>
>Beyond VCR-button-type control, what we envision in the long-term is full
>a/v mixer board control, rather than the telephone/conferencing paradigm.  I
>see that goal as orthoganal to telephone conferencing control.
>
>Rob
>---
>Rob Lanphier               Voice: (206)674-2322         Fax: (206)674-2699
>Program Manager-Protocols                         Email: [email-masked]
>Progressive Networks-Home of RealAudio       Web: http://www.realaudio.com
>
>
>
-----------------
David R. Oran
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