Roni,

The proposal is limited to the case where multicast is used when a MC does not exert control over the conference.  That is, when two devices are in a point-to-point call.  One example of where this is useful is when a PBX wants to put a call on hold and “music on hold” is broadcast by a server to all devices that are on hold.  In this case, for example, a PBX (or phone) might send a TCS=0 to the held party and then send an OLC proposing a multicast address.

Any use of multicast that involves an MC (or transmission of the communication mode table) is outside the scope of this proposed addition and is already addressed by H.323.

Paul

From: Even, Roni [mailto:roni.even@polycom.co.il]
Sent: Tuesday, January 29, 2008 12:25 PM
To: Paul E. Jones; itu-sg16@lists.packetizer.com
Subject: RE: [itu-sg16] AVD 3299

Paul,

This works in point to point and I am not sure why you need multicast in this case. Also you are not doing multicast H.245. So there is an MC

Now let's take the case of an MC that has three participants in the multicast group.

The first one sends an OLC with payload type 100. The second one sends an OLC with payload type 101 and the third with payload type of 102. Now the MC needs to send an OLC to the first participant, which payload type should it use 101,102,100?

Roni

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From: Paul E. Jones [mailto:paulej@packetizer.com]
Sent: Tuesday, January 29, 2008 6:47 PM
To: Even, Roni; itu-sg16@lists.packetizer.com
Subject: RE: [itu-sg16] AVD 3299

Roni,

I guess I am still missing your point.  This is a means of sending media, just like unicast.  The payload type numbers are selected by the sender, just as they are for unicast.  If the recipient accepts the proposed OLC, then it would listen on the multicast address for incoming media accordingly.

Paul

From: Even, Roni [mailto:roni.even@polycom.co.il]
Sent: Tuesday, January 29, 2008 11:24 AM
To: Paul E. Jones; itu-sg16@lists.packetizer.com
Subject: RE: [itu-sg16] AVD 3299

Paul,

Is the multicast uni-directional, is it just a point to point. If it is to be used to enable the EP to send media to a multicast group this should be aligned with the media the other side except to receive. How does it get set

Roni

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From: Paul E. Jones [mailto:paulej@packetizer.com]
Sent: Tuesday, January 29, 2008 6:20 PM
To: Even, Roni; itu-sg16@lists.packetizer.com
Subject: RE: [itu-sg16] AVD 3299

Roni,

I don’t understand your concern.  Can you clarify the problem?

Paul

From: itu-sg16-bounces@lists.packetizer.com [mailto:itu-sg16-bounces@lists.packetizer.com] On Behalf Of Even, Roni
Sent: Tuesday, January 29, 2008 11:06 AM
To: itu-sg16@lists.packetizer.com
Subject: [itu-sg16] AVD 3299

Hi,

I looked at the document and I think I understand the OLC procedure. I need it does not address how you decide on a dynamic payload type number when needed.

The OLC gives the dynamic payload type number to send

Roni