Example of MeGaco messages for Multiplex terminations

Hi,

I have read that a multiplexing termination hides all of the 
terminations it contains from the rest of the context, so the streamIDs 
of the streams flowing between the contained terminations and the 
multiplexing termination are local rather than global in scope.

If e have the following situation:

                         Context interior ---->
                     _________                 _________
        Data stream  | H.226 |                 | H.223 |   Audio stream
Ckt 1 ..............| "MUX" |                 |  MUX  | .................
        . . .        | term  |   Data stream   | term  |
        Data stream  |       | ................|       |   Video stream
Ckt n ..............|       |                 |       | .................
                     |       |                 |       |
                     ---------                 ---------

How we know that the stream between the H.226 and H.223 multiplexing 
terminations is a data stream, while the streams passing from the H.223 
termination to the rest of the context are audio and video?. I think we 
need an explicit description of the exterior-side and context-side 
streams supported by each multiplex somewhere within our Megaco/H.248 
documentation but, how may it be indicated in a MeGaCo meesage?

Also, if we want to use separate RTP terminations for audio and video, I 
need to be able to tell that mux stream 1 shall be mapped to RTP 
termination T3, and stream 2 into RTP termination T4. How may it be 
indicated?


In summary, may someone propose the full MeGaCo messages to create this 
scenario with multiplex terminations?