The media service provider interfaces are documented in the MSDN libraries. The DevSpice sample on the SDK CD gives an example of how to use the MSP for media streaming and device specific functionality.

The MSP is available to every TAPI address that can be viewed in your TAPI 3 application. Media streaming capabilities are only available to addresses that are specifically named as WAVE users. WAVE users are users with a name that begins with "TAPI:" (Such as "TAPI:201" ).

You can create as many WAV users as you wish, but each WAVE user will require a wave driver licence instance to enable media streaming to that user.