3.3.5.8 Sending a Media Type List Request
The structure and fields of the Media Type List Request message are specified in section 2.2.3.7.
The server sends this message to obtain a list of stream formats supported by the specified video stream. The server MUST send this message only after a successful Activate Device Request (section 3.3.5.5) message and before any Deactivate Device Request (section 3.3.5.21) message.