This object specifies the RTP payload type used when adding VoIP trunking connections, where IANA values 0-95 are static payload types, 96-127 are dynamic, 128-255 are reserved for future extension, and 256 is a special default meaning the DSP should assign a payload type automatically to avoid conflicts between gateways. An administrator sets this to match the payload type expected by the far-end gateway, or leaves it at the default 256 to let the DSP negotiate a non-conflicting value automatically. For example, an administrator interoperating with a third-party gateway that expects a specific dynamic payload type would set this object to a value in the 96-127 range rather than relying on the 256 default.