Alternatively, if the gateway were to route an outgoing telephony call from a calling device, such as a telephone, computer modem or facsimile machine, connected to the PBX over the private data network (to effectuate a ???Voice over IP??? or VoIP call) instead of the PSTN, TDM switch 250, based on control information provided by microcontroller 240, connects an incoming time slot for that call, n