Gateway system that relays data via a PBX to a computer connected to a pots and a computer connected to an extension telephone and a lanand a method for controlling same

摘要

Disclosed is a gateway system and method for controlling same which allows a video conference to be held with a participant (node) being on a plain old telephone system by using a conventional private telephone system and a LAN. The gateway system relays data, via a private branch exchange, to an information processing unit that is on an external plain old telephone system, and an information processing unit that is connected to an extension telephone and a LAN. The system includes a modem for receiving a call from, or transmitting a call to, the plain old telephone system, and for modulating and demodulating a signal. A multiplexer/demultiplexer is used to multiplex voice information and computer data to prepare a packet, or demultiplex a packet to acquire voice data and computer data separately. A LAN adaptor is used for transmitting and receiving computer data via the LAN. A dialer is provided for making a call to an extension telephone and a digital signal processor is used for coding and decoding voice data. An AD/DA converter is provided for performing analog-to-digital or digital-to-analog conversion on the voice data.