Real time fax-over-packet for broadband access gateways

Abstract

The invention teaches elimination of the need for allocating a telephony port or equivalent processor resource for realtime facsimile transmission through a broadband access gateway by replacing a fax modem or analog fax machine with a computer system having a network connection to the gateway. A software application on the computer uses a serial port redirector that provides a virtual communication port for facsimile software applications that would otherwise use a fax modem on a computer. The port redirector captures fax data sent to a serial communication port on the computer and sends it to the virtual fax module on the gateway. The gateway has a virtual fax software application associated which emulates a Class 1 or Class 2 fax modem interface from the client-side PC. The gateway uses a codec to convert fax data into ITU T.38 standards for 'Procedures for real-time Group 3 facsimile communication over IP networks'. Packetized T.38 facsimile data is then transmitted to a far-end gateway that may be located at a central office (CO) of a telephone company or other network. The elimination of a telephony port in the gateway allows for the simplified approach to sending and receiving fax over IP networks by reducing the processing complexity in the system and frees up telephony resources in the gateway device.