Patent ID: 7804615

Claim:
A method for processing an IP facsimile, wherein a calling fax machine in a PSTN and a called fax machine in the PSTN are connected by Internet, and a called gateway and a calling gateway are provided between transceivers in the PSTN and the Internet to modulate and demodulate data between a PTSN data package and an IP data package, the method comprising: a. setting a highest bit rate available for the called gateway; b. setting up a call connection between the calling fax machine and the called fax machine via the PSTN connected by the Internet; c. the calling fax machine and the called fax machine handshaking to determine a highest available bit rate, wherein the called fax machine sends a digital identification signal frame, in which an information word includes a highest facsimile bit rate provided by the called fax machine, the called gateway taking out the highest facsimile bit rate from the information word after receiving the frame and comparing the highest facsimile bit rate with a highest bit rate available for the called gateway, if the highest facsimile bit rate is higher than the highest bit rate available for the called gateway then the highest available bit rate is amended to the highest bit rate available for the called gateway, and then the frame is transmitted to the calling fax machine; d. the calling fax machine taking out the highest available bit rate from the information word of the frame after receiving the digital identification signal frame, then comparing the highest available bit rate with the highest bit rate provided by the calling fax machine, then creating a digital command signal frame that includes a bit rate that is the lower of the highest available bit rate from the information word or the highest bit rate provided by the calling fax machine and sending the digital command signal frame to the called fax machine, the bit rate included in the digital command signal frame being the highest bit rate at which a message is transmitted between the calling fax machine and the called fax machine.