Patent ID: 6480585
Filing Date: 2002-11-12
Classification: H04L,H04N

Abstract:
A data communications system in a facsimile machine, comprising:a processor coupled to a local interface; a memory coupled to the local interface; and data communications logic stored on the memory and executable by the processor, the data communications logic comprising: logic to initiate a virtual data communications link with a peer facsimile machine through a first public switched telephone network (PSTN) link, a first gateway, a network, a second gateway, and a second PSTN link; logic to negotiate a data rate with the peer facsimile including logic to determine whether the peer facsimile supports a pulse code modulation (PCM) communications mode; logic to transmit a command to the second gateway to employ the PCM communications mode in a downstream direction with the peer facsimile if the peer facsimile supports the PCM communications mode; and logic to transmit an upstream data signal in the first PSTN link using a pulse code modulation if the peer facsimile supports the PCM communications mode.