William L Larson

US Patent:

59498617, Sep 7, 1999

Filed:

Apr 13, 1998

Appl. No.:

9/059635

Inventors:

Christina K. Chan - Northridge CA
Hongsoon H. Kwon - Downey CA
Simon S. Lam - Agoura Hills CA
William A. Larson - Calabasas CA

Assignee:

Northern Telecom Limited - Montreal

International Classification:

H04M 1100

US Classification:

37910017

Abstract:

A system and method for extending the time period at which a facsimile response signal can be received before a time-out occurs without altering the underlying transmission protocol. The disclosed system and method determines a response time before which a response signal must be received by a transmitting facsimile station in order to avoid a time-out event. Before the response time arrives, the disclosed system and method generates and transmits a delay signal to the transmitting facsimile station which does not substantively interfere with ongoing communications. Instead, the delay signal causes the transmitting facsimile station to tickle an internal time-out counter which results in an extension of the response signal delay tolerance. Delay signal frames can be transmitted repeatedly to accommodate any desired time-out period.

US Patent:

57906416, Aug 4, 1998

Filed:

Jun 19, 1996

Appl. No.:

8/666800

Inventors:

Christina K. Chan - Northridge CA
Hongsoon H. Kwon - Downey CA
Simon S. Lam - Agoura Hills CA
William A. Larson - Calabasas CA

Assignee:

Northern Telecom Limited - Montreal

International Classification:

H04M 1100

US Classification:

37910017

Abstract:

A system and method for extending the time period at which a response signal can be received before a time-out occurs without altering the length of the time-out period defined in any transmission protocol, ensuring that the two faxes communicate using one of a predefined, e. g. , standard, set of transmission protocols, and/or ensuring that the two faxes communicate using one of a predefined set of signal modulation techniques. The present invention receives signals transmitted from a local fax and transmits these signals to a remote fax. Similarly, the present invention receives signals transmitted from the remote fax and transmits these signals to the local fax. The present invention examines the contents of the signals and can modify the signal transmitted to the local fax in order to ensure that the two faxes communicate using a transmission protocol that is supported by the present invention and to ensure that the two faxes communicate using a signal modulation technique that is supported by the present invention.