Maria Centeno Mendez

US Patent:

60756292, Jun 13, 2000

Filed:

Jan 27, 1998

Appl. No.:

9/014174

Inventors:

Daniel Yousef Al-Salameh - Marlboro NJ
Nathan Myron Denkin - Aberdeen NJ
Wei-Chiao William Fang - Middletown NJ
Maria F. Mendez - Elizabeth NJ

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

H04B 1018

US Classification:

359110

Abstract:

A bi-directional protection facility is provided in an optical communication system in which an optical communications node communicates with another optical communications node via first and second bi-directional communications paths respectively serving as a service path and protection path, and in which a filter at each node processes signals respectively received over the service and protection paths and generates an in-band signal and out-of-band signal for each of the paths. A control unit then generates a Loss of Signal indication for the service path if the level of the out-of-band signal is found to be greater than the level of the in-band signal and protection switching is effectuated as a function of the presence of the control signal. In addition, an outgoing signal to the other communications node is interrupted for a sufficient period of time to cause a LOS at that node and thus trigger protection switching thereat to complete the bi-directional switching process.