Abstract: The present invention provides a system, apparatus and method for accurately identifying optical or digital impairments on a span using FEC errors identified at an intermediary node. This information may be provided to an end node within a network to switch to a redundant path around the impaired optical path or span therein. In one embodiment of the invention, signal degradation is identified by analyzing FEC data within a FEC decoded signal at an intermediary node. An identification of signal degradation provides an indication of a potential failing span within an optical link, which may be provided in-band or out-of-band to a terminal node so that a signal may be switched around a failing path, or span therein, prior to an actual failure event.
Type:
Grant
Filed:
June 30, 2006
Date of Patent:
May 11, 2010
Assignee:
Infinera Corporation
Inventors:
Edward E. Sprague, Marco E. Sosa, Daniel P. Murphy, Christopher C. Liou, Ting-Kuang Chiang, Drew D. Perkins