Patent ID: 7280754

Claim:
A two-fiber optical ring network having a plurality of nodes linked by a first fiber optic link and a second fiber optic link, each of the nodes comprising: a first splitting section for splitting optical signals received from the first fiber optic link into protection channels and working channels; a first add/drop section for performing adding and/or dropping —a channel on the working channels received from the first splitting section; a first switching section for combining —the protection channels received from the first splitting section with the working channels that have been output from the add/drop section when there is no link failure between adjacent nodes and for outputting the protection channels received from the first splitting section to the second fiber optic link when there is a link failure between adjacent nodes; and, a controlling section for identifying whether or not the optical link failure occurs in the first and second fiber optic links and for generating a control signal to activate a restoration process according to the identified outcome, wherein when there is optical link failure only the protection channel is switched to the second link.