Patent ID: 7302180

Claim:
A wavelength division multiplexing (WDM) network comprising: two fiber-optic rings, each ring comprising a plurality of terminal nodes and a plurality of hub nodes; each terminal node comprising a main receiver, a redundant receiver, a main transmitter, and a redundant transmitter for each optical carrier associated with the terminal node; and each hub node comprising at least one apparatus adapted for receiving and transmitting information at one optical carrier of a plurality of optical carriers associated with the fiber-optic rings coupled by the hub node, wherein each of said at least one apparatus comprises: a first receiver of the information carried, at said one optical carrier, by the first fiber; a second receiver of the information carried, at said one optical carrier, by the second fiber; a transmitter for transmitting the information, at said one optical carrier, on the second optical fiber; a splitter of an optical power of a signal carried by said one optical carrier, wherein the splitter couples a first portion of the power to the first receiver and couples a second portion of the power to a section of the first fiber; and a first selector selectively switching said one optical carrier from the first fiber to the second fiber.