In order to add a CDC function to a ROADM system currently incompatible with CDC, without requiring any service outage, an optical communication system of the present invention includes: an optical demultiplexing unit 1-1 and 1-2 which each demultiplexes a wavelength-multiplexed optical signal inputted thereto and an optical multiplexing unit 2-1 and 2-2 which each multiplexes together some of, specifically at least two or more of, the components of the wavelength-multiplexed optical signal having been demultiplexed by the optical demultiplexing unit 1-1 or 1-2; and an optical path selection unit 3 which selectively outputs either the optical signal multiplexed by the optical multiplexing unit 2-1 or that by the optical multiplexing unit 2-2, in a form of at least two or more output optical signals.

An optical network is configured to optimize network resources. The optical network includes multiple optical nodes, light paths between the multiple optical nodes, and a network monitoring device. The network monitoring device monitors the optical network to identify a failure in the optical network. When the failure is a fiber failure, light paths are re-routed around the fiber failure while maintaining the required bandwidth for the optical network. When the failure is a transponder card failure within one of the multiple nodes, a floating spare card may be provisioned to service a particular light path associated with the transponder card failure. When the failure is a node failure, transponder cards in some of the multiple optical nodes are provisioned to reconfigure some of the plurality of light paths to route traffic around the failed node.

A method of validating connections in an optical add/drop multiplexer (OADM) that includes a plurality of modules configured to route optical signals through the OADM, and at least one multi-fiber cable connecting modules of the OADM. A light source coupled to a first port of a first module is controlled to emit a test light. A determination is made whether or not the test light is received at a first photo-detector connected to a second port. Continuity of a connection between the first port and the second port is validated when the test light is received at the first photo-detector.

Example embodiments of the present invention relate to An optical node comprising of at least two optical degrees; a plurality of directionless add/drop ports; and at least one wavelength equalizing array, wherein the at least one wavelength equalizing array is used to both select wavelengths for each degree, and to perform directionless steering for the add/drop ports.

The invention relates to an optical communication network (1) comprising a plurality of nodes (2) connected to each other by means of optical fibers (3) in a ring structure, wherein optical signals are transported at working wavelengths (.sub.w) in a first direction in said ring structure and wherein optical signals are transported at protection wavelengths (.sub.p) in a second direction that is opposite to the first direction in said ring structure, wherein for each node (2) at least one wavelength assignment table (WAT) is provided, wherein to each working wavelength (.sub.w) a corresponding protection wavelength (.sub.p) is assigned, wherein in case of a detected connection failure in said ring structure each node (2) which loses at least one connection performs for all working wavelengths (.sub.w) affected by said connection failure a lookup in its wavelength assignment table (WAT) to determine the respective protection wavelength (.sub.p) and tunes lasers of transceiver units to the determined protection wavelengths (.sub.p).

A method may include interleaving, by an optical device, a set of bits of a first channel with a set of bits of a second channel. The first channel may include first forward error correction (FEC) data associated with the set of bits of the first channel and the second channel may include second FEC data associated with the set of bits of the second channel. The method may further include transmitting first information via the first channel and second information via the second channel. The first information may include a portion of the set of bits of the first channel, a portion of the set of bits of the second channel, and the first FEC data. The second information may include another portion of the set of bits of the first channel, another portion of the set of bits of the second channel, and the second FEC data.

To provide a wavelength multiplexing device and the like that can effectively identify whether impairment occurs at a location before or after a separation and switching module, a wavelength multiplexing device (100) is connected to one or more optical fiber line systems and to one or more optical transceiver systems and is disposed between the optical fiber lines and optical transceivers so as to input and output optical signals, and is provided with the following: first optical switches (12a-12c) that output an optical signal input from an optical line to an optical transceiver; second optical switches (12d-12f) that output an optical signal input from an optical transceiver to an optical fiber line; and a local optical loopback circuit (13) that feeds back and outputs an optical signal input from an optical transceiver (21-23) to that optical transceiver.

A reconfigurable optical switch apparatus comprising m input ports, m output ports, k add ports, k drop ports and a switch matrix comprising mk wavelength selective optical switches arranged in m rows and k columns. Each switch comprises first, second, third and fourth ports. The columns are grouped in adjacent pairs, in each pair a first column being connected to a respective drop port on a first side of the switch matrix and each wavelength selective switch in said first column having the fourth port arranged on said first side and a second column, adjacent the first column, being connected to a respective drop port on a second side, opposite the first side, of the switch matrix and each wavelength selective switch in said second column having the fourth port arranged on said second side.

A network component comprising at least one processor configured to implement a method comprising collecting wavelength availability information associated with a wavelength switched optical network (WSON), receiving a path computation request to transport a signal through the WSON, calculating at least one route through the WSON for the signal, and assigning at least one wavelength for the signal to use along the route. Also disclosed is a network comprising a first path computation element (PCE) configured to compute at least one route for a signal between a source and a destination, and a second PCE in communication with the first PCE, wherein the second PCE is configured to receive the route from the first PCE and assign at least one wavelength to the route.

It is difficult to increase the number of inputs and outputs of an optical switch supporting CDC functions, therefore, an optical switch according to an exemplary aspect of the present invention includes a unit optical switch inputting n optical signals and outputting n optical signals; an optical splitter inputting a single optical signal, splitting the single optical signal into k optical signals, and outputting the k optical signals; and an optical selector inputting m optical signals and outputting a single optical signal, wherein the optical splitter includes mn pieces, the unit optical switch includes mk pieces, the optical selector includes nk pieces, (k(mn)) outputs of the optical splitter correspond to (n(mk)) inputs of the unit optical switch, (n(mk)) outputs of the unit optical switch correspond to (m(nk)) inputs of the optical selector, and (nm) optical signals inputted into the optical splitter are output through the (mk) unit optical switch from the optical selector as (nk) optical signals.