A method and apparatus for optimizing optical transport using a software defined network (SDN) controller are disclosed herein. The SDN controller may define a margin optimization function based on at least one optical system performance metric. The function may include at least one related initiation criterion. Further, the SDN controller may collect at least one measurement for the performance metric. The measurement may include an assessment of deployed carriers not carrying client data. The SDN controller may determine whether the initiation criterion is met based on at least one collected measurement. The SDN controller may select a system margin optimization mechanism and define a system margin optimization threshold criterion on a condition that the initiation criterion is met. The SDN controller may determine whether the optimization threshold criterion is met. The SDN controller may implement one or more optimization events on a condition that the optimization threshold criterion is met.

In some embodiments, an apparatus comprises a memory and a processor operatively coupled to the memory. The processor is configured to receive, from a forward error correction (FEC) decoder of an optical transponder, a first plurality of pre-FEC bit error rate (BER) values at a plurality of times to identify a degradation over a first transmission path. The processor is configured to determine, based on the first plurality of pre-FEC BER values, a signal pattern. The processor is configured to adjust, based on the signal pattern, a set of parameters including a first threshold and a second threshold. The processor is configured to send, in response to a second pre-FEC BER value exceeding the second threshold and being below the first threshold, a signal to trigger traffic rerouting to a second transmission path to reduce traffic loss due to the degradation over the first transmission path.

A software-defined network multi-layer controller (SDN-MLC) may communicate with multiple layers of a telecommunication network. The SDN-MLC may have an optimization algorithm that helps in capacity planning of the telecommunications based on the management of multiple layers of the telecommunication network.

A method implemented by a domain controller in a network comprises transmitting, by a transmitter of the domain controller to a super controller, an update message comprising path information for one or more parallel paths having a common wavelength from a source to a destination, wherein the one or more parallel paths are free of optical impairments when the update message is transmitted to the super controller, receiving, by a receiver of the domain controller from the super controller, an initiate message comprising an identifier of a path selected from the one or more parallel paths, and provisioning, by a processor of the domain controller, the path based on a verification that the path selected by the super controller is free of optical impairments.

Systems and methods for allocating optical circuits on optical mesh networks are disclosed herein. For example, the disclosed methods include identifying a new circuit to be added to a mesh optical network and identifying a set of potential paths for the new circuit. For each optical link in each identified potential path, costs are determined for a plurality of frequency slots of allocating the new circuit to a potential path including the optical link. The cost of allocating a given frequency slot on a given optical link is determined in part based on the lengths of optical circuits that can traverse the given optical link using that frequency slot. Total cost values are calculated for allocating available frequency slots over each of the identified potential paths, and one of the identified potential paths and one or more of the available frequency slots are allocated for the new circuit.

A computer-implemented method is implemented in one of a Network Management System (NMS), an Element Management System (EMS), a Software Defined Networking (SDN) controller, and a server executing an SDN application, to increase capacity of one or more links in an optical network. The computer-implemented method includes determining Net System Margin comprising a metric of overall excess margin in the optical network until a Forward Error Correction (FEC) limit is reached; performing an optimization of a plurality of parameters of the optical network to determine which settings are appropriate in the optical network to provide the increased capacity and to consume at least part of the Net System Margin; and causing a plurality of modems in the optical network to change settings based on the optimization to provide the increased capacity.

A network controller controls optical nodes configured to communicate with each other at multiple line rates using different tuples of [bits/symbol, symbol rate] for each line rate. The network controller determines multiple paths between two optical nodes, selects a desired line rate at which to communicate between the two optical nodes, and accesses a path database that indicates an available optical bandwidth and an available optical signal-to-noise ratio (SNR) along each path. The network controller determines feasible paths among the paths. To do this, the network controller, for each path, searches the different tuples of the desired line rate for a tuple for which a desired optical bandwidth and a desired optical SNR are accommodated by the available optical bandwidth and the available optical SNR of the path, respectively. The network controller programs optical nodes of one of the feasible paths with a tuple found in the searching.

A method implemented by a domain controller in a network comprises transmitting, by a transmitter of the domain controller to a super controller, an update message comprising path information for one or more parallel paths having a common wavelength from a source to a destination, wherein the one or more parallel paths are free of optical impairments when the update message is transmitted to the super controller, receiving, by a receiver of the domain controller from the super controller, an initiate message comprising an identifier of a path selected from the one or more parallel paths, and provisioning, by a processor of the domain controller, the path based on a verification that the path selected by the super controller is free of optical impairments.

An optical access network includes an optical hub having at least one processor. The network further includes a plurality of optical distribution centers connected to the optical hub by a plurality of optical fiber segments, respectively, and a plurality of geographic fiber node serving areas. Each fiber node serving area of the plurality of fiber node serving areas includes at least one optical distribution center of the plurality of optical distribution centers. The network further includes a plurality of end points. Each end point of the plurality of end points is in operable communication with at least one optical distribution center. The network further includes a point-to-point network provisioning system configured to (i) evaluate each potential communication path over the plurality of optical fiber segments between a first end point and a second end point, and (ii) select an optimum fiber path based on predetermined path selection criteria.

To address the problem of an increase in the complexity of the structure of a ROADM device using a WSS device when WSS is multiplexed or made redundant, an optical transmission device includes an optical add-drop multiplexer which produces an output by multiplexing/demultiplexing arbitrary wavelengths into or from first signal light and second signal light that are input, and a multiplexer/demultiplexer to which the input of the first signal light and the second signal light is switched, characterized in that the multiplexer/demultiplexer is transmissive to a predetermined wavelength band of the first signal light, and produces an output by multiplexing/demultiplexing the first signal light that has been transmitted and the second signal light.