Systems and methods for resolving control conflicts in trunk protection links are provided. A method, in one implementation, includes identifying control conflicts among Network Elements (NEs) in an Optical Multiplex Section (OMS). The OMS may have a plurality of trunk protection links arranged in parallel and a plurality of Trunk Protection Switches (TPSs). Also, the trunk protection links and TPSs are configured to create a distributed 1:N trunk protection arrangement. The method also includes resolving the control conflicts by auto-negotiating a primary instance associated with enabling a first set of control actions to be conducted along a primary path in the OMS and auto-negotiating one or more follower instances associated with enabling a second set of control actions to be conducted along one or more secondary paths in the OMS subsequent to the first set of control actions.

Systems and methods for managing a list or restoration paths are provided. A method, according to one implementation, includes obtaining a list of restoration paths used for restoring transmission in a network when a home path between an originating node and a termination node is unavailable. The restoration paths are listed in a specific order based on ongoing transmission costs, where the ongoing transmission cost for each restoration path is based on characteristics associated with transmitting signals along the respective restoration path. The method also includes the step of reordering the restoration paths in the list based on restoration costs and the ongoing transmission costs. The restoration cost for each restoration path is based on a procedure for switching from the home path to the respective restoration path.

Systems and methods are provided for controlling one or more optical amplifiers of a C+L band photonic line system (30) of a telecommunications network in which C-band signals and L-band signals may be transmitted. In one implementation, a method (130) may execute a traffic managing module (23). When executed, the traffic managing module (23) may be configured to enable a processing device (12) to calculate (132) a gain correction profile based on a difference between a saved baseline transmission profile (84) and a measured transmission profile (94) of a surviving band of a photonic line system (30) when another band of the photonic line system (30) is missing or impacted. The traffic managing module (23) may further be configured to enable the processing device (12) to apply (134) the gain correction profile to a respective optical amplifier (46) of the photonic line system (30) to compensate for the difference.

Systems and methods for resolving control conflicts in trunk protection links are provided. A head-end node includes a first line-mux controller and a second line-mux controller, first actuator components for a first fiber span, and second actuator components for a second fiber span, wherein the first line-mux controller and the second line-mux controller are configured to control the first actuator components and the second actuator components, respectively, and a trunk protection switch configured to connect an input to each of the first fiber span and the second fiber span.

A transmission device for which a work path is established in a first degree and a protection path is established in a second degree includes: a switch equipped with a plurality of optical ports; an optical signal generator, optically connected to a first optical port, and configured to generate an optical signal that is transmitted through the work path; and a monitor light generator, optically connected to a second optical port, and configured to generate monitor light by using a wavelength tunable light source. The monitor light generator controls a wavelength of the monitor light to be substantially the same as a wavelength of the optical signal. The switch guides the optical signal that arrives at the first optical port toward the first degree and guides the monitor light that arrives at the second optical port toward the second degree.

An optical add/drop multiplexer branching apparatus is provided in the embodiments of the present invention, where the optical add/drop multiplexer branching unit includes: a trunk input end, a branch input end, a trunk output end, a branch output end, an optical add/drop multiplexer, a first coupler, a first detection circuit, and a control circuit, where the optical add/drop multiplexer includes an optical switch. A detection circuit detects whether a fault occurs in a trunk, and in a case in which a fault occurs in the trunk, a working mode is switched from a first working mode to a second working mode, to implement automatic redundancy on the trunk and ensure normal communication on a branch.

A system and method is disclosed in which circuitry of a first controller of a first node on a first path within a transport network receives a first signal indicating a failure within the first path from a second controller. The first node is an end node of the first path. A first client signal failure clear signal is received from a second node upstream of the first node on the first path. The first client signal failure clear signal indicates that a non-restorable fault has been resolved such that the first path can be considered for carrying data traffic. The non-restorable fault is a failure at the source. Subsequent to receiving the first signal indicating the failure within the first path, a backward defect indication clear signal is transmitted to the second node, the backward defect indication clear signal indicating an absence of a failure in the first path.

Systems and methods include, responsive to a fault affecting an optical service on an active path in an optical network operating at a frequency μ1 via an optical transceiver and having optical line protection via an optical protection switch, switching to an inactive path that now becomes the active path and finding a new route in the optical network for the inactive path that has the fault; responsive to being unable to find a route at the frequency μ1, switching the inactive path to a new route at a different frequency μ2; and implementing spectrum coordination relative to the inactive path to either determine the frequency μ1 is available on the new route or to find another new route for the inactive path where the frequency μ1 is available.

Provided is a multiplex transmission system capable of preventing occurrence of a mistake on connection of a client device to a multiplex transmission device. The multiplex transmission system includes: a detection means configured to detect new client connection that is new connection of a client device to a client port of each of a first multiplex transmission device 100 and a second multiplex transmission device 200; and a switch control unit 340 configured to control a switch unit 330 to connect a client port where new client connection is detected at a first time point in the first multiplex transmission device 100 with a client port where new client connection is detected at a second time point in the second multiplex transmission device, when a time interval between the first time point at which new client connection is detected in the first multiplex transmission device 100 and the second time point at which new client connection is detected in the second multiplex transmission device 200 is within a preset reference time, in a case where new client connection is detected in both the first multiplex transmission device 100 and the second multiplex transmission device 200.

Described herein is an apparatus including a continuous wave idler and an optical coupler that provide an optical signal having a power greater than optical channels carrying data, and positioned at a cross-over point between two spectral bands, with each band encompassing multiple optical channels.