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.

A multi-layer network planning system can determine a set of regenerator sites (“RSs”) that have been found to cover all paths among a set of nodes of an optical layer of a multi-layer network and can determine a set of candidate RSs in the optical layer for use by the links between a set of nodes of an upper layer, wherein each RS can be selected as a candidate RS for the links. The system can determine a binary path matrix for the links between the set of nodes of the upper layer. The system can determine a min-cost matrix that includes a plurality of min-cost paths. The system can determine a best RS from the set of candidate RSs and can move the best RS from the set of candidate RSs into the set of RSs for the links. The system can then update the binary path matrix.

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 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 multi-layer network planning system can determine a set of regenerator sites (“RSs”) that have been found to cover all paths among a set of nodes of an optical layer of a multi-layer network and can determine a set of candidate RSs in the optical layer for use by the links between a set of nodes of an upper layer, wherein each RS can be selected as a candidate RS for the links. The system can determine a binary path matrix for the links between the set of nodes of the upper layer. The system can determine a min-cost matrix that includes a plurality of min-cost paths. The system can determine a best RS from the set of candidate RSs and can move the best RS from the set of candidate RSs into the set of RSs for the links. The system can then update the binary path matrix.

Techniques for providing closed-loop control and predictive analytics in packet-optical networks are described. For example, an integrated, centralized controller provides tightly-integrated, closed-loop control over switching and routing services and the underling optical transport system of a communication network. In one implementation, the controller includes an analytics engine that applies predictable analytics to real-time status information received from a monitoring subsystem distributed throughout the underlying optical transport system. Responsive to the status information, the analytics engine applies rules to adaptively and proactively identify current or predicted topology-changing events and, responsive to those events, maps reroutes packet flows through a routing/switching network and control and, based on any updated bandwidth requirements due to topology changes, dynamically adjusts allocation and utilization of the optical spectrum and wavelengths within the underlying optical transport system.

Various embodiments for configurable memory storage systems are disclosed. The configurable memory storages selectively choose an operational voltage signal from among multiple voltage signals to dynamically control various operational parameters. For example, the configurable memory storages selectively choose a maximum voltage signal from among the multiple voltage signals to maximize read/write speed. As another example, the configurable memory storages selectively choose a minimum voltage signal from among the multiple voltage signals to minimize power consumption.

The invention discloses a communication method includes: receiving, by the ONU by using the first port or the second port, a wavelength switching request message delivered by the OLT, where the wavelength switching request message carries second wavelength channel information and port information that is of the second port; switching, by the ONU, an operating wavelength channel of an optical module connected to the second port from a first wavelength channel to a second wavelength channel corresponding to the second wavelength channel information; and sending, by the ONU, a wavelength switching complete message to the OLT by using the first port. According to the communication method provided in embodiments of the present invention, quick wavelength switching is performed based on the second port, so that a service is not interrupted in a wavelength switching process, and user experience is better.

In an optical communication abnormality-recovery system and method, when an abnormality occurs in transmission and reception of one wavelength of an optical line terminal of a PON system, an optical network unit that is performing communication at a certain wavelength switches the wavelength for performing the communication to another backup wavelength that is instructed in advance. The optical line terminal also performs switching so that the communication is performed using the same backup wavelength as in the optical network unit.

A method (10) of controlling optical signal power levelling in an optical communication network node configured to apply an optical attenuation, α, to a pass-through optical signal. The method comprises: a. performing the following steps i. to iii. until an attenuation variation value, Δα, is greater than a preselected attenuation variation threshold value (18), Δα.sub.TH: i. measuring (12) an optical signal power of an optical signal; ii. calculating (14) a difference, ΔP, between the measured optical signal power and a target optical signal power; iii. calculating (16) a value for the attenuation variation, Δα, to be applied to the optical attenuation taking account of ΔP; b. obtaining (20) a current value of the optical attenuation, α.sub.n, and obtaining (22) a new optical attenuation value, α.sub.n+1, in dependence on the current value of the optical attenuation, a current value of the attenuation variation, Δα.sub.n, and at least an earlier value of the attenuation variation, Δ.sub.αn−1; and c. generating (24) a control signal arranged to configure the node to apply the new optical attenuation value, α.sub.n+1.