Abstract: A system for use in a bi-directional path switched ring network for detecting a failed optical path and establishing a protection path so as to allow signals from the failed optical path to be re-routed via the protection path is provided. According to one aspect of the system, upon detecting a failure relating to an optical path, the destination node generates a connection request message for transmission to the source node. The connection request message is passed to the source node via one or more intermediate nodes, if any. Each intermediate node examines the connection request message accordingly reserves the requisite wavelength from the protection capacity so as to allow signals from the failed optical path to be re-routed. Upon receiving the connection request message, the source node readies its switching equipment to re-route signals from the failed optical path and generates an acknowledgment message and propagates it back to the destination node via the intermediate nodes.

Abstract: A system for use in a bi-directional path switched ring network for detecting a failed optical path and establishing a protection path so as to allow signals from the failed optical path to be re-routed via the protection path is provided. According to one aspect of the system, upon detecting a failure relating to an optical path, the destination node generates a connection request message for transmission to the source node. The connection request message is passed to the source node via one or more intermediate nodes, if any. Each intermediate node examines the connection request message accordingly reserves the requisite wavelength from the protection capacity so as to allow signals from the failed optical path to be re-routed. Upon receiving the connection request message, the source node readies its switching equipment to re-route signals from the failed optical path and generates an acknowledgment message and propagates it back to the destination node via the intermediate nodes.

Abstract: A network wherein a plurality of links connects a plurality of nodes such as cross-connects in a communication circuit network with paths interconnecting the nodes, and with there being spare capacity between a sufficient number of nodes to accommodate at least some rerouting of traffic immediately upon detection of a break in a traffic span in the network so as to restore circuit continuity within a predetermined maximum time using an improved failure detection, isolation, and recovery

Abstract: A network wherein a plurality of links connects a plurality of nodes such as cross-connects in a communication circuit network with paths interconnecting the nodes, and with there being spare capacity between a sufficient number of nodes to accommodate at least some rerouting of traffic immediately upon detection of a break in a traffic span in the network so as to restore circuit continuity within a predetermined maximum time using an improved failure detection, isolation, and recovery scheme.

Abstract: In a path-based distributed restoration algorithm provisioned telecommunications network, the origin and destination nodes of a failed path are apprised of the portions of the path that remain intact by “reuse” messages that are sent from the custodial nodes that are adjacent to the failure. As each reuse message reaches an intermediate node, the node ID of the intermediate node is appended to a field of the message so that, as the reuse messages are propagated along the intact portions of the failed path, a cumulative list of nodes that are encountered by the messages passing from the custodial nodes to the origin and destination nodes is set forth. Thus, the origin/destination node, when in receipt of a reuse message, can read from the field that has the cumulative list of nodes a description of the intact portions remaining from the original path.

Abstract: In a telecommunications network provisioned with different types of restoration processes, to ensure that the operation of one restoration process does not infringe upon other nodes that are actively executing a different restoration process, a request is sent by one of the restoration processes, under the guise of the operation system that oversees that process, to the operation system that oversees the other restoration process. The controller of the nodes that are performing the other restoration process, in receipt of the request, sends a disable restoration process message to those nodes under its control. Each of those nodes, upon receipt of the disable restoration process message, would disable the restoration process it is provisioned with so long as it is not actively engaging in that restoration process. If it is, it will continue to execute that restoration process until a safe stop point is reached, at which time it ceases that restoration process.

Abstract: In a telecommunications network provisioned with a distributed restoration scheme, to determine the reactions and responses of the network while the network is “live” or operational, an exercise information message is provided to the network for presenting a simulated failure or failures thereto. This exercise information message is broadcast to all of the nodes of the network so that every node is aware of the simulated failure scenario. Modified DRA messages that indicate that they are exercise only messages are used by the nodes for executing the exercise restoration process. Such exercise restoration process will proceed as if an actual failure has occurred with the notable exception that no actual cross-connections will be made. Certain functionalities are provisioned to the nodes to allow the exercise restoration process to be aborted if a real failure is detected or upon the expiration of a timer.

Abstract: A system and method for restoring communication between at least one pair of nodes in a network. Distributed intelligence is provided by messaging between adjacent nodes in the network. The messages in combination with user-configurable timers and rules provide fault isolation, forward flooding, reverse linking and connection.

Abstract: A system and method for restoring communication between at least one pair of nodes in a network. Distributed intelligence is provided by messaging between adjacent nodes in the network. The messages in combination with user-configurable timers and rules provide fault isolation, forward flooding, reverse linking and connection.