Abstract: In a telecommunications network provisioned with a path based distributed restoration algorithm, upon the detection of a failure in a link, each of the custodial nodes of the failed link sends a special message to the respective end nodes. These end nodes communicate with each other over a communications network independent of the telecommunications network and, in turn, inform the custodial nodes of the identity of the other custodial nodes. By providing each custodial node with the knowledge that its adjacent node is its opposing custodial node, any functional link that cross-connects the custodial nodes is deemed to be of poor quality and, therefore, should not be used as a part of an alternate path for rerouting the disrupted traffic, unless no other alternate path could be found.

Abstract: An optical switching system (and methods) for switching one of a plurality of optical signals. The system has an optical cross-connect apparatus, e.g., MEMS based. The system has a control device coupled to the optical cross-connect apparatus. A multiplexing device is coupled to the optical cross-connect apparatus. A trunk-monitoring device is disposed before the multiplexing device. The trunk-monitoring device being coupled to at least a primary fiber and a back up fiber. The system has a fiber switch coupled between the multiplexing device and the trunk-monitoring device. The fiber switch is adapted to switch an optical signal from the primary fiber to the back up fiber.

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: To ensure the integrity of a telecommunications network provisioned with a distributed restoration algorithm (DRA), a communications network is provided for routing signaling messages such as DRA restoration and maintenance messages among the various nodes of the network. Thus, while data is sent among the nodes via the working links interconnecting the various nodes, signal messages are communicated among the various nodes by way of the independent communications network, which may be a wide area network. By reallocating the signal messages to a separate network, an efficient telecommunications network is effected.

Abstract: In a distributed restoration environment, a node, upon detecting an alarm indicating a failure, after a predetermined period of time, converts the received alarm signal into a modified alarm signal and transmits the thus converted signal to the node adjacent thereto that should have received the same alarm signal to thereby effectively force the failure to be bidirectional if the original failure were a unidirectional failure. The converted signal is sent only after a predetermined period of time has passed to ensure that the failure detected indeed is an actual failure.

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: In a restoration network including a distributed restoration algorithm (DRA) enabled network of a telecommunications network, path verification messages are embedded onto traffic bearing signals entering the network and removed from the signals leaving the network. By adding path verification messages to the signals that traverse within the DRA enabled network, the integrity of any communications path that interconnects the various nodes within the restoration network are confirmed. Further, by removing the path verification messages from the signals leaving the restoration network, equipment outside the restoration network are spared of any possibility that their operations may be affected by the path verification messages.

Abstract: A system and method for restoration of a disrupted telecommunications path between a source node and a destination node via at least one tandem node. The operation of the present invention proceeds in five phases: notification, broadcast, path trace-out, confirmation and cleanup. In the notification phase, the path's source and destination nodes are notified of the disruption. In the broadcast phase, the network is flooded with PACK messages to locate restoration paths; selective rebroadcasting of the PACK messages limits the volume of restoration message traffic. In the path trace-out phase, bandwidth is conservatively reserved along the restoration paths indicated by the PACK messages. In the confirmation phase, restoration paths are built up step-wise along the traced-out paths, thereby restoring the disrupted path between the source and destination nodes.

Abstract: In a telecommunications network having a plurality of intelligent nodes interconnected by multiple communication channels, alternate paths and spare channels are set up for restoring traffic disrupted by failure to one or more of the communications channels. The alternate paths may be set up irrespective of the number of custodial node pairs, also referred to as leader/follower or sender/chooser pairs, that could simultaneously be involved in the restoration operation. The interconnected nodes have bi-directional working and/or spare channels. There is stored at each node in the network participating in the recovery operation a spare channel manifest for each of the leader/follower combinations. The first end node, or leader node, of every identified failed channel initiates a request message for each disrupted working channel to set up an alternate path.

Abstract: All nodes on a malfunctioned communications circuit of a communications network are enabled to identify the location of the fault causing the circuit malfunction. Upon detecting an incoming signal impairment on the circuit, each node on the circuit first assumes that the failure is on the segment of the circuit immediately upstream thereof, and accordingly sends an identifier of that fault location to its downstream nodes. Each node periodically repeats sending its identifier to its downstream nodes. A node that has sent its identifier at least a predetermined number of times without receiving a similar identifier from another node upstream thereof or without having detected a normal signal during all that time is determined to have sent out an identifier that correctly identifies the fault location on the communications circuit.

Abstract: A system having calls substantially selected and dialed to customers at such a paced rate that the system will keep a group of agents at full occupancy with calls on which the system has detected voice answer. As the size of the agent group changes, this predictive pacing is adjusted so that answered calls do not have to be delayed while waiting for an available agent or agents do not have to wait for calls to become available.