Knowledge based path set up and spare capacity assignment for distributed network restoration

In a telecommunications network having a plurality of nodes having respective node identifiers interconnected by a plurality of working channels and spare channels, a system for establishing at least one alternate route for rerouting traffic disrupted by at least one malfunctioned working channel bracketed by a leader node and a follower node, comprising:

• a manifest being provided in each of the nodes of said network, each manifest having at least one identifier representative of a location in the network bracketed by two adjacent nodes to which a fault may occur and at least one spare channel associated with said at least one identifier to be used to establish an alternate path in response to said fault for rerouting the disrupted traffic;
• means at said leader node for accessing the manifest of said leader node to select a path identifier representative of the path between said leader and follower nodes and sending a restoration message including said path identifier onto any available spare channel associated with said path identifier, said path identifier including respective identifiers for said leader node and said follower node and a malfunctioned working channel identifier for identifying said one malfunctioned working channel;
• and
• decision means at each of said nodes other than said leader node, in receipt of said restoration message, for extracting at least said follower node identifier from said restoration message, said each node decision means either reserving the spare channel from which said restoration message was received for said alternate path if the node identifier of said each node is not the same as the follower node identifier extracted from said restoration message or forwarding an acknowledge message onto said spare channel from which said restoration message was received if said each node identifier is the same as said follower node identifier, said acknowledge message being propagated to said leader node;
• said decision means at said leader node, upon receipt of said acknowledge message from the spare channel to which it had sent its restoration message, deciding that an alternate path has been established for rerouting said disrupted traffic.

In a telecommunications network having a plurality of nodes interconnected by a plurality of working channels and spare channels, a method of restoring respective traffic flows disrupted by at least two malfunctioned working channels each occurred between a different pair of adjacent nodes, comprising the steps of:

• (a) provisioning a manifest in each of the nodes of said network, each manifest having a plurality of identifiers each representative of a location in the network bracketed by two adjacent nodes to which a fault may occur and at least one spare channel associated with said each identifier to be used to establish an alternate path in response to said fault for rerouting the disrupted traffic;
• (b) provisioning in said each node a plurality of assignment records each representing the availability of a spare channel connected to said each node;
• (c) each said pair of adjacent nodes
• designating one of said adjacent nodes a leader node and the other of said adjacent nodes a follower node;
• effecting said leader node to access its manifest to select a node pair identifier representative of said each said pair of adjacent nodes and send a restoration message onto said one spare channel associated with said node pair identifier;
• and
• (d) each of said nodes other than said leader node, in receipt of said restoration message from said leader node of said each said pair of adjacent nodes,
• extracting from said restoration message respective identifiers of said leader node and follower node,
• comparing its own node identifier against the follower node identifier extracted from said restoration message,
• deciding it is not a follower node if its node identifier is not the same as said follower node identifier extracted from said restoration message, and propagating said restoration message to its neighbor nodes via available spare channels connected thereto,
• deciding it is said follower node if its node identifier is the same as said follower node identifier extracted from said restoration message, and forwarding an acknowledge message to said leader node on the same spare channel from which said restoration message was received;
• said leader node for said each said pair of adjacent nodes, upon receipt of said acknowledge message from the spare channel to which it had sent its restoration message, deciding that an alternate path has been set up for rerouting the disrupted traffic for the one of said at least two malfunctioned working channels bracketed by said each said pair of adjacent nodes.

In a telecommunications network having a plurality of nodes interconnected by a plurality of working channels and spare channels, a system for restoring respective traffic flows disrupted by at least two malfunctioned working channels each occurred between different pairs of adjacent nodes each having a leader node and a follower node, comprising:

• a manifest provided in each of the nodes of said network, each manifest having a plurality of identifiers each representative of a location in the network bracketed by two adjacent nodes to which a fault may occur and at least one spare channel associated with each of said identifiers to be used to establish an alternate path in response to said fault for rerouting the disrupted traffic;
• a plurality of assignment records each representing the availability of a spare channel connected to said each node provided in said each node;
• means in each leader node of each pair of said different pairs of adjacent nodes for accessing the manifest of said each leader node to select a node pair identifier representative of said each pair of adjacent nodes and send a restoration message onto said one spare channel associated with said selected node pair identifier;
• means in each of said nodes other than said leader nodes, in receipt of said restoration message from said each leader node, for
• extracting from said restoration message identifiers including respective identifiers of said each leader node and its corresponding follower node,
• comparing its own node identifier against the follower node identifier extracted from said restoration message,
• deciding it is not said follower node of said pair of adjacent nodes if its node identifier is not the same as said follower node identifier, and propagating said restoration message to its neighbor nodes via available spare channels connected thereto,
• deciding it is said follower node if its node identifier is the same as said follower node identifier, and forwarding an acknowledge message to said each leader node on the same spare channel from which said restoration message was received;
• and
• means at said leader node for said each pair of said different pairs of adjacent nodes, upon receipt of said acknowledge message from the spare channel to which it had sent its restoration message, for deciding that an alternate path has been set up for rerouting the disrupted traffic for the one malfunctioned working channel bracketed by said each pair of said different pairs of adjacent nodes.

In a telecommunications network having a plurality of nodes interconnected by a plurality of working channels and spare channels, a method of simultaneously restoring traffic disrupted by at least two malfunctioned working channels bracketed by at least one and another pair of custodial nodes, comprising the steps of:

• (a) provisioning a manifest in each of said plurality of nodes of said network, each manifest having at least one identifier representative of two adjacent nodes and at least one spare channel associated with said at least one identifier to be used to establish an alternate path;
• (b) designating said one pair of custodial nodes bracketing a first malfunctioned working channel a one leader node and a one follower node;
• (c) designating said another pair of custodial nodes bracketing a second malfunctioned working channel an other leader node and an other follower node;
• (d) effecting said one and other leader nodes to access their respective manifests to select one and another identifiers representative of said one and another pairs of custodial nodes, respectively, each of said one and another identifiers including respective identifications (IDs) for said corresponding leader and follower nodes;
• (e) effecting said one and other leader nodes to send one and another restoration messages onto any available selected spare channels respectively associated with said one and another identifiers;
• (f) designating as helper nodes said plurality of nodes which are not said leader and follower nodes;
• (g) effecting each of said helper nodes, in receipt of either of said one and another restoration messages, to extract said one or another identifier from said either restoration message and to reserve the spare channel from which said either restoration message was received to set up the alternate path related to said either restoration message;
• (h) effecting said one and other follower nodes, upon receipt of said one and another restoration messages, respectively, to send respective one and another acknowledge messages onto the spare channel from which said one or another restoration message was received;
• (i) propagating said one and another acknowledge messages via said helper nodes, if any, to said one and other leader nodes, respectively;
• (j) effecting said one and other leader nodes, upon receipt of said one and another acknowledge messages, respectively, to determine that corresponding alternate paths have been established for said one and another pairs of custodial nodes;
• and
• (k) rerouting the traffic respectively disrupted by said first and second malfunctioned working channels onto said alternate paths correspondingly established for said one and another pairs of custodial nodes.

In a telecommunications network having a plurality of nodes interconnected by a plurality of working channels and spare channels, a system for simultaneously restoring traffic disrupted by at least a first malfunctioned working channel bracketed by at least one pair of custodial nodes each having a one leader node and a one follower node and a second malfunctioned working channel bracketed by at least another pair of custodial nodes having an other leader node and an other follower node, said plurality of nodes that are not leader or follower nodes being helper nodes, said system comprising:

• a manifest provided in each of said plurality of nodes of said network, each manifest having multiple identifiers each representative of two adjacent nodes and at least one spare channel associated with each of said identifiers to be used to establish an alternate path;
• means in each of said one and other leader nodes for accessing their respective manifests to select one and another identifiers representative of said one and another pairs of custodial nodes, respectively, each of said one and another identifiers including respective identifications (IDs) for said corresponding leader and follower nodes;
• means in said one and other leader nodes each for sending one and another restoration messages, respectively, onto any available selected spare channels respectively associated with said one and another identifiers;
• means in each of said helper nodes, in receipt of either of said one and another restoration messages, for extracting said one or another identifier from said either restoration message and to reserve the spare channel from which said either restoration message was received to set up the alternate path related to said either restoration message;
• and
• means in said one and other follower nodes, upon receipt of said one and another restoration messages, respectively, for sending respective one and another acknowledge messages onto the spare channel from which said one or another restoration message was received, said one and another acknowledge messages being propagated via said helper nodes, if any, to said one and other leader nodes, respectively;
• said means in said one and other leader nodes, upon receipt of said one and another acknowledge messages, respectively, determining that corresponding alternate paths have been established for said one and another pairs of custodial nodes so that the traffic respectively disrupted by said first and second malfunctioned working channels are rerouted onto said alternate paths correspondingly established for said one and another pairs of custodial nodes.