Setting up precalculated alternate path for circuit following failure in network

A method of operating a node for a telecommunications network, the node using Generalized Multiprotocol Label Switching (GMPLS) protocol and having a switch, the method comprising:

• setting up a circuit along a main path through nodes of the network, the circuit having one or more precalculated alternate paths for the circuit, stored locally, for use in an event of failure of the main path;
• responding to an indication of failure of the main path for the circuit by causing a check to be made of whether one or more of the precalculated alternate paths is currently valid, based on whether the network resources needed by the one or more alternate paths are currently available, according to a local dynamically updated routing database;
• and
• setting up the switch and communicating with other nodes using the GMPLS protocol to set up one of the alternate paths for that circuit based on an outcome of the check.

A non-transitory computer-readable medium having computer instructions stored therein, which when executed by a node for a telecommunications network, the node using Generalized Multiprotocol Label Switching (GMPLS) protocol and having a switch, cause the node to perform operations comprising:

• setting up a circuit along a main path through nodes of the network, the circuit having one or more precalculated alternate paths for the circuit, stored locally, for use in an event of failure of the main path;
• responding to an indication of failure of the main path for the circuit by causing a check to be made of whether one or more of the precalculated alternate paths is currently valid, based on whether network resources needed by the one or more alternate paths are currently available, according to a local dynamically updated routing database;
• and
• setting up the switch and communicating with other nodes using the GMPLS protocol to set up one of the alternate paths for that circuit based on an outcome of the check.