Apparatus and method for optimizing the reconfiguration of an optical network

1. A method for optimizing the configuration of an optical network which is adapted to transport optical traffic along a path from a source node to a destination node, wherein the path can be routed via any one or more of a plurality of intermediate nodes in the optical network, the method comprising the steps of:

receiving an operating parameter of an optical device monitored in one of a plurality of nodes;

comparing the received operating parameter with a threshold value;

determining an operating status of an operating node along the path from the source node to the destination node based on the comparison of the received operating parameter with the threshold value; and

using the determined operating status of a node as a routing criteria for computing a path for routing traffic through the optical network.

2. A method as claimed in claim 1 , wherein the step of receiving an operating parameter comprises the step of receiving an operating parameter relating to the performance of a laser device in a node.

3. A method as claimed in claim 2 , wherein the received operating parameter relating to the performance of a laser device comprises any one or more of:

a bias current of the laser device;

a temperature of the laser device;

the power consumption of the laser device

the peak current used by the laser device; or

the average current used by the laser device.

4. A method as claimed in claim 1 , wherein the steps of receiving and comparing are performed periodically in order to detect a change in the operating status of a node.

5. A method as claimed in claim 4 , wherein the detection of a change in the operating status of a node is used to trigger a reconfiguration of a path in the optical network.

6. A method as claimed in claim 4 , further comprising the step of triggering a node to be removed from the optical network, in response to detecting a change in the operating status of the node.

7. A method as claimed in claim 4 , further comprising the step of reconfiguring the optical network in response to detecting a change in the operating status of a node.

8. A method as claimed in claim 5 , wherein the steps of triggering a reconfiguration, removing a node or reconfiguring the optical network are performed either automatically or semi-automatically.

9. A method as claimed in claim 1 , wherein the path is an unprotected path, and further comprising the steps of:

informing an operator of the network that the operating status of a node has changed; and

proposing one or more alternative paths for the operator to select.

10. A method as claimed in claim 1 , wherein the path is a protection path of a path protection mechanism.

11. A method as claimed in claim 10 , wherein the path is an optical sub-network connection protection (OSNCP) path, and further comprising the step of changing a working path and/or protecting path involving a node where the operating status has changed.

12. A method as claimed in claim 10 , wherein the path is a wavelength switched optical network (WSON) protected path, and further comprising the steps of:

notifying network elements that the operating status of a node has changed;

proposing one or more alternative paths; and

allowing the network elements to manage a new path for the optical traffic.

13. A path computation engine for an optical network adapted to transport optical traffic along a path from a source node to a destination node, the path computation engine comprising:

a receiving unit for receiving a plurality of operating parameters relating to optical devices in nodes of the optical network; and

a processing unit adapted to:

compare a received operating parameter with a respective threshold value;

determine an operating status of an operating node along the path from the source node to the destination node based on the comparison of the operating parameter with the respective threshold value; and

compute a path for routing traffic through the optical network based on the determined operating status of the nodes.

14. A network management node for an optical network comprising a plurality of nodes adapted to transport optical traffic along a path from a source node to a destination node, the network management node comprising:

a receiving unit for receiving a plurality of operating parameters relating to optical devices in the plurality of nodes; and

a processing unit adapted to:

compare the received operating parameters with respective threshold values;

determine the operating status of the plurality of operating nodes along the path from the source node to the destination node based on the comparison of the operating parameters with the respective threshold values; and

configure the optical network based on the determined operating status of the nodes.