Optical path communication network, node, and optical path setup method

A node which is utilized in an optical path communication network which comprises a source node, a destination node, and transit nodes which are deployed upon a route between the source node and the destination node, comprising:

• a unit which transmits an optical path setup request, when the node operates as the source node;
• a unit which reserves a resource which is to be used for setting up an optical path based upon the optical path setup request, when the node operates as the destination node;
• a unit which transmits a resource reservation request, when the node operates as the destination node;
• a relay unit which, along with relaying towards the destination node the optical path setup request which has been received from a previous hop node, relays towards the source node the resource reservation request which has been received from a next hop node, when the node operates as one of the transit nodes;
• a notification unit which notifies towards the destination node available resource information which specifies available resources related to its own node which are to be used for setting up an optical path, when the node operates as the source node or as one of the transit nodes;
• a pre-assignment unit which pre-assigns the available resources which the notification unit of its own node has notified, based upon the optical path setup request, when the node operates as the source node or as one of the transit nodes;
• an actual reservation unit which actually reserves one of the available resources which have been pre-assigned, based upon the resource reservation request, when the node operates as the source node or as one of the transit nodes;
• and
• a unit which releases the ones among the resources which have been pre-assigned other than the one thereof which is actually reserved, when the node operates as the source node or as one of the transit nodes.

A program which, by being installed upon an information processing device, implements upon the information processing device functions which correspond to each node which is employed in an optical path communication network which comprises a source node, a destination node, and transit nodes which are deployed upon a route between the source node and the destination node, the program comprising the functions of:

• as a function when operating as the source node, implements a function of transmitting an optical path setup request;
• as a function when operating as the destination node, implements a function of reserving a resource which is to be used for setting up an optical path based upon the optical path setup request, and a function of transmitting a resource reservation request;
• as a function when operating as one of the transit nodes, implements a relay function of relaying towards the destination node the optical path setup request which has been received from a previous hop node, and relaying towards the source node the resource reservation request which has been received from a next hop node;
• and
• as a function when operating as the source node or as one of the transit nodes, implements a notification function of notifying towards the destination node available resource information which specifies available resources related to its own node which are to be used for setting up an optical path, a pre-assignment function of pre-assigning the available resources which the notification function of its own node has notified, based upon the optical path setup request, an actual reservation function of actually reserving one of the available resources which have been pre-assigned, based upon the resource reservation request, and a function of releasing the ones among the resources which have been pre-assigned other than the one thereof which is actually reserved.

A method of setting up an optical path, applied to an optical path communication network which comprises a source node, a destination node, and transit nodes which are deployed upon a route between the source node and the destination node, comprising the steps of:

• the source node, along with transmitting an optical path setup request, notifies towards the destination node available resource information which specifies available resources related to the source node which are to be used for setting up an optical path, and pre-assigns the available resources which its own node has notified;
• each of the transit nodes, along with relaying towards the destination node the optical path setup request which has been received from a previous hop node, notifies towards the destination node available resource information which specifies available resources related to each of the transit nodes, and pre-assigns the available resources which its own node has notified;
• the destination node, along with reserving a resource which is to be used for setting up an optical path based upon the optical path setup request which has been received from the previous hop node, transmits a resource reservation request towards the source node;
• each of the transit nodes, along with relaying towards the source node the resource reservation request which has been received from a next hop node, actually reserves one of the available resources which have been pre-assigned, based upon the resource reservation request, and releases the ones among the resources which have been pre-assigned other than the one thereof which is actually reserved;
• and
• the source node actually reserves one of the available resources which have been pre-assigned, based upon the resource reservation request which has been received from the next hop node, and releases the ones among the resources which have been pre-assigned other than the one thereof which is actually reserved.