Node apparatus, route control method, route computation system, and route computation apparatus

A route control method wherein when a topology change occurs on a network used for packet transfer between node apparatuses, the method is used for establishing a new normal route, and said method comprises:

• a receiving step that receives a route control message which includes information required for determining a route on the network;
• a route computing step that determines the route on the network based on the received route control message;
• a sending step that sends a node apparatus a route control message which includes information required for said node apparatus to determine a route on the network;
• a delay computing step wherein when receiving the route control message, the delay computing step computes an operation start time for the determination of the route on the network and the sending of the route control message, based on a distance between a topology change part and a node apparatus of oneself;
• and
• an execution control step that controls the execution of the route determination and the route control message sending, based on the computed operation start time.

A route computation system which operates in an autonomous system, and includes a node apparatus and a damaged part estimating apparatus which are connected via an internal network within the autonomous system, wherein:

• when a topology change occurs on a network used for packet transfer between node apparatuses, the route computation system performs dynamic route control for establishing a new normal route;
• the damaged part estimating apparatus comprises:
• a damaged part estimating device that estimates a topology change part;
• and
• a damaged part communicating devise that communicates the topology change part estimated by the damaged part estimating device to the node apparatus;
• and
• the node apparatus comprises:
• a message receiving device that receives, from another node apparatus, a route control message which includes information required for determining a route on the network;
• a damaged part receiving device that receives the topology change part from the damaged part estimating apparatus;
• a route computing device that determines the route based on the received route control message;
• a message sending device that sends another node apparatus a route control message which includes information required for said another node apparatus to determine a route on the network;
• a delay computing device wherein when receiving the route control message by the message receiving device, the delay computing device computes an operation start time for route control operation executed by the route computing device and the message sending device, based on a distance between the node apparatus of oneself and the topology change part received by the damaged part receiving device;
• and
• an execution control device that controls the execution of the route control operation by the route computing device and the message sending device, based on the operation start time computed by the delay computing device.

A route computation system which operates in an autonomous system, and includes a node apparatus and a distance estimating apparatus which are connected via an internal network within the autonomous system, wherein:

• when a topology change occurs on a network used for packet transfer between node apparatuses, the route computation system performs dynamic route control for establishing a new normal route;
• the distance estimating apparatus comprises:
• a distance estimating device that estimates a distance between the node apparatus and a topology change part;
• and
• a distance communicating devise that communicates the distance estimated by the distance estimating device to the node apparatus;
• and
• the node apparatus comprises:
• a message receiving device that receives, from another node apparatus, a route control message which includes information required for determining a route on the network;
• a distance receiving device that receives, from the distance estimating apparatus, the distance up to the topology change part;
• a route computing device that determines the route on the network based on the received route control message;
• a message sending device that sends another node apparatus a route control message which includes information required for said another node apparatus to determine a route on the network;
• a delay computing device wherein when receiving the route control message by the message receiving device, the delay computing device computes an operation start time for route control operation executed by the route computing device and the message sending device, based on the distance up to the topology change part, which was received by the distance receiving device;
• and
• an execution control device that controls the execution of the route control operation by the route computing device and the message sending device, based on the operation start time computed by the delay computing device.

A route computation apparatus connected to at least one node apparatus among node apparatuses wherein when a topology change occurs on a network used for packet transfer, the route computation apparatus performs dynamic route control for establishing a new normal route, and the route computation apparatus comprises:

• a message receiving device that receives, from said at least one node apparatus, a route control message which includes information required for determining a route on the network;
• a route computing device that determines the route on the network based on the received route control message;
• a message sending device that sends another node apparatus via said at least one node apparatus, a route control message which includes information required for said another node apparatus to determine a route on the network;
• a delay computing device wherein when receiving the route control message by the message receiving device, the delay computing device computes an operation start time for route control operation executed by the route computing device and the message sending device, based on a distance between a topology change part and said at least one node apparatus;
• and
• an execution control device that controls the execution of the route control operation by the route computing device and the message sending device, based on the operation start time computed by the delay computing device.