Abstract: A failure detected network node, which detects a network failure that is assumed to occur at a location in a current communication path through network nodes, is determined. A failure notification time for each network node is then calculated. After that, a first network node is selected from the network nodes, based on the failure notification time. The first network node is positioned in the current communication path on upper stream from the location of the network failure. Finally, an alternative communication path, which includes the first network node and a second network node out of the network nodes, is determined. The second network node is positioned in the current communication path on down stream from the location of the network failure.

Abstract: A network design device includes: a division section for dividing a network having a plurality of channels and branch nodes into a plurality of linear partial networks using a predetermined terminating node or each branch node as the terminating nodes by allocating a device terminating one or more channels to be used to the terminating node and each branch node; an allocation unit for allocating a linear relay device and/or a reproduction relay device to a node constituting each partial networks to which a device has been allocated by the allocation unit; and a deletion unit for deleting a device terminating the channel allocated to the branch node for each path formed by the path formation unit according to the signal performance.

Abstract: A communications network system, which is comprised of a management network, a control network, and a user transmission network, includes signaling-based communication apparatuses, each consisting of a control node and a communication node, and non-signaling-based communication apparatuses without having associated control nodes. In this system, a path can be established in a user data transmission network by controlling a signaling process on the control network. The configuration of the communication node of the non-signaling-based communication apparatus is changed by a network management system provided in the management network, while the configuration of the communication nodes of the signaling-based communication apparatus are changed by the associated control nodes by successively transmitting a signaling message to the next control node on the control network.

Abstract: A protecting route design method is disclosed for a communication network including a plurality of nodes having preset information on a protecting route to switch over in parallel from a working route thereto when link or node failure occurs, according to a failure notification message including failure location information being transmitted from a failure detection node to each node. The protecting route design method includes the steps of searching a protecting route which can minimize a transfer time of the failure notification message from the failure detection node; and then, updating the searched protecting route to a protecting route having a spare communication capacity sharable for a different failure and having a route switchover time to be completed within a given time limit.

Abstract: A network design device includes: a division section for dividing a network having a plurality of channels and branch nodes into a plurality of linear partial networks using a predetermined terminating node or each branch node as the terminating nodes by allocating a device terminating one or more channels to be used to the terminating node and each branch node; an allocation unit for allocating a linear relay device and/or a reproduction relay device to a node constituting each partial networks to which a device has been allocated by the allocation unit; and a deletion unit for deleting a device terminating the channel allocated to the branch node for each path formed by the path formation unit according to the signal performance.

Abstract: A failure detected network node, which detects a network failure that is assumed to occur at a location in a current communication path through network nodes, is determined. A failure notification time for each network node is then calculated. After that, a first network node is selected from the network nodes, based on the failure notification time. The first network node is positioned in the current communication path on upper stream from the location of the network failure. Finally, an alternative communication path, which includes the first network node and a second network node out of the network nodes, is determined. The second network node is positioned in the current communication path on down stream from the location of the network failure.

Abstract: A network management system in plural networks connected to each other, which offers the improved efficiency and convenience of network maintenance and management. When collecting and managing subnetwork information out of device information as device subnetworks in plural networks connected to each other, a subnetwork manager divides the device subnetwork of a connecting device belonging to the plural networks into plural divided subnetworks corresponding to the plural networks for management. A user interface controls the display of the device subnetworks and plural divided subnetworks.

Abstract: A communications network system, which is comprised of a management network, a control network, and a user transmission network, includes signaling-based communication apparatuses, each consisting of a control node and a communication node, and non-signaling-based communication apparatuses without having associated control nodes. In this system, a path can be established in a user data transmission network by controlling a signaling process on the control network. The configuration of the communication node of the non-signaling-based communication apparatus is changed by a network management system provided in the management network, while the configuration of the communication nodes of the signaling-based communication apparatus are changed by the associated control nodes by successively transmitting a signaling message to the next control node on the control network.

Abstract: A spare path design method for a communication network in which spare path information is set in each node of the communication network constituted of a plurality of nodes based on a database, a fault notification message including fault location information is transferred from a fault detection node to each node when a link fault or a node fault occurs. The nodes receiving the fault notification message switch the path in parallel. The spare path design method includes comparing the maximum fault notification time among the nodes located on a second spare path with the maximum fault notification time among the nodes located on a first spare path when a resource sharing condition is satisfied; and as a result of the comparison, if the time in the second path is shorter, replacing the spare path by the second spare path to update spare path information stored in the database.

Abstract: A protecting route design method is disclosed for a communication network including a plurality of nodes having preset information on a protecting route to switch over in parallel from a working route thereto when link or node failure occurs, according to a failure notification message including failure location information being transmitted from a failure detection node to each node. The protecting route design method includes the steps of searching a protecting route which can minimize a transfer time of the failure notification message from the failure detection node; and then, updating the searched protecting route to a protecting route having a spare communication capacity sharable for a different failure and having a route switchover time to be completed within a given time limit.