Device and method for correcting a path trouble in a communication network

A backup path bandwidth keeping method for keeping a bandwidth of a backup path to which an active path is switched when the active path becomes unavailable in nodes of a communication network,

• wherein L (L is a natural number or 0) channels that are kept as a backup path bandwidth and that are connected to the same destination are defined as backup channels in each node, the backup path bandwidth keeping method includes:
• a step of a keeping a backup path bandwidth, when keeping the bandwidth of the backup path, by sending identification information indicating that a path for which the bandwidth is to be kept is a backup path, and sending risk classification number information of at least one of a link or a node of the link and the node through which an active path passes, to a destination-side node existing in a destination side of the backup path via each node on a route, the route being determined for the backup path before sending the identification information to the destination-side node;
• and
• a step of sending, before the active path becomes unavailable and to a source side node existing in a start point side of the backup path via each node on the route, a signaling message for keeping the bandwidth of the backup path, the signaling message including, for each link of the backup path, channel identification information of a backup channel that is kept or that is to be kept when performing failure switching or channel group identification information of a backup channel group, the channel identification information and the channel group identification information each specifying a communication resource to be used by the backup path on each link through which the backup path passes,
• wherein the channel identification information identifies a particular channel as the backup channel and the channel group identification information identifies a particular backup channel group as the backup channel group.

A backup path bandwidth keeping method for keeping a bandwidth of a backup path to which an active path is switched when the active path becomes unavailable in nodes of a communication network,

• wherein L (L is a natural number or 0) channels that are kept as a backup path bandwidth and that are connected to the same destination are defined as backup channels in each node, the backup path bandwidth keeping method includes:
• a step of keeping a backup path bandwidth, when keeping the bandwidth of the backup path, by sending identification information indicating that a path for which the bandwidth is to be kept is a back up path, sending risk classification number information of at least one of a link or a node of the link and the node through which an active path passes, and sending identification information of a backup channel that is a candidate to be kept, or identification information of a plurality of backup channels, to a destination-side node existing in a destination side of the backup path via each node on a route, the route being determined for the backup path before sending the identification information to the destination-side node;
• and
• a step of sending, before the active path becomes unavailable and to a source side node existing in a start point side of the backup path via each node on the route, a signaling message for keeping the bandwidth of the backup path, the signaling message including, for each link of the backup path, channel identification information of a backup channel that is kept or that is to be kept when performing failure switching or channel group identification information of a backup channel group, the channel identification information and the channel group identification information each specifying a communication resource to be used by the backup path on each link through which the backup path passes,
• wherein the channel identification information identifies a particular channel as the backup channel and the channel group identification information identifies a particular backup channel group as the backup channel group.

A path switching apparatus comprising a path setting management function part for keeping a bandwidth of a backup path to which an active path is switched when the active path that is set in a communication network becomes unavailable, wherein the path setting management function part includes:

• a backup path setting process part including a function for managing, as backup channels, L (L is a natural number or 0) channels that are kept as a backup path bandwidth and that are connected to the same destination;
• and
• a signaling process part for, when keeping the bandwidth of the backup path,
• receiving identification information indicating that a path for which the bandwidth is to be kept is a backup path that are reported from a first adjacent node on a source side, searching for an output port corresponding to the backup path, and outputting, to a second adjacent node on a destination side, identification information indicating that a path for which bandwidth is to be kept for an output side of the backup path is a backup path;
• and
• receiving, before the active path becomes unavailable and from the second adjacent node, a signaling message for keeping the bandwidth of the backup path, the signaling message including, for each link of the backup path, identification number information of a backup channel or channel group identification information of a backup channel group, the identification number information and the channel group identification information each specifying a communication resource to be used by the backup path on each link through which the backup path passes;
• and
• outputting the identification number information of the backup channel or the channel group identification information of the backup channel group to the first adjacent node,
• wherein the channel identification information identifies a particular channel as the backup channel and the channel group identification information identifies a particular backup channel group as the backup channel group, and
• wherein the first adjacent node, the path switching apparatus, and the second adjacent node are on a route, the route being determined for the backup path before outputting the identification information to the destination-side second adjacent node.

A path switching apparatus comprising a path setting management function part for keeping a bandwidth of a backup path to which an active path is switched when the active path that is set in a communication network becomes unavailable, wherein the path setting management function part includes:

• a backup path setting process part including a function for managing, as backup channels, L (L is a natural number or 0) channels that are kept as a backup path bandwidth and that are connected to the same destination;
• and
• a signaling process part for, when keeping the bandwidth of the backup path,
• receiving identification information indicating that a path for which the bandwidth is to be kept is a backup path, and receiving risk classification number information of at least one of a link or a node of the link and the node through which an active path passes that are reported from a first adjacent node on a source side, searching for an output port corresponding to the backup path, and outputting, to a second adjacent node on a destination side, identification information indicating that a path for which bandwidth is to be kept for an output side of the backup path is a backup path, and risk classification number information of at least one of a link or a node of the link and the node through which an active path passes;
• and
• receiving, before the active path becomes unavailable and from the second adjacent node, a signaling message for keeping the bandwidth of the backup path, the signaling message including, for each link of the backup path, identification number information of a backup channel or channel group identification information of a backup channel group, the identification number information and the channel group identification information each specifying a communication resource to be used by the backup path on each link through which the backup path passes, and outputting the identification number information of the backup channel or the channel group identification information of the backup channel group to the first adjacent node,
• wherein the channel identification information identifies a particular channel as the backup channel and the channel group identification information identifies a particular backup channel group as the backup channel group, and
• wherein the first adjacent node, the path switching apparatus, and the second adjacent node are on a route, the route being determined for the backup path before outputting the identification information to the destination-side second adjacent node.

A path switching apparatus comprising a path setting management function part for keeping a bandwidth of a backup path to which an active path is switched when the active path that is set in a communication network becomes unavailable,

• wherein L (L is a natural number or 0) channels that are kept as a backup path bandwidth and that are connected to the same destination are defined as backup channels in each node, the path setting management function part includes:
• a backup path bandwidth keeping process part for, when keeping the bandwidth of the backup path, by sending identification information indicating that a path for which the bandwidth is to be kept is a backup path, and sending risk classification number information of at least one of a link or a node of the link and the node through which an active path passes, to a destination-side node existing in a destination side of the backup path via each node on a route, the route being determined for the backup path before sending the identification information to the destination-side node;
• and
• a processing part for sending, before the active path becomes unavailable and to a source side node existing in a start point side of the backup path via each node on the route, a signaling message for keeping the bandwidth of the backup path, the signaling message including, for each link of the backup path, channel identification information of a backup channel that is kept or that is to be kept when performing failure switching or channel group identification information of a backup channel group, the channel identification information and the channel group identification information each specifying a communication resource to be used by the backup path on each link through which the backup path passes,
• wherein the channel identification information identifies a particular channel as the backup channel and the channel group identification information identifies a particular backup channel group as the backup channel group.

A path switching apparatus comprising a path setting management function part for keeping a bandwidth of a backup path to which an active path is switched when the active path that is set in a communication network becomes unavailable,

• wherein L (L is a natural number or 0) channels that are kept as a backup path bandwidth and that are connected to the same destination are defined as backup channels in each node, the path setting management function part includes:
• a backup path bandwidth keeping process part for, when keeping the bandwidth of the backup path, by sending identification information indicating that a path for which the bandwidth is to be kept is a backup path, sending risk classification number information of at least one of a link or a node of the link and the node through which an active path passes, and sending identification information of a backup channel that is a candidate to be kept, or identification information of a plurality of backup channels, to a destination-side node existing in a destination side of the backup path via each node on a route, the route being determined for the backup path before sending the identification information to the destination-side node;
• and
• a processing part for sending, before the active path becomes unavailable and to a source side node existing in a start point side of the backup path via each node on the route, a signaling message for keeping the bandwidth of the backup path, the signaling message including, for each link of the backup path, channel identification information of a backup channel that is kept or that is to be kept when performing failure switching or channel group identification information of a backup channel group, the channel identification information and the channel group identification information each specifying a communication resource to be used by the backup path on each link through which the backup path passes,
• wherein the channel identification information identifies a particular channel as the backup channel and the channel group identification information identifies a particular backup channel group as the backup channel group.