Abstract: In a network in which a plurality of communication terminals and at least one server are connected through at least one router, when a network controller, configured to control the network and having a control function of routing of the at least one router in the network and routing information of the at least one router the network, receives an event which changes a destination address of the at least one server, the network controller primarily controls routing information which does not affect a communication being connected and after the processing of changing the destination address has been completed, controls routing information which affects a communication during connecting.

Abstract: An example of a data transport system includes transport nodes of a transport network, communication devices which communicate via the transport network, and a transport network logical path management server for setting logical paths between the transport nodes within the transport network, and a logical path control server. In a case where a first communication device is newly connected with a first transport node, the first communication device transmits control data to a logical path control server via the first transport node. The logical path control server obtains information about a connection relation between the newly connected first communication device and the first transport node from the control data, and establishes a logical path between the first communication device and a second communication device based on the obtained information about the connection relation and on information about logical paths between transport nodes in a logical path database.

Abstract: Communication node including a transmission equipment which communicates user data with transmission equipment of an adjacent node, and a controller which communicates a message with a controller of the adjacent node and which manages the transmission equipment of its own node, wherein: a controller of the node detects existence or nonexistence of fault of a controller of the adjacent node on the basis of situation of receiving a message sent from the controller of the adjacent node; when the controller of the node detects the fault of the controller of the adjacent node, the controller of the node issues a state reference notice to a transmission equipment of its own node and checks existence or nonexistence of fault alert detection; in a case where the fault alert detection of the transmission equipment of the node does not exist, the controller of the node maintains a path state of the node.

Abstract: A monitoring apparatus monitors a transport network connected with a plurality of communication service providing apparatuses configured to provide a plurality of communication services. The transport network includes a plurality of transport apparatuses mutually connected with one another via a plurality of lines. The transport apparatus multiplexes data transmitted by the plurality of communication service providing apparatuses and transfers the multiplexed data via the plurality of lines within the transport network so that the plurality of communication services are accommodated in the plurality of lines. The monitoring apparatus determines whether there is a line at which a failure occurs among the plurality of lines. When determined that there is a line at which a failure occurs among the plurality of lines, the monitoring apparatus calculates a recovery priority indicating a degree of influence of the failure on the plurality of communication services.

Abstract: An arithmetic operation portion including a swap arithmetic operation portion which performs an arithmetic operation of swap information concerned with a path route of a packet, and a label processing portion which sets adjustment of a first label based on a result of the arithmetic operation executed by the swap arithmetic operation portion is provided in a control apparatus to thereby attain compatibility between dispersion of packet transfer load and reduction of an error rate in each link.

Abstract: In an MPLS or GMPLS network, links for hops of a communication path and adaptation to be implemented on the border of management domains or layers are automatically appropriately selected based on a service type or a requirement for maintenance without the necessity of complicating a control sequence. First, a unit that appends an identifier of a service to be provided and an attribute of the service to a communication path establishment control message, and requests path establishment is installed in a source node. Secondly, a unit that determines a requirement for maintenance of the communication path and adaptation on the basis of the service identifier and/or service attribute is installed in each node. Thirdly, maintenance attributes of network resources are compared with the requirement for maintenance in order to determine links and nodes through which the communication path passes.

Abstract: An example of a data transport system includes transport nodes of a transport network, communication devices which communicate via the transport network, and a transport network logical path management server for setting logical paths between the transport nodes within the transport network, and a logical path control server. In a case where a first communication device is newly connected with a first transport node, the first communication device transmits control data to a logical path control server via the first transport node. The logical path control server obtains information about a connection relation between the newly connected first communication device and the first transport node from the control data, and establishes a logical path between the first communication device and a second communication device based on the obtained information about the connection relation and on information about logical paths between transport nodes in a logical path database.

Abstract: Power consumption on GMPLS controlled networks can be reduced by cutting power consumption on spare paths that are not normally used. To achieve power consumption reduction, in the path setting process, a path is calculated while taking the power saving capability of each interface into account, and the applicable interface is set to the power-saving state when setting the spare path. When the spare path was set to the operating state, then the power-saving state on the applicable interface was canceled so that interface could operate normally.

Abstract: Communication node including a transmission equipment which communicates user data with transmission equipment of an adjacent node, and a controller which communicates a message with a controller of the adjacent node and which manages the transmission equipment of its own node, wherein: a controller of the node detects existence or nonexistence of fault of a controller of the adjacent node on the basis of situation of receiving a message sent from the controller of the adjacent node; when the controller of the node detects the fault of the controller of the adjacent node, the controller of the node issues a state reference notice to a transmission equipment of its own node and checks existence or nonexistence of fault alert detection; in a case where the fault alert detection of the transmission equipment of the node does not exist, the controller of the node maintains a path state of the node.

Abstract: A position in which an optical signal characteristic is compensated in an optical network can be chosen. An optical network equipment measures an optical signal characteristic for each wavelength, and notifies an optical network equipment on a communication path of an optical signal characteristic index and control necessity determination threshold. In an upstream portion of the communication path, the optical network equipment (a start point or the like of the communication path) that can compensate the optical signal characteristic for each wavelength determines the necessity to eliminate a deviation between wavelengths and the position to eliminate it, using the optical signal characteristic index and the control necessity determination threshold.

Abstract: In an MPLS or GMPLS network, links for hops of a communication path and adaptation to be implemented on the border of management domains or layers are automatically appropriately selected based on a service type or a requirement for maintenance. First, a unit that appends an identifier of a service to be provided and an attribute of the service to a communication path establishment control message, and requests path establishment is installed in a source node. Secondly, a unit that determines a requirement for maintenance of the communication path and adaptation on the basis of the service identifier and/or service attribute is installed in each node. Thirdly, maintenance attributes of network resources are compared with the requirement for maintenance in order to determine links and nodes through which the communication path passes. The determined links, nodes, and adaptation are designated as action parameters for a switching unit and/or interface unit.

Abstract: In a network wherein a data plane for communicating user data, and a control plane for managing data forwarders are configured of different media, the path teardown of the data plane which is forwarding the data is prevented when a fault has occurred in only the control plane. When the GMPLS controller of the control plane has detected refresh timeout with respect to an adjacent node (101 in FIG. 1), it checks whether or not a transmission equipment corresponding to a faulty controller has a fault (102), and it maintains a path state (103) in a case where the fault is limited to the control plane. Thus, the exchange of refresh messages with the adjacent node is continued without cleaning up the resources of the transmission equipment (104 through 107).

Abstract: In an MPLS/GMPLS network, a link used by a communication path for each hop and adaptations used at the boundary between management domains or layers are appropriately and automatically selected according to a service type and a required maintenance condition, without making a control sequence complicated. First, a unit for requesting path establishment by including an identifier of a service to be provided and a service attribute in a communication path establishment control message is provided for a source node. Second, a unit for determining a required maintenance condition for a communication path and adaptations according to the service identifier and/or the service attribute is provided for each node. Third, links and nodes through which the communication path passes are determined by comparing each of achievable maintenance conditions for network resources with the required maintenance condition.

Abstract: Power consumption on GMPLS controlled networks can be reduced by cutting power consumption on spare paths that are not normally used. To achieve power consumption reduction, in the path setting process, a path is calculated while taking the power saving capability of each interface into account, and the applicable interface is set to the power-saving state when setting the spare path. When the spare path was set to the operating state, then the power-saving state on the applicable interface was canceled so that interface could operate normally.

Abstract: Power consumption on GMPLS controlled networks can be reduced by cutting power consumption on spare paths that are not normally used. To achieve power consumption reduction, in the path setting process, a path is calculated while taking the power saving capability of each interface into account, and the applicable interface is set to the power-saving state when setting the spare path. When the spare path was set to the operating state, then the power-saving state on the applicable interface was canceled so that interface could operate normally.

Abstract: A failure detection protocol is applied so that failure detection requests for the same aggregated link can be processed even when the failure detection requests differ among routing protocols. The failure detection protocol is executed for each of the physical links that form an aggregated link, and a notification is sent to a higher-level application (for example, a routing protocol), which is a requesting source of a communication line failure monitoring request, with a discrimination between a case in which the communication of the aggregated link in its entirety fails and a case in which some physical links of the aggregated link fail.

Abstract: Information that is not dependent on how a GMPLS switch or an MPLS router is set up (information independent of the type of GMPLS switch or MPLS router) is used to obtain attribute values of communication paths and manage communication path configurations in a communication network.

Abstract: A position in which an optical signal characteristic is compensated in an optical network can be chosen. An optical network equipment measures an optical signal characteristic for each wavelength, and notifies an optical network equipment on a communication path of an optical signal characteristic index and control necessity determination threshold. In an upstream portion of the communication path, the optical network equipment (a start point or the like of the communication path) that can compensate the optical signal characteristic for each wavelength determines the necessity to eliminate a deviation between wavelengths and the position to eliminate it, using the optical signal characteristic index and the control necessity determination threshold.

Abstract: In generation of an MPLS path which extends over plural routing areas or generation of a GMPLS path of a single routing area, a path originating node cannot conduct route computation of the whole path. Therefore, where plural paths are generated, there is a problem that reliability and communication quality cannot be secured. In a label switch path generation processing intended for MPLS and GMPLS networks, a path originating node is provided with a unit for setting restricted link information in a label allocation request message and sending it, and a node having received the label allocation request message is provided with a unit for selecting another route, which does not pass through the restricted link according to the restricted link information, and generating a path.

Abstract: A position in which an optical signal characteristic is compensated in an optical network can be chosen. An optical network equipment measures an optical signal characteristic for each wavelength, and notifies an optical network equipment on a communication path of an optical signal characteristic index and control necessity determination threshold. In an upstream portion of the communication path, the optical network equipment (a start point or the like of the communication path) that can compensate the optical signal characteristic for each wavelength determines the necessity to eliminate a deviation between wavelengths and the position to eliminate it, using the optical signal characteristic index and the control necessity determination threshold.