Abstract: When opposed communication transmitting apparatuses A and C are connected in a physical configuration thorough a communication transmitting apparatus B, if an interface configuration changing command is input to the communication transmitting apparatus B, the interface configuration is changed in the communication transmitting apparatus B and virtual connection is achieved such that the opposed communication transmitting apparatuses A and C pass through the communication transmitting apparatus B to directly connect an interface A1 and an interface C1. In this situation, since the GMPLS operation target apparatuses are only the communication transmitting apparatus A and the communication transmitting apparatus C and the communication transmitting apparatus B is a non-target apparatus of the GMPLS operation, the GMPLS scalability problem is solved and optical signals may be transferred at higher speed.

Abstract: Information for performing path control is added to a signaling message used in a network including a higher-level path which accommodates a lower-level path. When a state change occurs in the higher-level path, a communication device extracts using the information a lower-level path to be controlled for the same control item as the control item indicating the state change in the higher-level path. A path to be controlled is selected from among the lower-level paths accommodated in the higher-level path. By controlling the extracted path, a plurality of paths can be easily controlled when there are accommodation relationships among layers.

Abstract: A communication control apparatus includes a storage unit and a processor. The storage unit stores, in association with a port number, first address information regarding apparatuses connected to a port identified by the port number. The processor receives a first affected address list containing second address information regarding apparatuses which may be affected by a trouble, extracts the first address information stored in the storage unit in association with a port number of a port via which the first affected address list has been received, selects third address information which is included in both the first and second address information, updates the first affected address list by replacing the second address information with the third address information to acquire a second affected address list, and transmits the second affected address list via each port other than the port via which the first affected address list has been received.

Abstract: A route designing method in which there is accepted an input of user information containing information about bandwidth of an access link serving as a link for connecting each of user sites to a relay node, and information showing the relay node connecting to the user site via the access link, topology information of a network for relaying the communications between the user sites is acquired, a communication relay port and a communication non-relay port are obtained based on the user information and the topology information, an upper limit of the communication bandwidth available for the user on the communication relay port is obtained, a route design so that the user sites are connected by a tree-shaped route is performed, and a result of the route design is outputted.

Abstract: A method of migrating a virtual machine from a first computer to a second computer includes: performing an external communication of the virtual machine via a first buffer before starting migration of the virtual machine, performing an external communication of the virtual machine via a second buffer different from the first buffer during the migration, starting the migration upon receiving a request for migrating the virtual machine, storing information destined for the virtual machine in the second buffer upon receiving the information during the migration, and transferring the information stored in the second buffer to the second computer in response to termination of the virtual machine.

Abstract: A transmission device including at least one transmitter/receiver unit that is coupled to another transmission device via a communication line, a power supply unit that supplies power to the at least one transmitter/receiver unit, and a control unit that notifies the another transmission device about first sleep start information specifying time at which an operating mode of the at least one transmitter/receiver unit is to be changed to a sleep mode and that stops the supply of power from the power supply unit to the at least one transmitter/receiver unit at the time specified by the first sleep start information.

Abstract: A node for configuring a ring type network system in such a mode that a plurality of physical links belonging to difference rings exists between nodes opposite to each other, has a storage unit stored with link associated information representing an associated relationship between ports of physical links and a port of a virtual link virtually set up to at least one physical link, ring configuration information representing a paired relationship of the ports of the physical links configuring the different ring, port numbers of both ends of the physical link and port numbers of both ends of the virtual link, and a processing unit executing a process of transmitting, to other nodes, such information that one virtual link is associated with the plurality of physical links belonging to the different ring, and setting up, when receiving a signaling message for setting up a path, the path passing through the same ring on the basis of pass route information in the message and the storage information stored in the sto

Abstract: A route calculation apparatus calculates an intra-domain route in a target domain assigned with the route calculation apparatus. The intra-domain route is a part of a route for a target path in a network divided into plural domains. Each of the plural domains includes at least one node device. The target path passes through transit domains out of the plural domains from a source node device included in a source domain to a destination node device included in a destination domain. The route calculation apparatus includes a calculator and a route calculation requester. The calculator calculates the intra-domain route in the target domain. The route calculation requester requests a first route calculation apparatus assigned to the destination domain to calculate an intra-domain route in the destination domain when the target domain is one of the plural domains except the destination domain and except domains adjacent to the destination domain.

Abstract: Information for performing path control is added to a signaling message used in a network including a higher-level path which accommodates a lower-level path. When a state change occurs in the higher-level path, a communication device extracts using the information a lower-level path to be controlled for the same control item as the control item indicating the state change in the higher-level path. A path to be controlled is selected from among the lower-level paths accommodated in the higher-level path. By controlling the extracted path, a plurality of paths can be easily controlled when there are accommodation relationships among layers.

Abstract: To provide a device and a method enabling a user to judge which route a path used at the present traces without being aware of whether the now-in-use path is a working path or a recovery path. A relay device positioned at a diverging node between the working path and the recovery path, when forwarding a message (e.g., a Path message and a Resv message each containing RRO) used for route trace, judges which type of path the path employed for forwarding the data at the present is coincident with and forwards the data to the relay device disposed on the in-use path, thereby actualizing the trace of the route used for forwarding the data at the present.

Abstract: A relay node used in a WDM optical network is disclosed. The relay node includes: a high-speed side port configured to send and receive a high-speed signal; a low-speed side port configured to send and receive a low-speed signal; a unit configured to generates a checking message for requesting another node to report constraint information of a low-speed side port of the another node, wherein the constraint information relates to adding an optical signal from the low-speed side port to a high-speed side port of the another node or dropping an optical signal from the high-speed side port to the low-speed side port of the another node; a unit configured to generate a response message including the constraint information of the own node in response to receiving the checking message sent from the another node; and a storing unit configured to store at least the constraint information of the another node.

Abstract: A transmission device, which carries out a route control of a frame based on a label included in the frame in a ring network, includes: a generating unit that generates a message for collecting information on first/second labels allocatable to working/standby routes; a transmitting unit that transmits the message in the ring network; a receiving unit that receives the message after being circulated in the ring network; and a selecting unit that selects one of the first/second labels for the working/standby route based on the information included in the message.

Abstract: The present invention relates to a communication path calculation method and module. More particularly, the present invention provides a communication path calculation method and module that are implemented or incorporated in a transmission apparatus including a ROADM or the like which performs WDM communication, advertises information on a wavelength which can be added or dropped, as information on a link, and uses the information to autonomously calculate a communication path. Optical transmission equipment that is accommodated in a WDM network over which a wavelength-division multiplexed signal is transferred includes a reconfigurable OADM module. For calculation of a communication path, the OADM module creates a link table listing clients of the own equipment and connected WDMs, and advertises the link table to the other pieces of equipment accommodated by the network as pieces of information on restrictions to be imposed on routing from the own equipment.

Abstract: A path routing computation method enables reduction of the memory capacity for path routing computation. The method is characterized in that a wavelength convertible subnetwork in which paths are connected in a mesh form; a first and second wavelength inconvertible subnetworks have a starting point node and an end point node, respectively, and include a plurality of nodes and connected via the wavelength convertible subnetwork, and out of the nodes constituting the first and second wavelength inconvertible subnetworks, a node has a port connected to the wavelength convertible subnetwork is defined as a border node, and the method includes the steps of: obtaining, for the first wavelength inconvertible subnetwork, a path from the starting point node to a border node in the first subnetwork; and obtaining, for the second wavelength inconvertible subnetwork, a path from the end point node to a border node in the second wavelength inconvertible subnetwork.

Abstract: A signaling system able to improve the efficiency of utilization of network resources and autonomously set a correct spare route, that is, a signaling system setting a path passing through two rings interconnected by a plurality of nodes by signaling wherein each node is provided with an inter-node connection information table including topology information in the network and a branch node judgment unit for judging whether a home node is a branch node based on the content of the inter-node connection information table and wherein when the home node receives a signaling message for setting a working path and it is judged that the node is a branch node, the signaling of the spare path is started for the destination node of the spare path based on the information in the inter-node connection information table so as to autonomous set the spare path.

Abstract: A node in a first ring stores therein connection information about connecting nodes between a second ring and a third ring. Upon receiving a route of a working path by a signaling, the node determines any one of nodes composing the second ring as a branch node. If the working path is not terminated on an end node that the working path ends in the second ring thereon, and also if no node composing the second ring stores therein connection information between the end node and any one of the connecting nodes in the third ring that is connected to the second ring, the node compares each condition of selectable routes of a backup path between the end node and the branch node, and selects any one of the selectable routes as the backup path based on a result of comparison.

Abstract: In a network having a main route and a protection route, a branch node reflects label limit information for the main route into the label limit information for the protection route, and allocates to the main route, a label related to the label for the protection route. On the other hand, a merge node reflects label limit information for the protection route into the label limit information for the main route, and allocates to the protection route, a label related to the label for the main route. Thus, labels having a relation can be allocated to the main route and the protection route.

Abstract: A spanning tree creation unit creates a plurality of spanning trees based on the network topology, and registers the spanning trees to a spanning tree information table. A spanning tree selection unit selects a spanning tree wherein communication resources will be used most effectively, out of the plurality of spanning trees registered to the spanning tree information table. A node setup unit sets the mapping information which expresses correspondence between the requested virtual LAN and the selected spanning tree in each node.

Abstract: An apparatus for calculating a plurality of end-to-end paths communicably connecting two terminal nodes in a communication network divided into a plurality of areas. The apparatus selects, among the plurality of areas, a first sequence of passage areas to be traversed by a first end-to-end path, and selects, among the first sequence of passage areas, multi-path passing areas each defined as an area to be traversed by two or more end-to-end paths. The apparatus further calculates two or more intra-area paths for each of the multi-path passage areas, and determines the first end-to-end path by selecting a first intra-area path among the calculated intra-area paths for each of the multi-path passing areas so that the first end-to-end path includes the selected first intra-area paths as a segment thereof and traverses the first sequence of passage areas.

Abstract: A transmitting apparatus in a network constituted of a plurality of rings connected via a plurality of routes includes a node type determining unit and a backup path setting message transmitting unit. The node type determining unit determines, on receipt of a working path setting message requesting to set a working path, whether the transmitting apparatus is any one of a branch node at which a backup path is branched off from the working path or a merge node at which the backup path merges into the working path. The backup path setting message transmitting unit transmits, when the transmitting apparatus is determined to be a branch node or a merge node, a backup path setting message specifying a route from a ring including the transmitting apparatus to a connection node connecting the ring and a neighboring ring.