Fujitsu Corporation

Masakazu Bamba

Koji Takeguchi

Katsuhiro Shirai

Yasuko Nozu

Jun Wakabayashi

A wavelength-selective device includes: a storage in which a wavelength management table is stored; and a processor configured to execute a procedure, the procedure including: searching for one or more paths used as a new path having a first ending time in a network, based on the wavelength management table; selecting a wavelength having a second ending time closest to the first ending time, from one or more wavelengths used on paths found by the searching; and configuring a path using the selected wavelength as the new path.

Wavelength selective device, wavelength selective method, and wavelength selective system

A node positioned in a protection path for a working path stores identification information available to identify a source node and an end node. The identification information is contained in a signaling message transmitted to the end node through the protection path from the source node in order to set a usage reservation of the protection path. The node notifies the failure detection to an address identified by the stored identification information in response to a failure detection of the protection path.

Communication system and node

A protection channel provisioning method includes: reserving a first protection channel corresponding to a first work channel and a second protection channel corresponding to a second work channel; provisioning a shared protection channel by configuring a circuit of node equipment provided on a shared route on which the first protection channel and the second protection channel are redundantly reserved so that a data signal of the first work channel or a data signal of the second work channel is transmitted via the shared route; and configuring a circuit of branch node equipment provided in a branch node at which the shared protection channel is guided to a first node corresponding to the first protection channel and a second node corresponding to the second protection channel so that the data signal transmitted via the shared protection channel is not guided to the first node and the second node.

Protection channel provisioning method and node equipment

The communication method and the subsidiary transmission apparatus for a point-to-multipoint communication system in which the subsidiary transmission apparatus autonomously establishes point-to-multipoint communication between one main transmission apparatus and multiple subsidiary transmission apparatuses, without manually operating switches of the subsidiary transmission apparatuses. The subsidiary transmission apparatus generates, during the absence of a transmission request to the main transmission apparatus, an alarm signal to be transmitted to the main transmission apparatus through an upstream line, and the main transmission apparatus sends, while receiving the alarm signal through the upstream line, a specified notification signal, which is to be sent out in response to the reception of the alarm signal, to a downstream line, and the subsidiary transmission apparatus evaluates the state of use of the upstream line depending on the presence or absence of reception of the notification signal from the downstream line.

Communication method for point-to-multipoint communication system and subsidiary transmission apparatus for the same system

A disclosed communication apparatus includes a protocol processing unit configured to send and receive link information on a link in a network having a redundant configuration according to a protocol, to build topology information of the network from the link information, and to set up a path in the network based on the topology information. The protocol processing unit includes a link information advertising unit configured to advertise the link information including, for each of protection types of the link, information used to set up the path, a topology information storing unit configured to store the topology information, and a link information receiving unit configured to receive the link information and to store the received link information in the topology information storing unit.

Communication apparatus and protocol processing method

There is provided a communication device including a score information storage unit to store score information indicating a score as an evaluated value of a communication path; a receiver unit to receive a route connection notice including current score information; a routing unit to acquire the score information stored in the score information storage unit, and select the communication path next to the communication path based on the acquired score information of the communication path; a score updating unit to add a score of the communication path selected by the routing unit to the current score of the partial communication route indicated by the current score information, and update the current score information to the added score as a new current score; and a transmission unit to transmit the route connection notice including the current score information.

Communication device, system and method to form communication route

Two path setting sides are determined between a pair of nodes in a network, and two path setting messages are created. The two path setting messages each includes information on a path switch default direction, a wait-to-restore timer value, and a mode identifier identifying a revertive mode. Then the two different communication paths are concurrently set between the pair of nodes by transmitting concurrently the created two path setting messages between the pair of nodes. In the case of the revertive mode, a communication path set on a side identified by the path switch default direction is operated as a working path either in an initial state or when no faults have occurred during a time period indicated by the wait-to-restore timer value after recovery of the fault on the first side.

Method and apparatus for setting communication paths in a network

A management network for managing networks managed individually by a plurality of groups, wherein authorization and unauthorization of access for supervision and control are automatically set. Each network element is assigned a TID, as a prefix, having a group ID identifying a group to which the network element belongs. Topology information considered from each network element to all network elements includes a group ID. When a group ID included in the received topology information matches the prefix of the TID assigned to its own network element, the source is registered at the authorized side of the access authorization list (step), while when it does not match, it is registered at the unauthorized side (step).

Management network for network management, its management method, and network element used therefor

The present invention provides a line accommodation device comprising at least one first communication control unit for controlling information transmission/reception to/from a first communication system, at least one second communication control unit for controlling information transmission/reception to/from a second communication system using the first communication system as a communication medium and a route control unit for controlling the switching of an information transfer route between the first and second communication unit.

Line accommodation device and control method thereof

A communication apparatus, in a communication network in which a plurality of routes can be set with respect to a destination, acquires a line condition of a communication line in each route, calculates a communication cost of each route, based on the line condition of the communication line in the route, and selects a route from the plurality of routes based on the communication cost calculated. The line condition is acquired at regular intervals to thereby update the communication cost.

Method of and apparatus for communication, and computer product

A transmission apparatus including: a plurality of asynchronous network interface units each having an asynchronous network termination unit for inputting/outputting a packet from/to an asynchronous networks and a mapping unit for converting the packet into a first synchronous frame and vice versa, a plurality of synchronous network interface units each used for inputting/outputting a second synchronous frame from/to a synchronous networks, a buffer provided on at least a first of the asynchronous network interface units, and a control unit for storing a packet output by the asynchronous network termination unit for accommodating a specific asynchronous networks and a packet output by the asynchronous network termination unit of the first asynchronous network interface unit into the buffer by adding identifiers for identifying the asynchronous network termination units in the event of a line failure occurring in a synchronous networks on a route related to the specific asynchronous network.

Transmission apparatus

A communication apparatus that, in sending and receiving data between a LAN and a certain network, dynamically sets the capacity of a line used for sending and receiving data via the network based on the amount of use of a line used for sending and receiving data via the LAN, and a method for setting the line capacity thereof are disclosed.

Communication apparatus and method for setting line capacity thereof

A high-speed communications system which permits high-speed communication services to be implemented with minimum modification to the existing communications facilities. A multiplexer/demultiplexer unit multiplexes outgoing signals to a network and demultiplexes incoming signals from the network separately for voice and data signals. A first voice processing unit, being linked to a voice service subscriber who only uses voice communication services, processes voice signals for bidirectional communications over a subscriber line. A second voice processing unit, being linked to a voice/data service subscriber who uses both voice and data communication services, processes voice signals for bidirectional communication. An office-side modem unit has modulator/demodulator functions to support high-speed bidirectional data communication for the voice/data service subscriber. An office-side splitter splits incoming signals from the voice/data service subscriber into separate voice and data signals. A subscriber-side splitter, coupled to the office-side splitter through the subscriber line, separates the voice signals and the data signals. A subscriber-side modem unit processes data signals to support high-speed bidirectional data communication.

Growing community of inventors

Kawasaki, Japan

Masakazu Bamba