Fujitsu Corporation

Masatake Miyabe

Shoichiro Oda

Toru Katagiri

Kazuyuki Tajima

Yutaka Takita

Yasuhiko Aoki

Haruo Yamashita

Tomohiro Shinomiya

Goji Nakagawa

Shinya Kano

Setsuo Yoshida

Satoru Okano

Tomohiro Hashiguchi

Keiji Miyazaki

Atsushi Kitada

Akira Chugo

Shigeru Ishii

Nagao Shimada

Masamichi Kasa

Norihiko Shinomiya

A communication coupling verification method executed by a computer, the communication coupling verification method includes identifying both setting information before a setting change of each of network devices arranged in a network and forwarding information before the setting change; identifying both setting information after the setting change and the forwarding information after the setting change; generating a first model before the setting change and a second model after the setting change by using the setting information before the setting change, the forwarding information before the setting change, the setting information after the setting change, and the forwarding information after the setting change; and determining influence of the setting change on the network based on a difference between the generated first model and the generated second model.

Communication coupling verification method, storage medium, and network verification apparatus

An optical transmission apparatus includes the optical transceiver configured to generate a test light for each wavelength assignable to the wavelength multiplex light to transmit the test light to the optical transmission line via the wavelength multiplexer and demultiplexer, detect a reflected light for the test light from the optical transmission line, calculate an arrival distance of the test light for the each wavelength from the reflected light for the each wavelength, and set a wavelength having a longest arrival distance among the arrival distances for the respective wavelengths, as a wavelength to be assigned to the signal light in the optical transceiver.

Optical transmission apparatus, method for setting wavelength, and optical transceiver

An optical transmission device that is provided at a first site includes: an optical transmitter that transmits a first optical signal that includes first ID information to a second site using a first wavelength; and an optical receiver that receives a second optical signal that includes second ID information and that is transmitted using the first wavelength from the second site. When the first ID information matches the second ID information, the optical transmitter transmits a wavelength report that indicates a second wavelength to the second site using the first wavelength. When the optical receiver receives a completion report that indicates the wavelength report has been received at the second site, the optical transmitter transmits an optical signal to the second site using the second wavelength, and the optical receiver ceases to receive an optical signal of the first wavelength from the second site.

Optical transmission device, optical transmission method and optical transmission system

A transfer device operates within a network including a plurality of transfer devices and a control device. The transfer device includes a processor and a network connecting device. The network connecting device receives a packet. When a packet received from any of the plurality of transfer devices does not satisfy a process condition notified from the control device, the processor performs control such that a request message is not transmitted until a specified time period elapses from reception of the received packet. The request message is a message for requesting the control device to notify the transfer device of a process applicable to the received packet. When process information, which is information representing the process applicable to the received packet, has been obtained by the time the specified time period elapses, the processor processes the received packet in accordance with the process information.

Mitigation of processing load on control device controlling transfer devices within network

There is provided a network management device including a memory in which a change rate of a transmission quality of a first optical signal to be transmitted on a first path with respect to a power of the first optical signal is stored, and a processor coupled to the memory and the processor configured to determine, based on the change rate, whether to set a second path on which a second optical signal transmits to overlap with at least a portion of a route of the first path.

Network management device and network management method

A flow switch stores a plurality of pairs of a protocol message for a communication protocol used in a data plane communication and an identifier of the protocol message. The flow switch applies any one of the stored protocol messages to the data plane communication, and applies an identifier corresponding to a protocol message of a flow control target in the data plane to a control plane communication for a controller.

Flow switch, controller and relay apparatus

An optical transmission characteristic measurement method includes starting transmission of an optical signal from a transmitting node to a receiving node; receiving a bit error rate value measured by the receiving node and relates to the optical signal; determining whether the bit error rate value is higher than a given threshold; adjusting input power of the optical signal to lower until it is determined that the bit error rate value is higher than the given threshold when it is determined that the bit error rate value is not higher than the given threshold; estimating an optical signal to noise ratio from the bit error rate value when it is determined that the bit error rate value is higher than the given threshold; and calculating an optical signal to noise ratio based on the estimated optical signal to noise ratio and an amount of lowering of the input power.

Optical transmission characteristic measurement device and method

A communication apparatus configured to communicate with a router included in a first network and a multiplexer that multiplexes a plurality of optical signals having different wavelengths transmitted from the communication apparatus, the communication apparatus comprising a memory, and a processor coupled to the memory and configured to transmit and receive a first signal to and from the router, transmit and receive a second signal to and from another communication apparatus in a second network through the multiplexer, the second signal having a transmission scheme different from the first signal, mutually convert the first signal and the second signal with each other, detect a first communication disabled state between the another communication apparatus and the communication apparatus, and transmit, to the router, a first detection signal for detecting adjacency relationship between the communication apparatus and the router when the first communication disabled state is detected.

Communication apparatus, method of communication and communication system

There is provided an apparatus configured to estimate optical transmission performance in a transmission path of an optical signal, the apparatus including a memory, and a processor coupled to the memory and the processor configured to acquire a first index related to a first transmission performance of an optical signal transmitted through a span group between a first node and an n-th node and a second index related to a second transmission performance of an optical signal transmitted through a span or a span group between the first node and an m-th node, wherein n is an integer of 3 or more, and m is the integer satisfying m&#x3c;n, and estimate a third index related to a third transmission performance of an optical signal to be transmitted through a span between the m-th node and the n-th node, based on the first index and the second index.

Apparatus and method for estimating optical transmission performance

A transmission device is used for a network that includes a plurality of working paths and a plurality of protection paths bypassing a relevant working path for each working paths. The transmission device includes a data plane unit that transmits and receives data to and from other transmission devices; and a signaling processing unit that performs switching, when a signaling message requesting activation to switch to a first protection path corresponding to a first working path is received, from the first working path to the first protection path, wherein, when the first working path is configured as a subset of a second working path and a second protection path corresponding to the second working path is provided, the signaling processing unit performs switching from the first working path to the first protection path and performs switching from the second working path to the second protection path.

Transmission device, network designing device, activation method, and network designing method

A frame transmission system includes: a first frame transmission apparatus configured to transmit a message frame containing an medium access control (MAC) destination address in an intended user MAC frame, and containing both MAC header information and header information of an upper layer in a user MAC frame; and a second frame transmission apparatus configured to identify one output destination physical link based on the MAC header information and the header information of the upper layer acquired from the message frame, when an output destination with regard to the MAC destination address in the message frame constitutes a link aggregation group including a plurality of physical links, and generate a reply frame containing information on the identified output destination physical link and a MAC address of the second frame transmission apparatus in order to return the reply frame to the first frame transmission apparatus.

Frame transmission system, frame transmission apparatus, and frame transmission method

An apparatus serves as a node in a network on which plural working paths and plural protection paths for bypassing the plural working paths are set, where the plural protection paths share bandwidths allocated thereto. The apparatus includes a data plane unit functioning as an interface that transmits and receives data with a node in the network. The apparatus predicts a first working path having a highest probability that a failure is likely to occur, among the plural working paths, based on transmission qualities of the plural working paths. The apparatus beforehand sets, to the data plane unit, a setting value for a first protection path corresponding to the first working path, and validates the setting value set to the data plane unit, based on a request for activating the first protection path, when the first working path is switched to the first protection path.

Apparatus and method for switching a communication path

A transmission device includes a memory which stores a program, and a processor which executes, based on the program, a procedure including calculating a difference between a first time when a frame is received by a first port which is in a blocked state and a second time when the frame is received by a second port which is not in a blocked state, and correcting a frame received after topology of a network is changed in accordance with states of the first and second ports after the topology is changed and the difference.

Transmission device, transmission method, and computer-readable recording medium

A provider edge apparatus comprises an ingress processing unit to generate an encapsulated frame to be transmitted to another provider edge apparatus coupled to another customer edge apparatus, wherein the encapsulated frame includes a frame directed to the another customer edge apparatus, an egress processing unit to extract a frame to be forwarded to the specified customer edge apparatus, a storage to store an identifier of the provider edge apparatus and an identifier of the another provider edge apparatus when the specified customer edge apparatus is coupled to the another edge apparatus via a second access line, wherein the identifiers corresponds to a group identifier indicating an access line group belonging the first access line and the second access line, and a filter to discard the encapsulated frame or a frame in the encapsulated frame satisfying a filter condition.

Provider network and provider edge apparatus

A frame transmission device includes: a clock section; a path control section to switch a plurality of transmission paths for exchanging a time synchronization frame with a node device that measures a reference time; a fluctuation estimation section to set a fluctuation estimate of a transmission delay of the time synchronization frame on each of the plurality of transmission paths; and a time synchronization section to synchronize the clock section to the reference time in accordance with a time synchronization frame exchanged on a selected transmission path selected from among the plurality of transmission paths based on the fluctuation estimate.

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Kawasaki, Japan

Masatake Miyabe