Fujitsu Corporation

Toshio Soumiya

Koji Nakamichi

Naotoshi Watanabe

Masafumi Katoh

Takeshi Kawasaki

Michio Kusayanagi

Kenya Takashima

Shunji Abe

Sho Shimizu

Akiko Yamada

Satoshi Imai

Shinji Yamashita

Yutaka Ezaki

Hiroshi Yamamoto

Yoshihiro Watanabe

Shinya Kano

Yuji Kato

Satoshi Kakuma

Tomohiro Ishihara

Masato Okuda

Takashi Hatano

Kenichi Kawarai

Akira Chugo

Jyoei Kamoi

Toshio Shimoe

Hichiro Hayami

Haruo Mukai

Toshiyuki Sudo

Tetsuya Nishi

Keiichi Nakatsugawa

Junichi Yamazaki

Yoshiharu Sato

Ichiro Iida

Norihito Nishimoto

Kenji Hikichi

Kazuo Sakagawa

Kazunori Murata

A network control apparatus is configured to detect connection relationships among a plurality of network switches in a communication network. The network control apparatus transmits a control signal to a first network switch, where the control signal commands the first network switch to transmit a first topology detection signal from a first plurality of ports provided for the first network switch. The network control apparatus receives, from a second network switch that has received the first topology detection signal, a response signal including topology information that has been detected by the second network switch from the first topology detection signal, and, based on the topology information included in the response signal, controls selection of a target port, via which to transmit a second topology detection signal, from among a second plurality of ports provided for the second network switch.

Apparatus and method for detecting connection relationships among switches in a communication network

A control apparatus includes a generation unit to generate a plurality of entries to be supplied with the switch, the plurality of entries being stored in a storage, a transmission unit to transmit to the switch an integration entry that the plurality of entries is integrated in an integration rule, the switch storing the plurality of entries in a table used for processing input packets, an acquisition unit to acquire the plurality of entries from the storage, and a control unit to perform re-integration processing including generating a re-integration entry integrated the plurality of entries and an additional entry in a re-integration rule created based on content of the plurality of entries and the additional entry, the re-integration entry being transmitted to the switch.

Control apparatus and method for supplying switch with entry

A transfer device in a network including a plurality of control devices includes a network connection device, memory, and a processor. The network connection device communicates a target packet as a target of a transferring process. The memory stores a transfer rule received by the network connection device from a determination device as a control device for determining a transfer rule indicating a method of a process performed by the transfer device. The processor judges whether or not disable information indicating that the transfer rule is not to be acquired from the determination device when a transfer rule applicable to the target packet is not stored in the memory is included in the target packet. When the disable information is included, the processor outputs the target packet to the network connection device without requesting the transfer rule. The network connection device transmits the target packet to another transfer device.

Transfer device, control device, and transfer method

An OpenFlow switch used in an OpenFlow network including a plurality of OpenFlow switches and an OpenFlow controller configured to control the plurality of OpenFlow switches includes: a failure detector configured to detect a failure of a link connected to the OpenFlow controller; and a channel management unit configured to establish an OpenFlow channel to transmit control information to the OpenFlow controller through another OpenFlow switch among the plurality of OpenFlow switches when a failure is detected by the failure detector.

Openflow switch and failure recovery method in openflow network

The processor obtains a process time, which is a time taken for processing a control message when the control device requests that a target processing device, selected from among the plurality of processing devices, process a control message. When the process time has become longer than a first threshold, the processor determines which of a first and a second congestion has occurred based on whether the process time has become longer than a second threshold, which is greater than the first threshold. The first congestion occurs in the transfer devices used for a communication between the control device and the target processing device. The second congestion occurs in the target processing device. The network connection device transmits a request message requesting that a transfer route for which it has been determined that the control message is not processed in a device in which the congestion has occurred be set.

Route determination apparatus and transfer route determination method

A network control apparatus includes: a power consumption collecting unit configured to collect power consumption information measured by at least one electrical node included in an electrical layer network and at least one optical node included in an optical layer network; a cut-through range identifying unit configured to calculate an optical cut-through path based on the collected power consumption information; and a cut-through path setting instructing unit configured to instruct the electrical node and the optical node to set the optical cut-through path based on the calculation result in the cut-through range identifying unit.

Network control apparatus, network control system, and network control method

A video quality monitoring method includes a distribution server measuring first video quality index values according to a full-reference method by comparing a video, distributed from the distribution server to a client through a network, with a degraded video, generated by causing multiple scenarios of quality degradation due to the network in the video in a pseudo manner, creating characteristic data of first quality degradation values, obtained by causing the quality degradation to vary with the scenarios at regular intervals, and the first video quality index values corresponding to the respective scenarios, and transmitting the characteristic data to the client; and the client measuring a second quality degradation value in the video distributed through the network, and calculating a second video quality index value, equivalent to a value according to the full-reference method, of the distributed video from the measured second quality degradation value and the characteristic data.

Video quality monitoring method, distribution server, and client

A recovery-path request message control block generates, sends, and receives a recovery-path request message containing failure location information and recovery-path setup information. A label assignment message control block generates, sends, and receives a label assignment message. A setup label information generation block generates setup label information. A recovery-path label table management block constructs and manages a recovery-path label table. A failure detection block detects the location of a failure. A failure notification message transfer block transfers a failure notification message containing failure location information. A recovery-path establishment block establishes a recovery-path by comparing failure location information contained in a failure notification message and failure location information contained in a recovery-path label table and by selecting setup label information corresponding to matching failure location information.

Transmission apparatus with mechanism for reserving resources for recovery paths in label-switched network

A method of detecting a failure in a network, which includes a transport plane comprised of a plurality of communication nodes performing optical cross-connect and a control plane comprised of a plurality of control nodes that are connected to and control the respective communication nodes, includes the steps of transmitting, from a control node connected to a communication node having detected a failure to an adjacent control node, a failure information message having a time indication indicative of a time at which the failure is detected, and identifying, at a given control node which received the failure information message, a location of the failure in response to the time indication.

Method of and control node for detecting failure

There is disclosed a transmitting system which is capable of recovering a fault efficiently, thereby improving transmission quality. When a fault has occurred, a fault message-sending section notifies a fault message including information of a detected location of occurrence of the fault to other devices. A relay/transfer section carries out label switching operation on a packet having a label added thereto and relay/transfer of the packet. The integer calculation section performs a function operation based on flow information of an input packet to calculate one integer corresponding to one input packet. A path-setting section classifies the calculated integer into one of sections divided by boundary values and sets the section as a path for transferring the input packet. Further, the path-setting section adjusts the boundary values, when a fault message is received, or depending on the state of communication. An ingress edge transfer device adds a label to a packet for transferring the packet via the set path.

Transmission system and transmitting device

The present invention relates to distributing the load between the set routes among a plurality of routes between a communication apparatus which serves as a start point to another communication apparatus which serves as an end point. An apparatus provided in a router in a network collects traffic characteristics of transmission paths connected to the router, notifies other routers of the collected traffic characteristics, calculates load based on the collected traffic characteristics, decides based on the calculated load information whether or not a transmission path should be added or deleted, and equalizes the load among the plurality of transmission paths.

Transmission path controlling apparatus and transmission path controlling method as well as medium having transmission path controlling program recorded thereon

The present invention provides a traffic information collecting device and method. A node in a communication network collects a first traffic information of a first link connected to an own node. And also the node receives second traffic information of second links connected to the other nodes. The second traffic information is transmitted from the other nodes. The node stores the first and second information. In consequence, the node can be informed of the conditions of the traffic of each link in the communication network based on the stored information. As the result, it becomes possible to control the load sharing in correspondence to the conditions of the traffic.

Device and method for collecting traffic information

An L bit for notifying another router of whether a self-router belongs to a connection-oriented network is newly provided in the options field of a conventional OSPF packet and the OSPF packet, including L bit is transmitted to another router. In this way, each router belonging a network can automatically recognize a router belonging to a connection-oriented network by detecting L bit. Then, by generating a routing tree, a connection-oriented network device can be identified in the routing tree and mapping between a connection-oriented network and a connectionless network can be performed in an edge device.

Routing information mapping device in a network, method thereof and storage medium

A packet flow control apparatus performing flow control of packets each having variable length, includes: a buffer memory for temporarily accumulating arrived packets until a sending time of each packet; a counter updated based on a rate determined in accordance with a packet length calculated by a counter value of the counter and limited flow of packets; a sending time determining section for determining the sending time of each packet based on the counter value and a present time; and a sending order control section for managing a sending order of each packet accumulated in the buffer memory, and for sending a read instruction of each packet to the buffer memory, based on the sending time determined by the sending time determining section.

Growing community of inventors

Kawasaki, Japan

Toshio Soumiya