Fujitsu Corporation

Shinichi Sazawa

Hiroaki Kameyama

Yuichi Sato

Yosuke Senta

Daichi Shimada

Masayoshi Hashima

Hiroyuki Higuchi

Tomoyuki Furutono

A communication device that is used in a multi-point communication includes: a receiver, a processor and a transmitter. The receiver receives, from a target communication device included among one or more destination communication devices of the communication device, information that indicates a reception bandwidth allocated to a data transmission conducted from the communication device to the target communication device. The processor calculates a transmission bandwidth to be allocated to the data transmission conducted from the communication device to the target communication device according to information relating to the one or more destination communication devices. The transmitter transmits data to the target communication device at a rate that does not exceed an upper limit transmission rate. The upper limit transmission rate is determined according to a smaller one of values of the reception bandwidth and the transmission bandwidth.

Communication device, communication system and method for controlling communication rate in the communication system

A communication apparatus includes a memory, and a processor coupled to the memory and the processor configured to receive communication data, measure a usable communication band width for communication with a destination apparatus, determine a parameter relating to a reduction ratio for a data amount of the communication data, based on the measured communication band width, reduce the data amount of the communication data, based on the determined parameter, and transmit the communication data of the reduced data amount to the destination apparatus.

Communication apparatus and communication control method

A communication relay device receives a packet transmitted from a first communication device to a second communication device and forwards the packet to a correspondent communication relay device. The communication relay device includes: a processor and a communication processor. The processor extracts, from a request packet that requests a connection to the second communication device, a first identifier for indicating the first communication device, when the communication relay device receives the request packet from the first communication device, and generates configuration information including the first identifier. The communication processor transmits the configuration information to the correspondent communication relay device such that the correspondent communication relay device converts source information of the packet transmitted from the first communication device to the second communication device into the first identifier and forwards the packet for which the source information has been converted to the second communication device.

Communication relay device and communication relay method

A communication device includes a memory and a processor. The processor is configured to extract first division data from transmission data when transmitting the transmission data. The processor is configured to store, as held data, the first division data in the memory in association with first identification information that identifies the transmission data. The processor is configured to transmit, to a communication destination, a first transmission packet including the transmission data and information that identifies the held data to cause the communication destination to store second division data which is not included in the held data, among the transmission data in association with the first identification information. The processor is configured to transmit, when transmitting the transmission data after the transmission of the first transmission packet, a second transmission packet including the first identification information and the held data instead of the transmission data to the communication destination.

Communication device and communication system

A device includes a transmission/reception unit configured to receive a packet transmitted from a communication device to a destination device, a control unit configured to separate data received through the packet into transmission data and control information, a replacement process unit configured to generate replacement data resulting from replacing data associated with an identifier with the identifier in the transmission data when data that has been transmitted toward the destination device in association with the identifier is included, and a transmission unit configured to transfer the replacement data toward the destination device, wherein the control unit generates connected data resulting from connecting respective pieces of data obtained by removing the control information from the data, and discards the control information, and the replacement process unit generates the replacement data by replacing data associated with the identifier with the identifier in the connected data.

Transfer device, communication system and communication method

A relay device includes a first relay device connected to a server and a second relay device connected to a client. The first relay device includes a request unit that requests the server to prefetch data in response to a request from the client; a control unit that caches the data in a first cache; and a notification unit that requests the server to prefetch data in response to a current request from the client, and notifies the second relay device of a predetermined signal when the data matches the data cached in the first cache. The second cache of the second relay device caches a part of the data cached in the first cache. The response unit performs, detecting the predetermined signal, a proxy response to the client with the data cached in the second cache in response to a data request from the client.

Relay device, and relay method

A transfer device includes a memory and a processor configured to, when a plurality of packets are received from a client apparatus, register each of identifiers uniquely identifying each of the plurality of packets into sequence information in a reception order of the plurality of packets, when a first packet is received from the client apparatus, transmit the first packet to a destination apparatus and specify first identifier of a second packet next to the first packet in accordance with an order of the identifiers registered in the sequence information, and transmit the second packet corresponding to the specified first identifier to the destination apparatus.

Transfer device, transfer system, and transfer method

A reception-side apparatus determines whether or not data duplicating a part of received data from a transmission-side apparatus is stored in the first storage that stores first data which has been received, and notifies, when data duplicating a part of the received data is stored in the first storage, the transmission-side apparatus of prediction information on duplicate reception of the first data. A transmission-side apparatus compares, when the prediction information is received, second data to be transmitted and a part of the first data in a second storage that stores the first data which has been transmitted based on the prediction information, determines whether or not there is a first part of the first data matching the second data in the second storage, and transmits, when there is the first part of the first data in the second storage, outline information on the second data.

System and apparatus for removing duplicate in data transmission

A communication apparatus includes a storing unit, a setting unit, a transmitting unit. The storing unit stores the number of transmissions of data to a destination of the data in association with an identifier that identifies the data. The setting unit sets, when the number of transmissions of target data that is data of a target of transmission to the destination reaches a threshold, as alternative data, a combination of the target data and a retaining request for requesting retaining of the target data. The alternative data is data to be transmitted to the destination as an alternative of the target data. The setting unit sets, after transmission of the retaining request, the identifier of the target data as the alternative data. The transmitting unit transmits the alternative data to the destination.

Communication apparatus and method

In an encoding method, data segments and encoding information which indicates encoding patterns each representing a set of data segments used for a predetermined encoding calculation are acquired. An encoded data piece is generated by performing the predetermined encoding calculation based on each encoding pattern, and is stored in the memory. A first encoding pattern for generating the encoded data piece is compared to a second encoding pattern for a next encoding calculation, and the next encoding calculation is performed by using the encoded data piece corresponding to the first encoding pattern when at least a part of the second pattern is common with the first encoding pattern.

Encoding apparatus and encoding method

A network includes first through third communication apparatuses. The second communication apparatus identifies, from packets received from the first communication apparatus, forwarding packets that are packets to be transmitted to the third communication apparatus, and measures the interval in receiving the forwarding packets. The second communication apparatus forwards the forwarding packets to the third communication apparatus. The second communication apparatus receives report information that reports the reception state of forwarding packets from the third communication apparatus, and uses the report information to select target packets that are packets for which success of reception has not been reported from the third communication apparatus in the packets that were forwarded to the third communication apparatus. When the interval in receiving forwarding packets from the first communication apparatus exceeds a threshold, the second communication apparatus retransmits the target packets to the third communication apparatus in a format available for error correction.

Communication method and communication apparatus

An image transmitting method is used to transmit image data from an image transmitting apparatus to an image receiving apparatus. The image transmitting device receives operation events generated in the image receiving device through a network. The image transmitting apparatus calculates a determination time of the image data, in a transmission control based on a previously determined transmission interval, based on an amount of the image data to be transmitted to the image receiving apparatus, information regarding the network through which the image data is transmitted, and a number of the operation events that have been received from an immediately previous transmission time until a time of transmitting the image data. The image transmitting apparatus compares the determination time with a transmission time indicating a time of transmitting the image data, and prevents a transmission of the image data when the determination time is later than the transmission time.

Image transmitting method, program and apparatus

A transfer device allocates, within the range of the maximum communication band of a network that a plurality of groups of applications use in common, a communication band equal to or larger than the minimum band for each of the groups. Furthermore, the transfer device converts, within a communication band allocated to each group, TCP data received from a transmission source of data to UDP data, transfers the UDP data to a transmission destination, and retransmits retransmission data in response to a retransmission request of the UDP data.

Transfer device, and transfer method

A transfer device increments a value of a phase ID at predetermined time intervals, and registers a packet ID of a transmitted data packet and a phase ID on a determination table in an associated manner. When having received a response packet from a receiving-side transfer device, the transfer device determines an unarrived packet on the basis of received packet IDs contained in the received response packet and packet IDs of transmitted data packets. Then, the transfer device determines whether a data packet corresponding to the unarrived packet is lost or on-the-fly from a relationship between a phase ID of the unarrived packet and the maximum phase contained in the received response packet, and retransmits the corresponding data packet only if it is lost.

Transfer device and transfer method

According to an aspect of an embodiment, a method comprises providing a matrix comprising m rows and n columns, each of the rows and columns comprising elements of zero and one, dividing data into n data blocks, associating each of the data blocks with each of the columns, calculating an exclusive-OR of selected data blocks in reference to one of the rows, the selected data blocks being determined by the element of one in the associated columns in the one of the rows, repeating the calculating in other rows and storing separately the calculated data resulting from the exclusive-OR of data blocks in association with the associated rows, respectively.

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Atsugi, Japan

Shinichi Sazawa