Fujitsu Corporation

Nami Nagata

Shigeki Fukuta

Jun Kakuta

Ai Yano

Hideki Mitsunobu

Takao Mohri

Yuki Nishiguchi

Kazuo Sasaki

Ryuichi Matsukura

Makoto Kubota

Noriyuki Fukuyama

Hitoshi Ueno

Nobutsugu Fujino

Shinichiro Mori

Masahiro Hara

Jun Ibuki

Masanori Yamazaki

Kentaro Ikemoto

Takashi Enami

Yukio Hirokawa

Keitaro Ohno

A communication apparatus that transmits and receives packet data by radio communication with another communication apparatus, the communication apparatus including a memory; and a processor coupled to the memory and the processor configured to: receive first packet data in a first packet transmission period; calculate data collection efficiency indicating a ratio of a reception data amount of the first packet data, to a transmission data amount of the first packet data, based on received the first packet data, and measure a first radio quality in a radio section between the communication apparatus and the other communication apparatus, based on received the first packet data; calculate a packet length and transmission count of the first packet data, based on the data collection efficiency and first radio quality; and transmit a second packet data including the packet length and transmission count.

Communication apparatus, communication system, and communication control method

A distribution process system includes a first terminal configured to, in accordance with a change relating to a processing load, perform transmission of first information relating to the processing load of the first terminal to a second terminal having a transmission frequency of a message relating to a processing load of the second terminal to a management device higher than a transmission frequency of a message relating to the processing load of the first terminal, the second terminal configured to, in response to receiving the first information, transmit to the management device a first message relating to the processing load of the second terminal and the first information, and the management device configured to manage a load state of each of the first terminal and the second terminal, and update the load state of the first terminal in accordance with the first information in response to receiving the first information.

Distribution process system and distribution process method

An information processing device includes a memory and circuitry coupled to the memory and configured to determine, when execution of a process on data is canceled in accordance with a cancellation request from a source that has requested the process, whether the process is to be executed and whether a result of executing the process is to be stored, based on a processing rate of the process by the information processing device.

Data process execution device, storage medium, and data process execution system

A communication control apparatus includes: a processor configured to: fix a number of sets of data to be inserted into one packet by a communication apparatus according to a wireless quality with the communication apparatus; and notify the communication apparatus of the number of sets fixed at the fixing.

Communication control apparatus, communication control system, communication control method, and recording medium

A gateway which is an example of a communication device includes a selecting unit and a management data collecting unit. The selecting unit selects a collection manipulation within a range not exceeding a resource amount allocated to transmission of management data among all resources of wireless communication usable by a device in accordance with an evaluation value. The evaluation value is a value calculated on the basis of a contribution degree to failure analysis and consumption resources for each of a plurality of collection manipulations for collecting management data used for the failure analysis from a device. The management data collecting unit executes the collection manipulation selected by the selecting unit on the device and collects the management data corresponding to the collection manipulation from the device through the wireless communication.

Communication apparatus, data processing system, and communication method

A radio communication anomaly detecting method includes: gathering and storing different kinds of parameters indicating a radio quality with a sensor node in a storage unit; classifying parameter sets, each containing specific kinds of parameters gathered during a prescribed time period among the stored parameters, into clusters; estimating that a rapid radio quality degradation has occurred during the prescribed time period when there is a cluster of which all average values of specified kinds of parameters among the different kinds of parameters degrade more than those of another cluster; and performing a trend analysis for a time period during which it is not estimated that the rapid radio quality degradation has occurred to determine whether each of the different kinds of parameters gathered during the time period exhibits a trend of degradation, and estimating that a slow radio quality degradation has occurred based on a result of the trend analysis.

Method and device for detecting radio communication anomalies

An interruption cause determination device comprising: acquiring in the memory a radio wave reception strength (RWRS) and a packet error rate (PRE) of a wireless link, and estimating a characteristic curve of the PRE against RWRS that passes through a point corresponding to a combination of values of the RWRS and the PRE at a first point in time a specific amount of time earlier than a second point in time at which the acquired PRE of the wireless link reached a threshold value or greater, under the assumption that the interference power at the first point in time is maintained; and determining the cause of interruption based on a positional relationship of a point corresponding to a combination of values of the RWRS and the PRE at the second point in time, with respect to the estimated characteristic curve of the PRE against RWRS.

Interruption cause determination device, interruption cause determination method, and recording medium stored with an interruption cause determination program

A congestion control method is used in a wireless network that includes a plurality of wireless communication equipments. The method includes: monitoring a congestion condition in respective wireless communication equipments; and extending an exclusive transmission time in which a packet is transmitted exclusively using wireless resource of the wireless network in a congested wireless communication equipment in which congestion has occurred among the plurality of wireless communication equipments.

Congestion control method and wireless communication equipment

A wireless communication device comprising: a storage configured to store identification information identifying a particular adjacent device from among the plurality of wireless communication devices that is adjacent to the wireless communication device and that transmits, to the wireless communication device, data addressed to a final destination device; a generator configured to generate search data that includes information indicating a search of a route to the final destination device; a transmitter configured to broadcast the search data to adjacent devices; and a decision unit configured to determine that a bypass route from the particular adjacent device to the final destination device is not present when data that includes information indicating that the search data does not reach the final destination device is received from all particular adjacent devices for which identification information is stored in the storage.

Wireless communication device and method for searching for bypass route in wireless network

A multi-hop wireless network monitor method for monitoring a state of a multi-hop wireless network including a plurality of nodes, the method includes: transmitting a packet that stores monitor data indicating a state or performance of a first node and identification information that identifies the first node; rewriting the monitor data stored in the packet with the monitor data detected by a second node and rewriting the identification information stored in the packet with the identification information that identifies the second node in the second node when the monitor data detected by the second node is worse than the monitor data stored in the packet; and specifying a node in the worst state or performance in a propagation route of the packet according to the identification information stored in the packet.

Monitoring method of multi-hop wireless network

A wireless communication network system includes: a location estimation device includes: a processor; and a memory which stores a plurality of instructions, which when executed by the processor, cause the processor to execute: collecting information, for each wireless device in a pair of wireless devices communicating with each other in the wireless communication network, as to the number of occurrences of duplicate reception caused by the data retransmission performed when the reception acknowledgement does not reach the transmitting wireless device; and estimating the location of an interference source of radio wave in a wireless communication network based on the collected information as to the number of occurrences of duplicate reception such that the location of the interference source is closer to one of wireless devices in the pair with a less number of occurrences of duplicate reception than to the other one of the wireless devices in the pair.

Location estimation device and location estimation method for estimating location of interference source

A gateway apparatus that connects a multi-hop network of tree structure formed of node apparatuses to other network, comprising a grouping unit that groups, for each representative node apparatus having a direct link to the gateway apparatus in the tree structure, the nodes belonging to a subtree having same representative node as a root, into a node group, an interference group specifying unit that specifies a node group in which packet communication in the node group is subjected to an interference of a degree exceeding a threshold as an interference group, and a slot allocation unit that allocates some one time slot among a plurality of time slots included in a frame to one interference group among a plurality of interference groups, and allocates another time slot among the plurality of time slots to another interference group among the plurality of interference groups.

Gateway apparatus, node apparatus, communication system, control method and computer readable medium

A communication terminal performs wireless ad hoc communication with another terminal via a first wireless interface dedicated to reception and a second wireless interface for both transmission and reception. The terminal executes defining a communication area to be divided into cells of first polygonal shapes and each of the cells to be divided into a plurality of sub-cells of second polygonal shapes different from the first polygonal shapes; allocating, so as to prevent adjacent cells from belonging to a set of two identical wireless channels, a first wireless channel and a second wireless channel as the set of wireless channels to the cells; and setting the first wireless channel and the second wireless channel so that the same transmission channel is set for sub-cells brought into contact between the adjacent cells while different transmission channels are set for adjacent sub-cells in an own cell where an own terminal is present.

Wireless ad hoc communication system

A VPN server encapsulates a packet Pupon receiving the packet and distributes packets P (-) and P (-) to wireless terminals MNand MNrespectively. The wireless terminal MNdecapsulates the packet P (-) (as packet P-) upon receiving the packet and transmits the packet P-to a wireless terminal MN. Thus, the packet is transmitted by a communication path: file server&#x2014;VPN server&#x2014;wireless terminal MN&#x2014;wireless terminal MN. The wireless terminal MNdecapsulates the packet P (-) (as P-) upon receiving the packet and transmits the packet P-to the wireless terminal MN. The packet P-is transmitted by a communication path: file server&#x2014;VPN server&#x2014;wireless terminal MN&#x2014;wireless terminals MN

Routing control method and system

A radio communication apparatus including: a receiver receiving a traffic evaluation index value of a contention node as a connection node one layer below a self node with a root node of a radio network set as the top layer; parameter determining unit determining a parameter related to priority control of the contention node or a priority for determining the parameter, based on the traffic evaluation index value of the contention node, so that a traffic congestion is prevented and cleared; and a transmitter transmitting the parameter related to the priority control of the contention node or the priority to the contention node.

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Kawasaki, Japan

Nami Nagata