Canon Kabushiki Kaisha

Tetsuo Ido

Fumihide Goto

Kazutoshi Hara

Kenichi Fujii

Eiji Imao

A control device for controlling a communication apparatus having a first operation mode in which power with which a network communication function is operable is supplied, and a second operation mode in which power with which an operation of at least part of the network communication function is restricted is supplied, the control device includes a first determination unit configured to determine whether a packet received in the second operation mode is a packet for use in generating an Internet Protocol (IP) address, and a control unit configured to, in a case where the first determination unit determines that the received packet is not a packet for use in generating an IP address, control the communication apparatus not to shift from the second operation mode to the first operation mode.

Control device and control method for controlling communication apparatus

A communication apparatus notifies a partner terminal of delayed acknowledgement (ACK) information, and the partner terminal determines a retransmission time out (RTO) minimum value based on the delayed ACK information. The communication apparatus notifies the partner terminal of the delayed ACK information using a transmission control protocol (TCP) header option at the time of a TCP connection, or using an application. Alternatively, the communication apparatus provides the delayed ACK information for an ACK packet when transmitting a delayed ACK. The partner terminal determines the RTO minimum value in such a manner that the RTO minimum value does not fall below an acquired delayed ACK timer value.

Communication apparatus, method for controlling communication apparatus, and program

In connection establishment processing in TCP communication, a next transmission destination IP address is decided by referring to a routing table. A next transmission destination MAC address associated with the next transmission destination IP address is decided by referring to the ARP table. The transmission destination IP address and the next transmission destination MAC address are stored as the connection management information in a connection management table. A transmission packet is created using the transmission destination IP address and the next transmission destination MAC address which are managed by the connection management information stored in the connection management table.

Communication apparatus, control method therefor, and computer-readable storage medium

An information processing apparatus establishes a proximity wireless link with a partner device and utilizes instantaneous interruptions of the wireless link to control processing of data transfer between the information processing apparatus and the partner device. A control unit in the information processing apparatus determines a frequency of the instantaneous interruptions of the wireless link generated within a predetermined time based on a reception state of a plurality of signals transmitted from the partner device, and controls the processing of data transfer between the information processing apparatus and the partner device according to the determined frequency of instantaneous interruptions.

Information processing apparatus and control method thereof

A method is provided for sending and receiving data between a first processor including a first cache memory and a second processor including a second cache memory via a shared memory. The method includes classifying, by the first processor, a transfer data area that stores data transferred between the first and second processors in the shared memory as a first area filling one cache line and a second area not filling one cache line, copying, by the first processor, data in the second area into a divided data area in the shared memory, the divided data area being aligned with a cache line in the first cache memory, and processing, by the second processor, the data in the first area and the data in the divided data area as data from the first processor.

Methods and systems for inter-processor communication under a multiprocessor environment

Data communication using wireless service discovery is continuously provided even if a radio wave condition temporarily deteriorates or movement of an apparatus occurs. If a temporary deterioration in wireless radio wave environment is found in a communication apparatus including a service discovery function, a search is made again at a raised transmission power. Forcible disconnection processing from a higher-level layer is prevented when communication at the network layer level is ongoing.

Communication apparatus and method providing robust service in the presence of deteriorated radio conditions

A communication apparatus includes a notification unit configured to notify another communication apparatus on a network of the start of a service, a reception unit configured to receive a service join request in response to the notification, a determination unit configured to determine whether to provide the service to the communication apparatus that has transmitted the join request, a transmission unit configured to transmit a service rejection message to a communication apparatus that is determined by the determination unit as a service rejection target, and a re-notification unit configured to re-notify another communication apparatus on the network of the start of the service on the basis of the determination result of the determination unit.

Communication apparatus and method for providing a service to a desired communication device

According to this invention, a wireless communication equipment which communicates with a plurality of nodes supplies an access control technique for improving communication efficiency. For this purpose, a wireless communication equipment is connected to a plurality of networks, and includes a communication unit which sequentially communicates, at a predetermined interval, with devices included in the plurality of network, a determination unit which determinates a communication control parameter of each of the devices when a connection network count changes, a notification unit which notifies the device in the network of the communication control parameter determined by the determination unit, and a communication control unit which controls the communication unit in accordance with the communication control parameter notified by the notification unit.

Wireless communication equipment, wireless communication control method, and program

A terminal determined to be a communication partner in advance is subjected to transmission power control, and another terminal receives data with the maximum transmission power. Data to be transmitted to a plurality of terminals is also transmitted with the maximum transmission power.

Communication apparatus and method

Installation (wired connection) of a function expansion device in a portable information terminal is detected. This detection causes a connection authentication code to be generated. The generated connection authentication code is stored in each of the portable information terminal and the function expansion device via a wire circuit so as to be used for authentication for wireless connection.

Information processing apparatus, function expansion device, and control method therefor

A communication device selects image data to be transmitted to a public network from image data stored in an imaging device, inputs a character string, converts the file name of image data received from the imaging device into the input character string, and transmits the image data to the public network. Upon reception of a request for image data from the public network, the communication device converts the file name of the requested image data into the file name received from the imaging device, and requests transmission of the image data from the imaging device.

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Yokohama, Japan

Tetsuo Ido