Abstract: A wireless communication device includes: a transmission unit; a carrier sense unit; a transmission time calculating unit that estimates a necessary transmission time taken from start to completion of the transmission of the wireless frame; a time-out time calculating unit that calculates a time-out time from the predetermined time period and the necessary transmission time; a frame transmission determining unit that compares a carrier detection time during which a carrier notified from the carrier sense unit is detected with the time-out time to determine whether to transmit or discard the wireless frame; and a control unit that, based on the determination result notified from the frame transmission determining unit, (i) notify the transmission unit that the wireless frame is to be transmitted when it is determined to transmit the wireless frame, and (ii) discard the wireless frame when it is determined to cancel the wireless frame.

Abstract: A transmission success probability calculator (114) calculates a transmission success probability that is a probability of receiving an ACK frame from another wireless communication device during a preset first reference period after transmission of an inspection frame, the inspection frame being transmitted multiple times to another wireless communication device. A transmission attempt possible count calculator (115) calculates a transmission attempt possible count of the inspection frame during a second reference period. A timeout occurrence rate calculator (116) calculates, from the transmission success probability and the transmission attempt possible count, a timeout occurrence rate that is a probability of not receiving the ACK frame from the wireless communication device even through the inspection frame is repeatedly transmitted by the transmission attempt possible count within the second reference period.

Abstract: A configuration in which a device server is connected to a client and is also locally connected to a USB device suppresses data transfer volume fluctuation due to network delay, maintains the data transferring volume at a value guaranteed by the isochronous output transfer and improves network robustness under the isochronous output transfer process. The device server includes a data buffer portion for the isochronous output transfer data and performs advance reading of the isochronous output transfer data after sending back a transfer completion response unconditionally to the client upon receiving an isochronous output transfer request from the client. When the retention data volume in the data buffer portion reaches the upper limit threshold, the transfer data buffered in the data buffer portion is transferred to the device over the isochronous output transfer.

Abstract: A network device operating in a configuring mode and a normal operational mode includes: a configuration parameter memory; a network interface; a dynamic address generating unit that generates two logical addresses, when a DHCP request is received in the configuring mode, and returning one logical address to a transmission source of the request and assigning the other to the network device; a name resolving unit that transmits, when a name resolving request is received in the configuring mode, a logical address of the network device to the transmission source regardless of the name; and a parameter setting unit storing a parameter value transmitted, after the logical address of the network device is transmitted by the identifier resolving unit to the transmission source, using the logical address by said transmission source. In the normal operational mode, a network function is realized using parameters in the memory.

Abstract: Methods and systems are provided for helping maintain isochronous communications with peripheral devices (308), such as USB devices, over a network (302). Some methods for facilitating isochronous IN communication include noting (1906) passage of a predetermined interval without communication (310) from the peripheral device driver (402), and then creating (1908) a dummy communication (312) and sending (1910) it over the network toward the peripheral device to maintain isochronous communication toward the peripheral device. Some methods for facilitating isochronous OUT communication include noting (2006) passage of a predetermined interval without receipt, over the network, of a responsive communication (310) from the peripheral device in response to a first communication, and then creating (2008) a dummy communication (312) and sending (2010) it toward the peripheral device driver to maintain isochronous communication transmissions toward the peripheral device driver.

Abstract: Methods and systems are provided for helping maintain isochronous communications with peripheral devices (308), such as USB devices, over a network (302). Some methods for facilitating isochronous IN communication include noting (1906) passage of a predetermined interval without communication (310) from the peripheral device driver (402), and then creating (1908) a dummy communication (312) and sending (1910) it over the network toward the peripheral device to maintain isochronous communication toward the peripheral device. Some methods for facilitating isochronous OUT communication include noting (2006) passage of a predetermined interval without receipt, over the network, of a responsive communication (310) from the peripheral device in response to a first communication, and then creating (2008) a dummy communication (312) and sending (2010) it toward the peripheral device driver to maintain isochronous communication transmissions toward the peripheral device driver.