Kabushiki Kaisha Toshiba

Toshiba Electronic Devices & Storage Corporation

Yoshimitsu Shimojo

Yasuro Shobatake

Toshiki Kizu

Yoshinori Shigeta

Toshio Okamoto

Hideyuki Ueno

Yasuhiro Katsube

Yoshiharu Uetani

Tadahiro Oku

Yukio Kamatani

Kenji Shirakawa

Tsuguhiro Hirose

Hideaki Nakakita

Mitsunori Omokawa

Takeshi Saito

Jun Hasegawa

Kotaro Ise

Toshitada Saito

Yoshihiro Ohba

Kataro Ise

Kiichiro Oya

A communication device of an embodiment includes a normal operation mode and a low-power consumption mode and includes a first memory unit, a second memory unit, and a control unit. The first memory unit includes a work area for execution of firmware configured to perform basic control of the communication device. The second memory unit stores software for communication with an external device. When transition is performed from the normal operation mode to the low-power consumption mode, the control unit stops voltage supply to the first memory unit and performs control to reduce voltage supplied to the second memory unit to lower than a voltage in the normal operation mode.

Communication device and tire pressure monitoring system

A semiconductor integrated circuit for a radio communication terminal sequentially uses a plurality of frequency channels by instructions from a hopping frequency decision unit to receive packet data by a reception unit. When the integrated circuit cannot detect the head of the packet data in reception operations, the integrated circuit cannot receive packet data should be received originally then assumes that the received packet data is a packet error. And the integrated circuit calculates packet error rates for each frequency channel on the basis of the number of times of reception operations performed for each frequency channel and of the number of times of packet errors to estimate channel qualities by using the packet error rates.

Radio communication device and semiconductor integrated circuit device used for the same

A transmitter has a network interface unit connected to a wireless network capable of transmitting contents for which copyright protection is necessary, an encryption processing unit configured to encrypt contents for which copyright protection is necessary, an RTT measuring unit configured to measure a round trip time after a predetermined packet is transmitted to a receiver, until a response corresponding to the transmitted packet is received, a communication permission determination unit configured to permit transmission of the contents for which copyright protection is necessary when the round trip time measured by the RTT measuring unit is within a predetermined time, and a parameter modification unit configured to change parameters of the wireless network before and/or after the RTT measuring unit performs the measurement of the round trip time.

Receiver, transmitter and communication control program

A radio communication apparatus determines whether a reception signal is received normally. The apparatus measures strengths of the reception signal, assesses frequency channels using a result whether the reception signal is received normally and a strength of the reception signal, and decides that zero or more of the frequency channels as unusable channel in accordance with a result of an assessment of the frequency channels. The apparatus transmits a radio signal using one of the frequency channels sequentially without using the unusable channel.

Radio communication apparatus and radio communication method

A packet switch and a packet switching method capable of taking the full advantage of the transfer capability of the packet switch by avoiding the influence due to the congestion are disclosed. In the packet switch, the priority level according to the congestion states of the transfer target is attached to a packet, and the processing at a time of packet collision is carried out by accounting for this priority level, so that it becomes possible to carry out the packet transfer control according to the congestion status of the transfer target of each packet.

Using priority control based on congestion status within packet switch

A packet processing device is formed by a digest information generation unit configured to extract a plurality of prescribed bit sequences from an input packet, and generate a digest information capable of specifying at least a part of a processing to be applied to the input packet, according to values of the plurality of prescribed bit sequences; and a packet processing unit configured to process the input packet using an instruction sequence to be applied to the input packet that is obtained according to the digest information generated by the digest information generation unit, where the digest information generation unit generates the digest information with respect to a next input packet while the packet processing unit carries out a processing for one packet.

Fast and adaptive packet processing device and method using digest information of input packet

A communication resource management scheme capable of guaranteeing the communication quality with respect to the flow while not requiring the processing for each flow to nodes other than edge nodes is disclosed. The edge node stores an information for obtaining an available amount of communication resources that can be newly allocated in the network to one set of flows which share at least a route from that edge node to an egress node of the network. Then, the edge node carries out an admission control by newly receiving a request for allocation of communication resources for one flow belonging to that one set of flows, judging whether or not to accept the request according to a requested amount of communication resources and the available amount of communication resources as obtained from the information stored for that one set of flows, and allocating requested communication resources to that one flow when it is judged that the request is to be accepted, while the edge node and the core node carry out the priority control.

Communication resource management method and node control device using priority control and admission control

A packet transfer device that can be easily realized even when a number of input ports is large. Each input buffer temporarily stores entered packets class by class, and outputs packets of a selected class specified by the control unit, while the control unit determines the selected class of packets to be outputted from the input buffers according to a packet storage state in the packet storage units of the input buffers as a whole for each class. Each input buffer can temporarily store entered packets while selecting packets to be outputted at a next phase, and the control unit can specify packets to be selected in the input buffers according to an output state of packets previously selected in the input buffers as a whole. Packets stored in the buffer can be managed in terms of a plurality of groups, and each packet entered at the buffer can be distributed into a plurality of groups so that packets are distributed fairly among flows. The packets belonging to one of a plurality of groups are then outputted from the buffer toward the output port. A packet transfer at the buffer can be controlled by issuing a packet transfer command according to a log of packet transfer commands with respect to the buffer and a packet storage state of the buffer.

Packet transfer device and packet transfer method adaptive to a large number of input ports

In respective leaf tables (LT() to LT(m)) of a coupling management table (), there are provided delete operation identifiers (D() to D(m)) indicating that leaf queues (LQ) respectively next to them toward the upstream direction are under delete operation. When one of the leaf queues (LQ(n)) should be deleted, if the leaf queue (LQ(n)) to be deleted stores any element, the delete operation identifier (D(n+1)) is set to 1. Thereby, the leaf table (LT(n&#x2212;1)) can acknowledge that the leaf queue (LQ(n)) is currently under delete operation. Therefore, the coupled packet queue after deletion of the leaf queue and the coupling management table can be maintained consistent.

Packet buffer device and packet switching device

A packet processing device is formed by a digest information generation unit configured to extract a plurality of prescribed bit sequences from an input packet, and generate a digest information capable of specifying at least a part of a processing to be applied to the input packet, according to values of the plurality of proscribed bit sequences; and a packet processing unit configured to process the input packet using an Instruction sequence to be applied to the input packet that is obtained according to the digest information generated by the digest information generation unit, where the digest information generation unit generates the digest information with respect to a next input packet while the packet processing unit carries out a processing for one packet.

Growing community of inventors

Kawasaki, Japan

Yoshimitsu Shimojo