| Patent application number | Description | Published |
| 20080205651 | Secure processor system without need for manufacturer and user to know encryption information of each other - A secure processor system capable of improving the security of processor processing by the addition of minimum modules without the need for a manufacturer and a user to know encryption information of each other has been disclosed. The secure processor system includes a secure processor having a CPU core that executes a instruction code, an encryption key hold part that holds a processor key, and an encryption processing part that encrypts or decrypts data input/output to/from the core with a processor key and a memory, and the encryption key hold part includes a hardware register that holds a hardwired encryption key, a write only register that stores an encryption key for instruction to be input and holds the stored encryption key for instruction so that it cannot be read, and the encryption key hold part outputs a hardware encryption key as a processor key at the time of activation and outputs a command encryption key as a processor key after a encryption key for instruction is written. | 08-28-2008 |
| 20080219435 | Information transmitting apparatus, information transmitting method, and computer product - An information transmitting apparatus encrypts and transmits transmit data that includes contents for which transmission instruction has been received, an authentication code, and padding. The information transmitting apparatus includes a padding calculating unit that calculates a size of the padding based on an encrypting algorithm, a size of the authentication code and a size of the contents; a transmit-data size calculating unit that calculates a size of the transmit data from the size of the padding, the size of the authentication code, and the size of the contents; a generating unit that generates, using the size of the transmit data, a header that indicates a type of the transmit data and the size of the transmit data; an encrypting unit that encrypts the transmit data; and a transmitting unit that transmits the header and the encrypted transmit data. | 09-11-2008 |
| 20100031016 | PROGRAM METHOD, AND DEVICE FOR ENCRYPTION COMMUNICATION - An encryption communication method for performing communication that includes a data transfer phase for transmission of content data and a handshake phase for user authentication or agreement on the transmission method for content data, the method comprising: storing one set of a plurality of content data for multiple users in a common transmission communication region provided for the multiple users; transferring the stored one set of the plurality of content data during the data transfer phase when transferring content data of the multiple users to a communication target device; and receiving the stored one set of the plurality of content data using a plurality of transmission-reception communication regions provided for each of the multi users is provided. | 02-04-2010 |
| Patent application number | Description | Published |
| 20080205888 | Semiconductor optical amplifier type gate switch drive circuit, semiconductor optical amplifier type gate switching drive, and optical cross connect - A drive circuit is provided for a semiconductor optical amplifier type gate switch includes a first transmission path and a second transmission path. The first transmission path includes a common first sub-path between a signal source and a first node; and an individual second sub-path for each of a plurality of operational amplifiers between the first node and a corresponding one of the operational amplifiers. The second transmission path includes an individual third sub-path between each of the operational amplifiers and a second node; and a common fourth sub-path between the second node and the semiconductor optical amplifier type gate switches. Transmission delay times of all the individual second sub-paths are equal, and transmission delay times of all the individual third sub-paths are equal. | 08-28-2008 |
| 20080239472 | Semiconductor optical amplification module, optical matrix switching device, and drive circuit - A semiconductor optical amplification module that can suppress ringing without increasing power consumption or circuit size or inhibiting high-speed operation. A semiconductor optical amplifier outputs an optical signal inputted according to driving current outputted from a drive circuit. A diode is connected in parallel with the semiconductor optical amplifier. As a result, it becomes possible to suppress ringing without connecting a large resistor to the drive circuit. | 10-02-2008 |
| 20090058534 | Non-inverting amplifier circuit and optical switch driver circuit - A non-inverting amplifier circuit is disclosed that includes an operational amplifier and a preemphasis circuit connected between the operational amplifier and a signal source. The preemphasis circuit is configured to compensate for the internal delay of a load connected to the output of the operational amplifier by emphasizing a high-frequency component of a signal fed from the signal source. | 03-05-2009 |
| 20090237127 | OPTICAL-SWITCH DRIVE CIRCUIT AND METHOD THEREOF - An optical-switch drive circuit including a driver unit that generates, in response to a control signal, an on/off signal for driving a semiconductor optical amplifier gate switch, and a buffer unit having a high input impedance and connected between an output terminal outputting the on/off signal and the semiconductor optical amplifier gate switch. In the optical-switch drive circuit the buffer unit may include a high-resistance voltage divider that is connected with the output terminal, and an operational amplifier that buffers, and provides to the semiconductor optical amplifier gate switch, a divided voltage of the voltage divider. | 09-24-2009 |
| 20090297147 | Drive circuit and optical switch - A drive circuit includes a first transistor that is controlled to be in on or off state in response to a control signal, and outputs, in on state, a positive current which is input from a first operational amplifier connected with a drain of the first transistor to a semiconductor optical amplifier; and a second transistor that is connected with a source of the first transistor, and is in inverse on or off state to the state of the first transistor. The drive circuit also includes a negative voltage circuit that is connected to a source of the second transistor, and outputs, when the second transistor is in on state, a negative current to the semiconductor optical amplifier. | 12-03-2009 |
| 20110050293 | Driving circuit of optical gate switch - A driving circuit of a semiconductor optical amplifier type gate switch constituting a matrix optical switch is provided with an operation amplifier into which a driving signal is input and from which a current corresponding to the driving signal is output, an inductance element provided at an output terminal of the operation amplifier, and a circuit composed of a diode element and a resistor element connected in parallel and provided between the inductance element and the semiconductor optical amplifier. | 03-03-2011 |