Patent application number | Description | Published |
20090086962 | ENCRYPTION OPERATING APPARATUS - Valid code data and invalid code data are alternately input to a register that fetches data synchronously with a clock signal. A state of a data value input to the register is monitored. Each time when it is determined that the data is stabilized by the valid code data, the register holds the valid code data. | 04-02-2009 |
20110131470 | MEMORY CHIP - According to one embodiment, a memory chip, which is connected to a controller that controls reading and writing of data in response to a request from an external device, includes: a memory including a special area that is a predetermined data storage area; a key storage unit that stores therein a second key that corresponds to a first key used by the external device to convert the data; a converting unit that receives, from the controller, data to be written into the special area and generates converted data by converting the data to be written using the second key; and a writing unit that writes the converted data into the special area. | 06-02-2011 |
20110246791 | MEMORY CHIP, INFORMATION STORING SYSTEM, AND READING DEVICE - According to one embodiment, a memory chip, which is connected to a writing device that writes data and to a reading device that reads data, includes: a memory including a first area that is a predetermined data storage area; a second encryption key generating unit that receives second key information stored in the reading device and generates a third key; and a sending unit that transmits, to the reading device, second encrypted data obtained by encrypting data stored in the memory using the third key. The second encrypted data is received by the reading device and is decrypted by using a fourth key that is stored in the reading device and that corresponds to the third key. | 10-06-2011 |
20110311048 | CRYPTOGRAPHIC OPERATION APPARATUS, STORAGE APPARATUS, AND CRYPTOGRAPHIC OPERATION METHOD - According to one embodiment, the cryptographic operation apparatus performs a cryptographic operation using first and second key data and includes an initial mask value creating unit that creates the initial mask value using the second key data and data information. In addition, the cryptographic operation apparatus further includes a mask value updating unit that creates the mask value using the initial mask value and a mask value storing unit that stores and outputs the initial mask value and the created mask value. In addition, the encryption is performed using the input data, the first key data, and the output mask value. | 12-22-2011 |
20120069993 | CRYPTOGRAPHIC APPARATUS AND MEMORY SYSTEM - According to one embodiment, a cryptographic apparatus includes: cryptographic cores (“cores”), an assigning unit, a concatenating unit, and an output controlling unit. If a CTS flag thereof is on, each core encrypts using a symmetric key cipher algorithm utilizing CTS, while using a symmetric key. When an input of a CTS signal is received, the assigning unit assigns first input data to a predetermined core and turns on the CTS flag thereof. The concatenating unit generates concatenated data by concatenating operation data generated during encrypting the first input data, with second input data that is input immediately thereafter. The output controlling unit controls outputting the concatenated data to the predetermined core, outputting first encrypted data obtained by encrypting the concatenated data, and over outputting second encrypted data obtained by encrypting the first input data, and further turns off the predetermined core's CTS flag. | 03-22-2012 |
20120131078 | ARITHMETIC DEVICE - According to one embodiment, a first shift amount calculation unit counts the number of continuous zeros from a less significant bit toward a more significant bit of an intermediate result of a computation of Montgomery multiplication result z and calculates a first shift amount. A second shift amount calculation unit counts the number of continuous zeros from a less significant bit toward a more significant bit of redundant-binary-represented integer x and calculates a second shift amount. An addition/subtraction unit calculates the intermediate result by adding/subtracting, with respect to the intermediate result which has been bit-shifted by the first shift amount, the integer p, and the integer y which has been bit-shifted by the second shift amount. An output unit outputs, as the Montgomery multiplication result z, the intermediate result when the sum of the first shift amounts is equal to the number of bits of the integer p. | 05-24-2012 |
20120230492 | ENCRYPTION DEVICE - According to an embodiment, an encryption device includes a symmetric-key operation unit; a division unit; an exclusive OR operation unit; a multiplication unit that performs multiplication on a Galois field; and a control unit that controls the above units. When the input data is divided into blocks, with the predetermined length, and the first mode of operation is designated on a (j−1)-th block, the control unit performs control such that the multiplication unit performs multiplication with a predetermined value based on the (j−1)-th block, performs control such that the exclusive OR operation unit sums a multiplication result and data of a j-th block, and performs control such that the exclusive OR operation unit sums an operation result of the exclusive OR operation unit and an operation result of the multiplication unit on the (j−1)-th block. | 09-13-2012 |
20120237035 | KEY SCHEDULING DEVICE AND KEY SCHEDULING METHOD - According to one embodiment, in a key scheduling device, a non-linear transformation unit non-linearly transforms at least one of partial keys resulting from dividing an expanded key. A first linear transformation unit includes first and second circuits. The second circuit linearly transforms the partial key by directly using a transformation result from the non-linear transformation unit. A first storage stores the partial key linearly transformed by the first linear transformation unit. A second linear transformation unit linearly transforms, inversely to the first linear transformation unit, each of partial keys other than the partial key linearly transformed by the second circuit out of the partial keys stored in the first storage, and outputs inversely transformed partial keys. A second storage stores one of inputs to the second circuit. An outputting unit connects the respective inversely transformed partial keys and the input stored in the second storage to be output as a second key. | 09-20-2012 |
20120246356 | CONTROL DEVICE AND COMPUTER PROGRAM PRODUCT - According to an embodiment, a control device includes a receiving unit configured to receive an interrupt request requesting an interrupt process to be executed by a processing device that executes one or more processes; a storage unit configured to store therein the interrupt request; a determining unit configured to determine a state of the processing device; a sending unit configured to send the interrupt request to the processing device; and a control unit configured to store the interrupt request received by the receiving unit in the storage unit when the processing device is determined by the determining unit to be in an idle state in which the processing device is not executing the processes and a predetermined condition is not satisfied, and to control the sending unit to send the interrupt request stored in the storage unit to the processing device when the predetermined condition is satisfied. | 09-27-2012 |
20120246390 | INFORMATION PROCESSING APPARATUS, PROGRAM PRODUCT, AND DATA WRITING METHOD - According to one embodiment, an information processing apparatus includes an auxiliary storage unit, a non-volatile main storage unit, a secondary cell, a first writing unit, and a second writing unit. The non-volatile main storage unit includes a cache area to temporarily store therein data that is to be stored in the auxiliary storage unit. The first writing unit writes the data into the cache area. The second writing unit writes the data written in the cache area into the auxiliary storage unit when an amount of power in the secondary cell is greater than a predetermined first threshold. | 09-27-2012 |
20120246501 | CONTROLLER AND PROGRAM PRODUCT - According to one embodiment, a controller includes a state detecting unit, a calculating unit, and a determining unit. The state detecting unit detects an idle state in which indicates there are no process that can execute on a processing device capable of performing one or more processes. The calculating unit calculates a resuming time, which indicates a time length until the next process starts, when the state detecting unit detects the idle state. The determining unit determines an operation mode of the processing device on the basis of the resuming time calculated by the calculating unit. | 09-27-2012 |
20120246503 | INFORMATION PROCESSING APPARATUS AND JUDGING METHOD - According to one embodiment, an information processing apparatus includes a processor, a non-volatile storage unit, a receiving unit, a judging unit, and a transmitting unit. The receiving unit receives from the processor an inquiry about accessibility of the storage unit. The judging unit judges, upon receipt of the inquiry, whether the storage unit is accessible on the basis of a start-up time period between starting power supply to the storage unit and activation of the storage unit. The transmitting unit transmits a judgment result obtained by the judging unit to the processor. | 09-27-2012 |
20120307997 | ENCRYPTION DEVICE - According to an embodiment, an encryption device performs encryption processing using an encryption key and calculates encrypted data from plain data. The encryption device includes: a register; an input unit configured to receive plain data; a first partial encryption unit configured to calculate first intermediate data from the plain data; a second partial encryption unit configured to calculate (i+1)-th intermediate data based on i-th intermediate data and the encryption key; a first transform unit configured to: transform j-th intermediate data into j-th transformed data; and store the j-th transformed data in the register; and a second transform unit configured to transform the j-th transformed data into the j-th intermediate data; a third partial encryption unit configured to calculate encrypted data from the N-th intermediate data. The second partial encryption unit is configured to repeat processing to calculate (j+1)-th intermediate data while j is equal to from 1 to N−1. | 12-06-2012 |
20130073812 | CACHE MEMORY DEVICE, PROCESSOR, AND INFORMATION PROCESSING APPARATUS - According to an embodiment, a cache memory device caches data stored in or data to be stored in a memory device. The cache memory device includes a memory area that includes a plurality of cache lines; and a controller. When the number of dirty lines among the cache lines exceeds a predetermined number, the controller writes data of the dirty lines into the memory device, each of the dirty lines containing data that is not written in the memory device. | 03-21-2013 |
20130080812 | CONTROL SYSTEM, CONTROL METHOD, AND COMPUTER PROGRAM PRODUCT - According to an embodiment, a control system includes a processing device; a main storage device to store the data; a cache memory to store part of the data stored; a prefetch unit to predict data highly likely to be accessed and execute prefetch, reading out data in advance onto the cache memory; and a power supply unit. The system further includes: a detecting unit to detect whether the processing device is in an idle state; a determining unit that determines whether to stop the supply of power to the cache memory in accordance with the state of the prefetch when determined as idle state; and a power supply control unit that controls the power supply unit so as to stop the supply of power, or controls the power supply unit so as to continue the supply of power. | 03-28-2013 |
20130191670 | CONTROL DEVICE, SYSTEM, AND COMPUTER PROGRAM PRODUCT - According to an embodiment, a control device includes a calculator and a setting unit. The calculator is configured to calculate a system processing time indicating a time required for processing executed after a system, the system including a plurality of elements, power to each element being individually controlled, resumes from a sleep state in which the number of elements supplied with power is limited to a predetermined number and an operation of the system is stopped. The setting unit is configured to set a mode indicating an operation state of the system according to the system processing time calculated by the calculator when a resume factor indicating a factor for resuming the system from the sleep state occurs. | 07-25-2013 |
20130254773 | CONTROL APPARATUS, CONTROL METHOD, COMPUTER PROGRAM PRODUCT, AND SEMICONDUCTOR DEVICE - According to an embodiment, a control apparatus for controlling a target device includes an estimation unit and an issuing unit. The estimation unit is configured to estimate a second amount of energy required for the entire system including the target device and the control apparatus until the target device completes an execution of its function that is requested in accordance with an execution request for the target device. The issuing unit is configured to issue a control command for causing the target device to execute its function in accordance with the execution request, when the first amount of energy at a time point of receiving the execution request is greater than the second amount of energy. | 09-26-2013 |
20130268781 | STATE CONTROL DEVICE, INFORMATION PROCESSING DEVICE, COMPUTER PROGRAM PRODUCT, AND SEMICONDUCTOR DEVICE - According to an embodiment, a state control device controls a state transition of an information processing device. The information processing device includes a processor; a power supply unit; and an electric storage unit. The state control device includes a controller to, when the power amount accumulated in the electric storage unit is decreased to a first power amount while the information processing device is in a first state, cause the information processing device to transit from the first state to a second state in which power consumption of the processor is lower than that in the first state, and to, when the power amount accumulated in the electric storage unit is increased to a second power amount larger than the first power amount while the information processing device is in the second state, cause the information processing device to transit from the second state to the first state. | 10-10-2013 |
20130290738 | MEMORY CHIP - According to one embodiment, a memory chip, which is connected to a controller that controls reading and writing of data in response to a request from an external device, includes: a memory including a special area that is a predetermined data storage area; a key storage unit that stores therein a second key that corresponds to a first key used by the external device to convert the data; a converting unit that receives, from the controller, data to be written into the special area and generates converted data by converting the data to be written using the second key; and a writing unit that writes the converted data into the special area. | 10-31-2013 |
20140013138 | MEMORY CONTROL DEVICE, SEMICONDUCTOR DEVICE, AND SYSTEM BOARD - According to an embodiment, a memory control device controls a memory from/to which data are read/written by a processor. The memory control device includes a clock switcher and a control signal switcher. The clock receives as input a first clock and a second clock at a higher frequency than the first clock, supplies the first clock to the memory until the second clock becomes stable, and supplies the second clock after the second clock has become stable. The a control signal switcher starts supplying, to the memory, a first control signal for initializing the memory to a state allowing reading/writing of data by the processor while the first clock is being supplied to the memory, and supplies, to the memory, a second control signal according to the reading/writing of data by the processor, after the second clock is supplied to the memory and the memory is initialized. | 01-09-2014 |
20140013140 | INFORMATION PROCESSING APPARATUS AND COMPUTER PROGRAM PRODUCT - According to an embodiment, an information processing apparatus includes a processor, a first memory, and a power supply controller. The processor is configured to execute a program. The first memory is configured to store therein the program. The power supply controller is configured to stop supplying a power to the first memory when the processor transitions to an idle state where the processor waits for an interrupt, and start supplying the power to the first memory when the processor receives the interrupt in the idle state. When the processor receives the interrupt in the idle state, the processor executes initialization of the first memory to set the first memory into a state where the first memory is accessible from the processor. | 01-09-2014 |
20140064483 | COMPUTER PROGRAM PRODUCT AND METHOD FOR PROCESSING INFORMATION TO OBTAIN AN HMAC - One embodiment is a computer program product for processing information to obtain an HMAC, comprising: by using a padding circuit, generating first key data by adding 0 with respect to secret key data, setting the secret key data as second key data, or generating third key data by adding 0 with respect to a first digest value, according to comparison result of a second key length and a block length of the hash function, and performing an exclusive OR operation with a second constant with respect to one of the first key data, the second key data, and the third key data to calculate first data; by using a hash calculation circuit, obtaining the first digest value, and obtaining a second digest value, by using a holding circuit, storing the secret key data or the first digest value; and by using a control unit, managing a processing state for calculating the HMAC. | 03-06-2014 |
20140089715 | INFORMATION PROCESSING APPARATUS, INFORMATION PROCESSING METHOD, AND COMPUTER PROGRAM PRODUCT - According to an embodiment, an information processing apparatus is powered by a power source including a power generation unit and a power storage device that stores power generated by the power generation unit. The information processing apparatus includes a first obtaining, a second obtaining unit, and a first control unit. The first obtaining unit is configured to obtain first information indicating a value of power generated by the power generation unit. The second obtaining unit is configured to obtain second information indicating an value of stored energy in the power storage device. The first control unit is configured to start a process that is set in advance when the value of power indicated by the first information is greater than zero and the value of stored energy indicated by the second information is equal to or greater than a first threshold value. | 03-27-2014 |
20140245045 | CONTROL DEVICE AND COMPUTER PROGRAM PRODUCT - According to an embodiment, a control device includes a processor setting unit, a resumption data reading unit, and a resumption processing unit. The processor setting unit is configured to identify, among a plurality of processors included in an information processing system, each of which is connected to one or more memories, a processor connected to a memory storing resumption data for resuming the information processing system and to activate the identified processor, in response to a resumption request for resuming the information processing system from hibernation. The information processing system includes two or more processors each connected with one or more memories. The resumption data reading unit is configured to read the resumption data from the memory that stores the resumption data. The resumption processing unit is configured to resume the information processing system by using the read resumption data. | 08-28-2014 |
20140245047 | INFORMATION PROCESSING APPARATUS, OPERATION STATE CONTROL METHOD, AND COMPUTER PROGRAM PRODUCT - According to an embodiment, an information processing apparatus that includes a processor, has a first control unit, a power storage unit, and a second control unit. The first control unit is configured to control execution of a process by the processor. The power storage unit is configured to store therein power. The second control unit is configured to control reduction of power consumption of the information processing apparatus in a case where there is a process waiting to be executed and an amount of stored power of the power storage unit is equal to or less than a first threshold. | 08-28-2014 |
20140298043 | MEMORY CHIP - According to one embodiment, a memory chip, which is connected to a controller that controls reading and writing of data in response to a request from an external device, includes: a memory including a special area that is a predetermined data storage area; a key storage unit that stores therein a second key that corresponds to a first key used by the external device to convert the data; a converting unit that receives, from the controller, data to be written into the special area and generates converted data by converting the data to be written using the second key; and a writing unit that writes the converted data into the special area. | 10-02-2014 |
20150019895 | INFORMATION PROCESSING APPARATUS AND JUDGING METHOD - According to one embodiment, an information processing apparatus includes a processor, a non-volatile storage unit, a receiving unit, a judging unit, and a transmitting unit. The receiving unit receives from the processor an inquiry about accessibility of the storage unit. The judging unit judges, upon receipt of the inquiry, whether the storage unit is accessible on the basis of a start-up time period between starting power supply to the storage unit and activation of the storage unit. The transmitting unit transmits a judgment result obtained by the judging unit to the processor. | 01-15-2015 |