摘要:
In a computing device that calculates a square of an element in a finite field, a vector representation of the element in the finite field is accepted. The vector representation includes a plurality of elements. The computing device performs a multiplication operation on a base field using the accepted elements, and obtains a multiplication value. The multiplication operation is determined by a condition under which the element in the finite field is placed in an algebraic torus. The computing device performs an addition and subtraction operation using the obtained multiplication value and the accepted elements, and obtains a calculation result of the square of the element. The addition and subtraction operation is determined by the condition. The computing device then outputs the calculation result.
摘要:
An input unit inputs encrypted data that elements of a subgroup and expressed in an affine representation. A transforming unit transforms the inputted encrypted data into projective representation data expressed in a projective representation. A plain data calculating unit subjects the projective representation data to a decrypting process previously defined by a cryptosystem, thereby calculating plain data expressed in the projective representation.
摘要:
According to one embodiment, a representation converting unit converts a set of n elements (h0, h1, . . . , hn−1) (hi: a member of a finite field Fp̂m, 0≦i≦n−1) that is a projective representation of a member g of an n-th degree algebraic torus Tn(Fp̂m) (n: positive integer, p: prime number, m: positive integer) into a limited projected representation expressed by a set of n elements (h′0, h′1, . . . , h′n−1) (h′i: a member of the finite field Fp̂m, 0≦i≦n−1) in which at least one element out of the n elements is a zero element 0 or an identity element 1. An arithmetic unit omits part of Fp̂m operation that is arithmetic operation in the finite field Fp̂m based on a fact that an element in the set of n elements (h′0, h′1, . . . , h′n−1) represented by the limited projective representation is a zero element “0” or an identity element “1” when performing Fp̂mn operation that is arithmetic operation of a finite field Fp̂mn in combination with the Fp̂m operation.
摘要:
According to an aspect of the present invention, there is provided a non-linear data converter including: first to fourth converters that each performs a respective converting process on an input bit string to output respective output bit string; a generator that generates a random number bit string; and a selector that selects any one of the output bit strings from the first to fourth converters based on the random number bit string. Each of the converting processes is equivalent to performing a first mask process, a non-linear conversion predetermined for an encoding or a decoding and a second mask process.
摘要:
According to one embodiment, there is provided a data transmission processing device, including: a identifying portion configured to identify a module having sent out data; a storage portion configured to store a sending-out method definition list defined in accordance with each source module and indicating a processing method for the data, the processing method including a data conversion method or permission/prohibition of communication; a determining portion configured to determine a processing method corresponding to the source module identified by the identifying portion by referring to the sending-out method definition list; a converting portion configured to convert the data when the data conversion method is included in the processing method determined by the determining portion; and a transmission portion configured to send out the data or the converted data when the determining portion concludes that communication is permitted.
摘要:
According to an embodiment, in a power usage calculation system, a data management system connected to electric power meters adding up power usage of electric apparatuses and an energy management system are interconnected through a network. Plural pieces of the first partial information are calculated by using the power usage added up by the electric power meters. The plural pieces of the first partial information are stored in storage servers. Each storage server calculates second partial information by using a plurality of pieces of the first partial information of the power usage added up by the electric power meters and transmits the calculated second partial information to the energy management system. The energy management system receives the second partial information respectively transmitted from the storage servers and calculates a total amount of the power usage added up by the electric power meters by using the received second partial information.
摘要:
According to an embodiment, a server to which a plurality of power meters each measuring an amount of power consumption of an electric appliance is connected, includes a receiving unit, a first storage unit and a calculating unit. The receiving unit receives a calculation result. The calculation result is calculated based on the amount of power consumption measured by each of the plurality of power meters and each of random numbers generated according to a probability distribution by each of the plurality of power meters. The first storage unit stores therein parameters for generating random numbers. The calculating unit calculates an estimation value of a sum or average of the amounts of power consumption using the calculation results and the parameters. The estimation value is used for determining whether to perform power control.
摘要:
According to an embodiment, an encryption key generating apparatus includes a converting unit to convert input data using a physically unclonable function and outputs output data; a memory to store a plurality of pattern data, each of which is a partial data in the output data indicated by one of a plurality of index data; a generating unit to generates an encryption key on the basis of the plural of index data; and a comparing unit to compare the output data with the plural of pattern data to detect plural of locations in the output data at which partial data similar to the plural of pattern data is present. The generating unit reproduces, as the plural of index data, the plural of locations detected by the comparing unit and reproduces the encryption key on the basis of the plural of index data that have been reproduced.
摘要:
According to an aspect of the present invention, there is provided a data transmitting apparatus including an authenticator generating unit and a communicating unit. The authenticator generating unit generates a first authenticator by using a first encryption key and generates a second authenticator including a first to an n-th fragment information items by using a second encryption key. The communicating unit transmits a first packet including the first authenticator and the first fragment information item to a destination device and, after the first packet is transmitted, if a response indicating successful authentication is not received from the destination device within a certain period, sequentially transmits an i-th packet (i is an integer being 2 or more and n or less) including the i-th fragment information item to the destination device.