A secure text having an authentication code is efficiently created. A key generation part 12 generates secure texts ([x], [α], [β]) of “x”, “α” and “β” that are values satisfying xα=β. A secure text generation part 13 generates secure texts [a.sub.i] of random values “a.sub.i” for i=1, . . . , N. An authentication code generation part 14 generates authentication codes [γ(a.sub.i)] by multiplying the secure texts [a.sub.i] by the secure text [α] for i=1, . . . , N. A verification value generation part 15 generates a secure text [w] of a verification value “w” using the secure texts ([x], [α], [β]), the secure text [a.sub.i] and the authentication code [γ(a.sub.i)]. A verification value determination part 16 determines whether the verification value “w” is equal to zero or not.

A transaction consensus processing method for a blockchain is provided. A target node that initiates a proposition performs compression processing on proposed transaction data based on a compression algorithm, and fragments the compressed transaction data into a number of data fragments based on an erasure code algorithm. The method includes: receiving a data fragment of the transaction data that is sent by the target node in a unicast mode, data fragments sent by the target node to nodes in the unicast mode being different; broadcasting the received data fragment to other nodes, and receiving data fragments of the transaction data that are broadcast by the other nodes; performing data recovery on the received data fragment based on an erasure code reconstruction algorithm, performing decompression processing on the recovered transaction data based on a decompression algorithm to obtain original content of the transaction data, and completing the consensus.

Provided is a pre-calculation device capable of keeping a secret against malicious behaviors of participants while keeping a processing load small. A Beaver triple generation processor generates a secret-shared Beaver triple formed of two secret-shared random numbers and a secret-shared value of a product of the two random numbers. A Beaver triple random inspection processor randomly selects a secret-shared Beaver triple, restores the Beaver triple through communication to and from other pre-calculation devices, and confirms that a product of first two elements is equal to a third element. The Beaver triple position stirring processor randomly replaces Beaver triples that have not been restored, to generate replaced secret-shared Beaver triples.

2017PF01995 61 Abstract Evaluation of events using a function According to an aspect, there is provided a first node for evaluating an event using a function. A corresponding computer-implemented method of operating a first node to 5 evaluate an event using a function is also provided. The function is evaluated by two parties using garbled circuits, with each party garbling a circuit representing the function, and evaluating the circuit garbled by the other party. 10

An information processing device includes: a storage that stores execution reservation information transmitted from a user server, wherein the execution reservation information represents an execution reservation of acceptor servers that execute first tasks that have been encrypted and divided; and a processor that: receives a second task from the user server, encrypts and divides the second task to generate the first tasks, requests the acceptor servers to execute the generated first tasks based on the execution reservation information stored in the storage, receives first execution results from the acceptor servers, decrypts and combines the first execution results to generate a second execution result, and transmits the generated second execution result to the user server.

A share generating device obtains N seeds s.sub.0, . . . , s.sub.N−1, obtains a function value y=g(x, e) ϵ F.sup.m of plaintext x ϵ F.sup.m and a function value e, and obtains information containing a member y.sub.i and N−1 seeds s.sub.d, where d ϵ {0, . . . , N−1} and d≠i, as a share SS.sub.i of the plaintext x in secret sharing and outputs the share SS.sub.i. It is to be noted that the function value y is expressed by members y.sub.0 ϵ F.sup.m(0), . . . , y.sub.N−1 ϵ F.sup.m(N−1), which satisfy m=m(0)+ . . . +m(N−1).

Described are various embodiments of a digital data comparison filter, system and method, and applications therefor. In one embodiment, a digital data comparator system comprises two or more transformation engines each having securely stored in association therewith a common key, a common designated comparator threshold number, and a respective identifier; and a reconstitution engine operable to access partial encryption information from each transformation engine and, only upon relating to identical digital data, process each partial encryption information to successfully release the identical digital data.

A method of applying proof of lottery to select block forgers in a blockchain, comprising performing the following at a certain one of a plurality of computing nodes connected to a blockchain network: (1) transmitting one or more of a plurality of participation transactions submitted by at least some of the plurality of computing nodes for participating in selection process conducted to select forgers from the plurality of computing nodes to forge blocks to be added to the blockchain; (2) determining a respective forger, during each selection process, by applying a selection function to an outcome of a hash function and a plurality of participation transactions extracted from a first subset of blocks preceding the respective block, the hash function is applied to a second subset of blocks preceding the respective block; and (3) forging the respective block in case the certain computing node is selected as the respective forger.

A computer node comprising multiple software modules may receive a cryptographic key from a hardware security module. The computer node may use the cryptographic key to produce two key portions, which are distributed to two software modules. These software modules and an optional additional software module may use the key portions in order to encrypt an initial message. The key portions and their locations in memory are periodically updated in order to provide improved cryptographic security.

System and method for digitally signing messages using multi-party computation.