A multi-party system, devices, and method for token-based obfuscation of secret information. A first party device may store a secret original program T and original data D, retrieve a set of secret keys SK, obfuscate the original program T with the set of secret keys SK to generate an obfuscated program T, obfuscate the original data D with the set of secret keys SK to generate a token of the data Token(D), and transfer the obfuscated program T and Token(D) to a second party device. The second party device may evaluate the obfuscated program T on the token of the data Token(D) to generate a result equivalent to evaluating the original program T on the original data D if the same set of secret keys SK is used to obfuscate the original program T and the original data D, without exposing the original program T to the second party.

A computer-implemented method includes: encrypting, by a first data party, identification data to generate a first identification data ciphertext, in which the first data party holds an identification dataset including the identification data; sending a first ciphertext set to a second data party, in which the first ciphertext set includes the first identification data ciphertext; receiving a second ciphertext set from the second data party; decrypting the second identification data ciphertext to generate a third identification data ciphertext, in which a third ciphertext set includes the third identification data ciphertext; receiving a fourth ciphertext set from the second data party, obtaining the third identification data ciphertext common to the third ciphertext set and the fourth ciphertext set; calculating a homomorphic addition result of the business data ciphertext corresponding to the third identification data ciphertext; and sending the homomorphic addition result to the second data party.

A method for performing secure computations on records, comprising: receiving a request to apply an arithmetic computation on a record; assigning a respective partial record to each of a plurality of computational processes; instructing each of the computational processes sharing a computation scheme to perform the following: submitting the arithmetic computation to the computation scheme to assemble a processed partial record from the respective partial record components; instructing each of the plurality of computational processes to verify an integrity of at least one of the plurality of processed partial records by: broadcasting combined encryptions of one of the plurality of processed partial record components to all other of the plurality of computational processes and analyzing received combined encryptions to detect integrity in the other of the processed partial record components; and when the detected integrity is valid, calculating a response to the request by combining the received processed partial records.

Described is a system for anonymous job allocation and majority voting in a cloud computing environment. The system broadcasts a job to physical nodes, each of the physical nodes having a control operations plane (COP) node and one or more service nodes associated with the COP node. A set of redundant job assignments is distributed to individual COP nodes pursuant to a private job assignment schedule, such that each individual COP node is only aware of its own assignment and corresponding job. The service nodes execute the job assigned to the COP nodes such that the service nodes each complete a task associated with the job and forward an individual result to their associated COP node. A privacy-preserving result checking protocol is performed amongst the COP nodes such that secret shares of a majority result are obtained and the majority result is provided to a client.

The subject matter discloses a computerized system for securing data, comprising a first node, comprising a first memory storage configured to store a first share of a cryptographic key and a communication module, a second node, in communication with the first node, comprising a second memory storage configured to store a second share of the cryptographic key, wherein the first share and the second share of the cryptographic key are required to perform a cryptographic operation using a multi-party computation (MPC) process, wherein the second node further comprises a control unit configured to change an operation mode of the second share from enable to disable, wherein the disable operation mode prevents performing the cryptographic operation using the MPC process.

Methods and systems for consensus-based online authentication are provided. An encryption device may be authenticated based on an authentication cryptogram generated by the encryption device. The encryption device may transmit a request for security assessment to one or more support devices. The support devices may individually assess the encryption device, other security devices, and contextual information. The support devices may choose to participate in a multi-party computation with the encryption device based on the security assessments. Support devices that choose to participate may transmit one or more secret shares or partial computations to the encryption device. The encryption device may use the secret shares or partial computations to generate an authentication cryptogram. The authentication cryptogram may be transmitted to a decryption device, which may decrypt the authentication cryptogram, evaluate its contents, and authenticate the encryption device based on its contents.

A data comparison device holds first and second encrypted data of first and second plaintext, respectively. The first plaintext is divided into a plurality of blocks and the first encrypted data is generated by executing encryption of each of the plurality of blocks and shuffling of the plurality of blocks. The second plaintext is divided into a plurality of blocks and the second encrypted data is generated by executing encryption of each of the plurality of blocks. In at least one of the first encrypted data and the second encrypted data, a plaintext value is embedded as a value indicating a magnitude comparison result, and the data comparison device compares blocks at the same position before shuffling of the first encrypted data and the second encrypted data based on the embedded value and determines a magnitude relationship between the first plaintext and the second plaintext.

This disclosure relates to secret sharing data exchange for generating a data processing model. In some aspects, first data party device determines respective values of first coefficients based on a first share of service data. The first coefficients are corresponding coefficients of respective target variables in different terms of a polynomial expression and the target variables are variables that are in the polynomial expression and associated with the first share of the service data. A second data party device determines respective values of second coefficients based on a second share of the service data. The second coefficients include coefficients other than the first coefficients in the different terms of the polynomial expression. The first data party device secretly shares respective values of the different terms in the polynomial expression in parallel based on the respective values of the first coefficients.

A method and system for performing a calculation of a privacy preserving scalar product are provided. A first party and a second party (e.g., a first computer and a second computer) possessing a first vector and a second vector respectively, can concurrently determine the scalar product of the two vectors, without revealing either vector to the other party. Each vector can be masked and then encrypted using a public key of an asymmetric key pair. Using homomorphic encryption operations, the scalar product of the vectors can be determined while the vectors are still encrypted. Each party can compare the scalar product, or a value derived from the scalar product against a predetermined threshold. As an example, two parties can perform the scalar product to compare two biometric templates expressed as vectors without revealing the biometric templates to one another, preserving the privacy of persons corresponding to those biometrics.

Some embodiments are directed to a computation device configured for batch-wise multiparty verification of a computation which has been performed multiple times. The computations being multiparty computations that are cryptographically shared between the computation device and multiple other computation devices. The computation device is configured to perform the computation a further time to obtain a randomizing computation on a randomizing set of values.