A device, system and method for privacy enhanced proximity detection by secure collaboration between a first party without access to user locations and a second party without access to a target user identifier. The second party may receive from the first party a homomorphic encryption public key and homomorphic encrypted target user identifier or masked target location, and may determine an associated homomorphic encrypted target user location. The second party may search a homomorphically encrypt database of user locations and associated user identifiers for homomorphic encrypted proximate user identifiers associated with homomorphic encrypted user locations proximate to the homomorphic encrypted target user location. The second party may send the first user the search result of homomorphic encrypted proximate user identifiers to be decrypted by the first party with a private key to identify proximate user identifiers without knowing their locations.

Systems and methods for generating min-increment counting bloom filters to determine count and frequency of device identifiers and attributes in a networking environment are disclosed. The system can maintain a set of data records including device identifiers and attributes associated with device in a network. The system can generate a vector comprising coordinates corresponding to counter registers. The system can identify hash functions to update a counting bloom filter. The system can hash the data records to extract index values pointing to a set of counter registers. The system can increment the positions in the min-increment counting bloom filter corresponding to the minimum values of the counter registers. The system can obtain an aggregated public key comprising a public key. The system can encrypt the counter registers using the aggregated shared key to generate an encrypted vector. The system can transmit the encrypted vector to a networked worker computing device.

The invention proposes a method for processing personal data, having the steps of (a) Functional encryption of candidate personal data using a functional encryption public key, (b) For at least one reference personal data, functional decryption of the encrypted candidate biometric data using a functional decryption private key for the polynomial function of degree 1 or 2 parameterized with said reference personal data.

Methods, systems, and apparatus, including a method for determining network measurements. In some aspects, a method includes receiving, by a first aggregation server and from each of multiple client devices, encrypted impression data. A second aggregation server received from each of at least a portion of the multiple client devices, conversion data that includes, for each conversion recorded by the client device, encrypted conversion value data. The first aggregation server and the second aggregation server perform a multi-party computation process to decrypt the encrypted impression data and the encrypted conversion data.

Methods, systems, and apparatus, including a method for determining network measurements. In some aspects, a method includes receiving, by a first aggregation server and from each of multiple client devices, encrypted impression data. A second aggregation server receives, from each of at least a portion of the multiple client devices, encrypted conversion data. The first aggregation server and the second aggregation server perform a multi-party computation process to decrypt the encrypted impression data and the encrypted conversion data. Each portion of decrypted impression data and each portion of decrypted conversion data is sent to a respective reporting system.

Privacy-preserving homomorphic inferencing utilizes batch processing on encrypted data records. Each data record has a private data portion of interest against which the inferencing is carried out. Batch processing is enabled with respect to a set of encrypted data records by techniques that ensure that each encrypted data record has its associated private data portion in a unique location relative to the other data records. The set of encrypted data records are then summed to generate a single encrypted data record against which the inferencing is done. In a first embodiment, the private data portions of interest are selectively and uniquely positioned at runtime (when the inferencing is being applied). In a second embodiment, the private data portions of interest are initially positioned with the data-at-rest, preferably in an off-line process; thereafter, at runtime individual encrypted data records are processed as necessary to adjust the private data portions to unique positions prior to batching.

Systems and methods for cryptography based on 128 bit integers include: receiving a complex input, the input including a 128-bit number; encrypting by: setting an imaginary part of the input to a predetermined value; encrypting the input using a Fourier transform and a scaling factor; adding a first noise and a second noise to the encrypted input, wherein the second noise obfuscates the first noise; and decrypting by: receiving the encrypted input with added first noise and second noise; estimating a standard deviation of the first noise based on an imaginary part of the received encrypted complex input; computing a standard deviation of the second noise based on the standard deviation of the first noise and a predetermined parameter; and decrypting the encrypted message using an inverse Fourier transform, the first noise, and the second noise.

Disclosed is a method and apparatus for modulus refresh, where the method for modulus refresh of a ciphertext in homomorphic encryption includes receiving a first ciphertext corresponding to a first modulus, generating a second ciphertext by performing a blind rotation on the first ciphertext, and generating a target ciphertext corresponding to a second modulus greater than the first modulus based on the first ciphertext and the second ciphertext.

Systems, methods, and computer products for administering the association of a network identifier with a blockchain address for a blockchain enable operations that may include obtaining, by an authoritative record entity, an initiation of an administrative action regarding an association of the network identifier with the blockchain address, wherein the administrative action comprises at least one of deleting the association, updating the association, modifying the association, or renewing the association; and providing, in response to the obtaining, a registration entity proof message, wherein the registration entity proof message comprises a signature by a private key of the authoritative record entity, wherein the registration entity proof message specifies a registration entity of record for the network identifier. An executable program stored on the blockchain may be configured to obtain the signature, verify the signature, and implement the administrative action regarding the association of the network identifier with the blockchain address.

A method for conversion of digital assets to fiat currency using a secondary blockchain and mirrored accounting includes: receiving transaction data corresponding to a first blockchain transaction processed using a first blockchain, the transaction data including a payer identifier, recipient identifier, and blockchain currency amount; validating an entity as an authorized entity associated with the payer identifier; determining a fiat currency amount based on the blockchain currency amount; generating a second blockchain transaction, the second blockchain transaction including an unspent transaction output, destination address associated with the authorized entity, and the blockchain currency amount and/or the fiat currency amount; confirming addition of the second blockchain transaction to a second blockchain; and initiating a transfer for the fiat currency amount from a first transaction account to a second transaction account, the second transaction account being associated with the authorized entity.