A method includes: determining, by a computing device communicably coupled to a blockchain network, participants in a remittance transaction, in which each participant has a corresponding account in a blockchain ledger of the blockchain network, and in which each account includes one or more assets; assembling the remittance transaction based on one or more to-be-spent assets of the one or more assets in an account corresponding to a real remitter, one or more covered assets of the one or more assets in an account corresponding to a fake remitter, and one or more encrypted transfer amounts; generating a linkable ring signature for the remittance transaction based on a private key held by the real remitter, a public key held by the real remitter, and a public key held by the fake remitter; and submitting the remittance transaction and the linkable ring signature to the blockchain network for completion.

Described in detail herein is a method for encrypting or encoding time-stamped location data associated with a computing device. The method converts time and location information associated with the computing device into a vector format. The method generates a code vector based on the converted time and location vector. The method sorts entries in the code vector based at least in part on a predetermined ordering scheme. The method executes a random modification to each of the sorted entries. The method compares the code vector to at least one other code vector associated with another computing device. The method identifies other code vectors within a specified distance of the given code vector. The method concludes that the computing device and the at least one other computing device were in proximity to each other during a time period corresponding to the time information.

Some embodiments enable distributing data (e.g., recorded video, photographs, recorded audio, etc.) to a plurality of users in a manner which preserves the privacy of the respective users. Some embodiments leverage homomorphic encryption and proxy re-encryption techniques to manipulate the respective data so that selected portions of it are revealed according to an identity of the user currently accessing the respective data.

Disclosed is a mechanism for performing an anonymous transfer using a blockchain. A sender's device generates a commitment based on a serial number of a zero-knowledge token and a value of the zero-knowledge token. Moreover, the sender's device generates a range proof and a balance proof for the commitment. The range proof verifies that the value of the zero-knowledge token is within a preset range. The balance proof verifies that the value of a set of input tokens is greater than or equal to the value of the zero-knowledge token. The sender's device sends a conversion request to the blockchain network. The conversion request consumes the set of input tokens and generates the zero-knowledge token. The conversion request includes the generated commitment, the generated range proof, and the generated balance proof.

A plurality of anonymized publisher-user identifiers are received at a processor, and a plurality of anonymized advertiser-user identifiers are received from an advertiser at the processor. Without de-anonymizing any publisher-user identifiers in the received plurality of publisher-user identifiers and any advertiser-user identifiers in the received plurality of advertiser-user identifiers, the processor obliviously computes an intersection among the received publisher-user identifiers and the received ad-user identifiers to create an intersection set containing a plurality of advertiser-user identifiers matched with publisher-user identifiers.

A method for operating an attribute assertion device having a processor and memory to create an unlinkable digital signature-equivalent of an assertion message that is verifiable—by a service provider receiving the unlinkable digital signature-equivalent—as being generated from a digital signature of a known attribute provider having a public key PK.sub.AP. Operating the processor of the attribute assertion device to transform a digital signature of the attribute message into an unlinkable digital signature-equivalent using a one-way transformation of the signature, with the transformation process using a random value generated by the attribute assertion device and a challenge provided by the service provider.

The present disclosure is generally directed to systems and methods for providing privacy to a user of a user device that is used for interacting with a networked software platform. A server computer coupled to the user device receives a hashed device ID of the device and generates a unique user ID in the form of a unique number. The user ID can be used by the server and other entities to gather information related to the activities of the user with respect to the networked software platform, which can be, for example, a video game platform, a social media platform, or a health-related diagnostic tool. The identity of the user remains anonymous during the information gathering procedures because neither the device ID nor the identity of the user is transmitted over the network when the user is participating in activities of the networked software platform.

Described herein are systems and methods for a providing Ledger as a Service (LaaS). Blockchain technology helps bring potential solutions to the distributed ledger problem, with a linear record structure to record transaction history. However, there are different types of blockchain techniques (e.g., Hyperledger, Ethereum, Quorum), and users/developers need to know the explicit features of each technique and align with the required APIs. Ledger as a Service can allow users to an develop applications more efficiently, and can allow users to easily migrate applications among different blockchain techniques and platforms (e.g., between Hyperledger and Ethereum). LaaS can also allow for simplified transactions with a blockchain, and can additionally provide simplified communication between blockchains of different types.

A data broker platform may store one or more data sharing preference settings of a subscriber for the subscriber data of the subscriber in a corresponding subscriber preference record of a subscriber preference blockchain ledger. The platform may further store one more access policy settings with respect to the subscriber data in a corresponding access configuration record of an access configuration blockchain ledger. The platform may receive a data request from a computing device of a third-party entity to access a set of subscriber data of the subscriber. Accordingly, the platform may provide the computing device of the third-party entity with access to the set of subscriber data when the platform determines using records in the subscriber preference blockchain ledger and the access configuration blockchain ledger that the third-party entity is permitted to access the set of subscriber data.

A real-time event processing system receives event data containing telemetric data and one or more personal identifiers. The personal identifier in the event data is replaced with an obfuscated value so that the telemetric data may be used without reference to the personal identifier. A reversible map is used to reverse the obfuscated personal identifier to its original value. In the case when a request is received to delete the mapped personal identifier, the link to the entry in the reversible map is broken by associating the personal identifier with a different obfuscated value.