Multi-level Personal Data Verification System in Blockchain Environment

This paper proposes an innovative approach to solving the problem of verification and protection of personal data in blockchain-based systems. A method for ensuring data reliability and integrity has been developed, based on a mathematical model using a complex validation function and a hierarchical structure of verification nodes. The proposed model represents each data element as a tuple of components including data version, digital source signature, timestamp, hash of the previous version, and verification metadata. Reliability is evaluated through an integral indicator that takes into account various aspects of validation. A system of "trusted sources" has been implemented with updating of the trust level and the Proof-of-Authority consensus algorithm. Architecturally, the system is implemented through the creation of a hierarchical structure of verification nodes, where each level is responsible for a specific aspect of data verification. The proposed solution provides a balance between data protection and ease of use.