Security research of blockchain technology in electronic medical records

A blockchain-based Electronic Health Record(EHR) data-sharing scheme was proposed to solve the problems of data sharing difficulties and privacy disclosure. METHODS: This paper designs a blockchain-based electronic health record model based on the characteristics of blockchain antitampering, decentralization, and distributed storage. Utilize blockchain network and distributed database to store encryption-related access control policies to prevent EHR data from being tampered with and leaked. Data security sharing protocol combines Distributed Key Generation (DKG) and reencryption. RESULTS: The protocol used the Delegated Proof of Stake(DPOS) algorithm to select the proxy node, which reencrypted the EHR to share data between a pair of users. Simulation experiments and comparative analysis showed that DPOS efficiency was higher than Proof of Work (POW) and slightly lower than the Practical Byzantine Fault Tolerance(PBFT). CONCLUSIONS: The scheme proposed in this paper is more decentralized and less computationally intensive.