BPDS: A Blockchain based Privacy-Preserving Data Sharing for Electronic Medical Records

TL;DR

This paper introduces BPDS, a blockchain-based system that securely shares electronic medical records by combining cloud storage, tamper-proof blockchain indexes, smart contracts, and privacy-preserving access control mechanisms.

Contribution

The paper presents a novel blockchain framework integrating CP-ABE and content extraction signatures for secure, privacy-preserving EMR data sharing.

Findings

BPDS effectively reduces data leakage risks.

Ensures data integrity through tamper-proof blockchain indexes.

Automates secure data sharing via smart contracts.

Abstract

Electronic medical record (EMR) is a crucial form of healthcare data, currently drawing a lot of attention. Sharing health data is considered to be a critical approach to improve the quality of healthcare service and reduce medical costs. However, EMRs are fragmented across decentralized hospitals, which hinders data sharing and puts patients' privacy at risks. To address these issues, we propose a blockchain based privacy-preserving data sharing for EMRs, called BPDS. In BPDS, the original EMRs are stored securely in the cloud and the indexes are reserved in a tamper-proof consortium blockchain. By this means, the risk of the medical data leakage could be greatly reduced, and at the same time, the indexes in blockchain ensure that the EMRs can not be modified arbitrarily. Secure data sharing can be accomplished automatically according to the predefined access permissions of patients through the smart contracts of blockchain. Besides, the joint-design of the CP-ABE-based access control mechanism and the content extraction signature scheme provides strong privacy preservation in data sharing. Security analysis shows that BPDS is a secure and effective way to realize data sharing for EMRs.