BPDS: A Blockchain based Privacy-Preserving Data Sharing for Electronic Medical Records
This addresses privacy and fragmentation issues in healthcare data sharing for patients and hospitals, but it is incremental as it combines existing blockchain and cryptographic techniques.
The authors tackled the problem of fragmented and privacy-risky electronic medical records (EMRs) by proposing BPDS, a blockchain-based system that securely stores EMRs in the cloud with tamper-proof indexes on a consortium blockchain, enabling automated sharing via smart contracts and strong privacy through CP-ABE and content extraction signatures, resulting in greatly reduced data leakage risks and secure, effective data sharing.
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.