A Secure IoT-Enabled Medical Data Sharing Scheme Using Blockchain-Assisted Private Set Intersection

Advances in Internet-of-Things (IoT) technology are enabling the sharing of electronic health records (EHR) via wireless channels. Because EHRs contain sensitive patient information, it is important to preserve data privacy along with medical data sharing. In this paper, we propose a secure medical data sharing scheme using blockchain-assisted private set intersection (PSI). Our approach ensures access control and data availability by having data users upload encrypted private set intersections to the blockchain. We also proposed a mutual authentication phase between the hospital and data user after calculating private set intersection. We thoroughly analyzed the proposed scheme using informal methods and proved security against semi-honest adversary model, correctness, and session key security using formal methods. We also implemented the proposed scheme in real environments using laptop and Raspberry PI 4 to prove the practicality of the proposed scheme. We compared the proposed mutual authentication scheme with existing methods and show that the proposed scheme is better than existing schemes.