Blockchain-based medical data sharing schedule guaranteeing security of individual entities

In a modern electronic medical system, data sharing between medical institutions must have a more comprehensive understanding of the patient's condition. However, different hospitals typically use other databases, even if the data belong to the same person. Each hospital manages its database in a centralized and closed manner. This approach makes the databases vulnerable to single-point attacks by malicious attackers and undermines medical care continuity. In this paper, we use a blockchain concept that provides a secure distributed environment to avoid single-point attacks. We develop a novel medical data sharing schedule that uses the blockchain to integrate each hospital's resources. Compared with other blockchain-based schemes, we categorize and manage different requests for medical data sharing: (i) sharing between hospitals of the same level; (ii) sharing between hospitals of different levels. Additionally, our schedule ensures the security of individual entities in the process of data sharing. We conduct a security analysis and a comparative validation to show that the proposed systems are secure. In the subsequent analysis of the system, the feasibility of the proposed system was examined.