Practical Medical Files Sharing Scheme Based on Blockchain and Decentralized Attribute-Based Encryption

Medical files can help people prevent diseases, increase cure rates, promote medical development and help solve major public health crises. However, medical files are strongly private. It is an urgent problem needed to be solved that how to share medical files with privacy and data security. The existing models based on the centralized certificate authority is a feasible method, but it is possible to experience a single point failure. Besides there is a mismatch between the models and real-life scenario since they are only suitable for single patient. Therefore, this paper proposes a practical medical file sharing scheme based on blockchain and decentralized attribute-based encryption. The blockchain is used to record application and grant of authorizations. Smart contracts provide an interactive platform for all users in the system. By utilizing decentralized attribute-based encryption, fine-grained access control of medical files is carried out to ensure privacy and security as well as avoiding single point failure. Attribute-based algorithm that support multi-person democratic decision making and dynamic personnel changes are designed to make the model much closer to the real scene. Finally, through security, performance and comparing analysis with other solutions, the scheme in this paper can meet the needs of real-life scenarios in terms of security and practicability, and provides a new practical model for medical file sharing.