Medical Data Classification Encryption Sharing Scheme Based on Blockchain
When sharing medical data,the volume of shared data often exceeds the neces-sary amount,leading to significant computational overhead when encrypting a large num-ber of metadata.This paper proposes a medical data classification encryption and sharing scheme based on blockchain,which integrates attribute-based encryption and blockchain to facilitate access control and data sharing of medical information.First,the entire med-ical dataset is classified into medical metadata according to the basic information,medical departments and disease types,enabling fine-grained access control.Then,a data access strategy classification algorithm is proposed,which divides the data access strategy into attribute encryption strategy and blockchain access strategy.Multiple attribute encryp-tion strategies are combined to reduce the computational cost of constructing the access structure tree.Smart contract controls the access of the data on the chain according to the blockchain access policy,and the authority is revoked by modifying the blockchain policy.Finally,the security analysis and simulation experiments validate the feasibility and effi-ciency of the proposed scheme.