Attribute-based encryption and zk-SNARK authentication scheme for healthcare systems

In recent years, the widespread adoption of electronic medical systems has improved the efficiency of diagnosis and treatment. However, the security of physician identity authentication and the protection of patient privacy face serious challenges. Existing biometric-based authentication schemes pose risks of privacy leaks, while attribute-based schemes that support fine-grained access control often lack efficient user revocation and tracking mechanisms. To address this critical need, this paper proposes an innovative authentication protocol that integrates attribute-based encryption (ABE) with zk-SNARK zero-knowledge proofs. This scheme achieves zero-knowledge identity verification to protect biometric privacy, supports efficient fine-grained access control and dynamic attribute revocation through ABE, and integrates malicious user tracking capabilities to ensure accountability. Through security analysis and performance evaluation, we have verified that the protocol possesses traceability, resistance to collusion attacks, anonymity, unforgeability and correctness. It provides a secure, privacy-first and practical solution for healthcare systems, with potential applicability to other sensitive domains such as finance and e-government.