Blockchain-Based Multiple Authorities Attribute-Based Encryption for EHR Access Control Scheme

The Internet of Medical Things (IOMT) is critical in improving electronic device precision, dependability, and productivity. Researchers are driving the development digital healthcare systems by connecting available medical resources services. However, there concerns about security sharing patients’ health records. In response to prevailing problems such as difficulties records between different hospitals inability grasp usage their records, we propose a patient-controlled cloud-chain collaborative multi-authority attribute-based encryption for EHR with verifiable outsourcing decryption hiding access policies (VO-PH-MAABE). This scheme uses blockchain store validation parameters utilizing its immutable, which data users use verify correctness third-party results. addition, policy-hiding technology protect privacy so that guaranteed. Moreover, establish trust among multiple authorities utilize Shamir secret smart contracts compute keys or tokens attributes managed across administrative domains, avoids single point failure reduces communication computation overhead on user side. Finally, ciphertext indistinguishability under chosen plaintext attack demonstrated stochastic prediction model compared other schemes terms functionality, overhead, overhead. experimental results show effectiveness this scheme.