云环境下支持多授权机构的医疗数据安全共享方案

在当前的云环境下，医疗数据存储的研究中存在着隐私信息外泄，机构之间数据共享效率较低等问题。因此，针对云环境下电子医疗数据的安全共享需求，提出了一种支持多属性机构的基于属性的密文策略加密方案，实现了加密医疗数据的细粒度访问控制。通过在加密阶段引入离线计算和在解密阶段引入外包计算，所提方案显著降低了加解密延时，提高了医疗数据访问控制的效率。安全性分析和性能分析表明所提方案满足可重放适应性选择密文攻击安全性，且在性能上优于已有的方案，提高了云环境下医疗数据共享的安全性和效率。

Medicaldata secure sharing scheme supporting multi-authority in cloud environment

In the current cloud environment, research on medical data storage faces issues such as privacy information leakage and low data sharing efficiency among institutions. Therefore, in response to the demand for secure sharing of electronic medical data in a cloud environment, it proposed a ciphertext policy-based attribute encryption scheme supporting multi-authorities. This scheme achieved fine-grained access control for encrypted medical data. By introducing offline computation during encryption and outsourcing computation during decryption, the proposed solution significantly reduced encryption and decryption latency, thereby enhancing the efficiency of medical data access control. Security analysis and performance evaluation demonstrate that the proposed scheme satisfied the security requirements against chosen ciphertext attacks with replay adaptivity and outperforms existing solutions in terms of performance. This contributes to improving both the security and efficiency of medical data sharing in a cloud environment.