As cloud computing technology matures, along with an increased application of distributed networks, increasingly larger amounts of data are being stored in the cloud, and are thus available for pervasive application. At the same time, current independent medical record systems tend to be inefficient, and most previous studies in this field fail to meet the security requirements of anonymity and unlinkability. Some proposed schemes are even vulnerable to malicious impersonation attacks. The scheme proposed in this study, therefore, combines public and private clouds in order to more efficiently and securely preserve and manage electronic medical records (EMR). In this paper, a new secure EMR authorization system is proposed, which uses elliptic curve encryption and public-key encryption, providing a health care system with both public and private cloud environments with a message authentication mechanism, allowing the secure sharing of medical resources. The analysis shows that the proposed scheme prevents known attacks, such as replay attacks, man-in-the-middle attacks and impersonation attacks, and provides user anonymity, unlinkability, integrity, non-repudiation, forward and backward security.

随着云计算技术的成熟，分布式网络应用的增多，越来越多的数据存储在云端，可供普适应用。同时，当前的独立病历系统往往效率低下，该领域以往的研究大多无法满足匿名性和不可链接性的安全要求。一些提议的方案甚至容易受到恶意冒充攻击。因此，本研究提出的方案结合了公共云和私有云，以便更有效、更安全地保存和管理电子病历（EMR）。本文提出了一种新的安全EMR授权系统，该系统使用椭圆曲线加密和公钥加密，为公共云和私有云环境下的医疗保健系统提供消息认证机制，从而实现医疗资源的安全共享。分析表明，该方案可以防止重放攻击、中间人攻击和冒充攻击等已知攻击，并提供用户匿名性、不可链接性、完整性、不可否认性、前向和后向安全性。