云环境下用户隐私混合加密方案及其性能分析

Hybrid encryption scheme and performance analysis for user's privacy in cloud

针对云环境下用户隐私数据的安全性和数据应用操作效率要求相矛盾的问题,提出了一种基于同态加密和基于属于加密的混合方案,实现对云用户隐私信息进行分类加密保护。方案中将用户数据分为绝对保密的数据和可信用户合理访问的数据2类,其中对绝对保密的数据采用同态加密算法;对可被部分授权用户访问的数据制定相应的访问控制树,并采用基于属于的加密算法。设计了云环境下混合加密方案,分为客户端和服务端,并将混合加密方案与基于属性的加密方法从加解密时间和存储开销进行了比较,可以看出混合加密方案具有很好的应用前景。

Due to the paradox between the security of user＇s privacy data and the efficiency of application operation,a solution combined the homomorphic encryption with the ABE（ attribution based encryption） is proposed here. This solution divides the users＇ privacy into absolute secret data and the data which can be visited by trusted users. The absolute secret data was used by homomorphic encryption,and the data visited by authorized user firstly made the access control tree and was used by ABE. In the final part,a prototype system for the hybrid solution is designed and divided into customer end and server end. In order to verify the solution,we compared with ABE by encrypted time,decrypted time and storage used. The results indicated that the hybrid solution could be applied best.