Forward Secure Searchable Encryption over Medical Cloud Data

In medical cloud computing, medical data (e.g., electronic health records and diagnostic report) are allowed to be outsourced to the remote cloud server. Since cloud service providers are semi-trusted, it is important to protect the privacy of medical data while ensuring the convenient access of stored data. Several schemes have been proposed for this purpose. In this paper, we propose a novel scheme for high-dimension medical data based on searchable symmetric encryption (SSE) and locality sensitive hashing (LSH), which is able to provide greater security for the stored on the medical cloud—forward privacy, while ensuring efficient search and update performance. Combined with the experimental results, we carried out a detailed security analysis and performance analysis of the proposed scheme. The results show that the server cannot observe which query request is associated with the update object. Therefore, the proposed scheme is forward secure and efficient in practice.