Similarity test for privacy-preserving medical data sharing based on NTRU encryption

Recently, how to share the encrypted data efficiently from the cloud service provider becomes a hot topic, and massive research works have studied on Equality Test for encryption files of secure cloud storage. The basic idea of sharing information is to find the encrypted target information. Considering the scheme of identity-based encryption with equal test (IBEET) is defined as a feasible scheme, but it can only search for ciphertext composed of identical plaintext. However, the above technologies have seriously affected information sharing, because it greatly limits the search scope. Especially in some special areas, such as medical industries, doctors need to share similar medical information for auxiliary treatment and autonomous learning to improve the personal business ability. We propose the similarity test for sharing the privacy-preserving medical information in cloud environment. Our scheme proposal focuses on the Locality-Sensitive Hashing function to generate the index for protecting the upload information. In addition, our scheme utilizes the identity based on NTRU encryption to achieve resistance to quantum attacks.