Secure multi-keyword search with user/owner-side efficiency in the cloud

As the amount of data in the cloud grows, ranked search system, the similarity of a query to data is ranked, are of significant importance. on the other hand, to protect privacy, searchable encryption system are being actively studied. In this paper, we present a new similarity-based multi-keyword search scheme for encrypted data. This scheme provides high flexibility in the pre and post-processing of encrypted data, including splitting stem/suffix and computing from the encrypted index-term matrix, demonstrated to support Latent Semantic Indexing(LSI). On the client side, the computation and communication costs are one to two orders of magnitude lower than those of previous methods, as demonstrated in the experimental results. we also provide a security analysis of the proposed scheme.