Research On Efficient Ranked Multi-Keyword For Multiple Data Owners In Cloud Computing

With the development of cloud storage,more data owners are inclined to outsource their data to cloud services.For privacy concerns,sensitive data should be encrypted before outsourcing.There are various searchable encryption schemes to ensure data availability.However,the existing search schemes pay little attention to the efficiency of data users' queries,especially for the multi-owner scenario.In contrast to the single-user scenario,developing an efficient multiple data owners scheme becomes a new challenge.The paper focuses on the issues of security and privacy protection in the cloud environment.The main contributions of this paper are listed as follows.(1)In this study,we proposed a tree-based ranked multi-keyword search scheme for multiple data owners(TBMSM).Specifically,by considering a large amount of data in the cloud,we utilize the TF×IDF model to develop a multi-keyword search and return the topk ranked search results.To enable the cloud servers to perform a secure search without knowing any sensitive data(e.g.keywords and trapdoors),we construct a novel privacypreserving search protocol based on the bilinear mapping.To achieve an efficient search,for each data owner,a tree-based index encrypted with an additive order and privacy-preserving function family is constructed.The cloud server can then merge these indexes effectively,using the “Depth-first Search” algorithm to find the corresponding files.Finally,the rigorous security analysis proves that our scheme is secure,and the performance analysis demonstrates their efficacy and efficiency.(2)Based on Ceph,we designed and implemented an efficient multi-keyword search system.We built a Ceph distributed file storage system based on the campus network IPv6 network environment,which provides secure,reliable,and easily scalable storage and computing services for IPv6 tenants.We established a security query technology framework aims at data security and privacy protection,and provide users with secure data sharing and query services.Finally,we used the text categorization corpus of Fudan University to evaluate the system,the performance analysis shows that the system achieves efficient multi-keyword search under the premise of ensuring data security.