Pricacy-Preserving Dynamic Fuzzy Multi-Keyword Ranked Search Over Encrypted Cloud Data

With the further development of cloud computing, more and more users and enterprises send data and information to the cloud for storage, which can not only save money, but also free users from the complexity of the local data management. When we gain many advantages from the development of cloud computing, at the same time, reliability and security of cloud storage is paid more and more attention by cloud users. In order to ensure the security and privacy of data, data is commonly stored in the form of ciphertext on the cloud server, so that it is difficult for users to search on the ciphertext data.In this paper, according to the characteristics of cloud environment, to solve the problem of efficiently dynamic fuzzy multi-Keyword ranked search over encrypted cloud data, this paper present a pricacy-preserving dynamic fuzzy multi-keyword ranked search over encrypted cloud data scheme(namely DFEMRSE scheme). DFMRSE scheme presented in this paper references building concepts of MRSE scheme, and makes many improvements than MRSE. First, by introducing TF x IDF rule and bloom filter to MRSE scheme and proposing mechanisms of separating blocks with erasure-correcting codes, EMRSE becomes more accurate and more efficient than MRSE, at the same time, EMRSE scheme is made necessary optimizations; Secondly, by using wildcard and thesaurus to build fuzzy sets and proposing the bloom filter of supporting wildcard-fuzzy keywords for search, FEMRSE can support fuzzy keyword search than MRSE; Finally, through the use mechanisms of separating blocks with erasure-correcting codes、incremental mechanism,as well as the nature of vector and matrix multiplication, DFEMRSE implements dynamic file operations (including increasing file operation, deleting file operation, updating file operation) than FEMRSE.This paper conducts simulation experiments for DFEMRSE scheme and compares with MRSE scheme. The results show that, under the precondition of ensuring the security of search, DFEMRSE scheme not only can achive efficient and accurate multi-keyword ranked search in cloud environments, but also can achive quick and efficient fuzzy keyword search and dynamic file operations.