Research On Efficient And Secure Fuzzy Search Over Encrypted Data In Cloud Computing

With the rapid development of cloud computing technology,the advantages of it,such as large scale,high availability and on-demand service,have attracted more and more attention.Outsourcing data services to the cloud allows organizations to enjoy not only monetary savings,but also simplified local IT management.In order to reduce the risk of data leakage,data must be encrypted before outsourcing.Searchable encryption is a important technology of privacy-preserving in cloud computing.Among them the ciphertext-based fuzzy keyword search scheme,which allows users to input small errors and inconsistencies in the form,greatly improves the usability of the system and the.user's search experience.Previous fuzzy keyword search schemes have two shortcomings:1)the main drawback of their scheme is the requirement of a predefined dictionary that covers possible keyword misspellings,making searches inefficient.2)multi-keyword fuzzy query needs multi-round operation,and it does not support a round operation.In order to achieve efficient fuzzy query,this paper presents a basic scheme of wildcard-based multi-keyword fuzzy search(WMFS),which uses the definition of prime that it can only be factored into 1 and itself.The keywords containing wildcard characters were transformed into vectors,and the matching algorithm based inner product between the index and the trapdoor is executed.If the value is an integer,the files match.This paper also proposes an advanced scheme that is more secure than the basic scheme and can resist the choice of plaintext attacks to protect user privacy.Compared with existing secure fuzzy search schemes,our WMFS scheme has the following merits:1)Efficiency.WMFS eliminates the requirement of a predefined dictionary and thus,enables efficient searches.2)High accuracy.WMFS reduces false positives and false negatives introduced by specific data structures and allows a user to retrieve files as accurately as possible.3)Flexibility.WMFS supports keyword and substring matching to achieve different search patterns.