Fuzzy keyword search method oriented to multi-server and multi-user

Abstract

The invention discloses a fuzzy keyword search method oriented to multi-servers and multi-users. The method comprises the steps: a data owner encrypts a clear-text set into a cipher-text set, extractsa keyword set, generates an index of a clear-text document set based on a MinHash and stores the cipher-text set and the encrypted index in a cloud server S; the cloud server S distributes the cipher-text set and the re-encrypted index to cloud servers S1, S2, ..., SN; an authorized user generates the keyword needing to be searched into a keyword fingerprint based on the Minhash to obtain a keyword trap door; and the cloud server S performs a Jaccard similarity comparison on the keyword trap door and the index and performs sorting, outputs a cipher-text document to the authorized user. According to the fuzzy keyword search method oriented to the multi-servers and the multi-users, through the use of a dimensionality reduction concept of the MinHash, fuzzy keyword search is realized; retrieval files are sorted by use of a Jaccard distance; and multi-user inquiry is realized by use of re-encryption and the efficiency of the fuzzy keyword search can be effectively improved.

Description

technical field [0001] The invention relates to the technical field of searchable encryption, in particular to a multi-server and multi-user-oriented fuzzy keyword search method. Background technique [0002] With the development of cloud computing, more and more enterprises and users outsource their data to cloud servers to enjoy convenient and fast services. However, cloud servers are not completely trustworthy and may pose a great threat to user data privacy. In order to protect sensitive data from being leaked, users will first encrypt the data and then store the data in the cloud server. Therefore, how to search for the required documents in a large number of ciphertexts has become a difficult problem. [0003] In order to better solve the problem of ciphertext retrieval, Song et al first proposed a searchable encryption method. In order to improve the search efficiency, Chang et al. proposed to build corresponding indexes for each document to improve the retrieval e...

AI Technical Summary

Problems solved by technology

Based on the hybrid structure, the literature proposes a searchable encryption system that realizes keyword precise retrieval and fine-grained access control to encrypted data. However, this scheme allows the server to obtain keyword information, which has a high security risk.

[0006] For security and performance considerations, big data owners expect to store massive amounts of data separately in multiple cloud servers, which poses a huge challenge to the single-server model

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