A fuzzy multi-keyword retrieval method for ciphertext data in cloud environment

Abstract

The invention discloses a fuzzy multi-keyword retrieval method of encrypted data in cloud environment. A file is subjected to set encryption by a data owner to generate a ciphertext file; keywords are extracted from each file; the keywords are subjected to binary segmentation and vectorization to obtain a binary vector group; the binary vector group is subjected to dimensionality reduction and is then inserted into a counting type bloom filter to generate index vectors; each index vector is encrypted to obtain a security index; the ciphertext file and the security indexes are sent to a cloud server; a pre-authorized data user or the data owner extracts the keywords from query data; binary segmentation and vectorization are performed to generate a query vector; encryption is performed to obtain a trap door; the trap door is sent to the cloud server; the cloud server obtains a certain number of files with the highest relevancy degree through query according to the trap door and the security index; after sorting, the files are returned to the data owner. The large data volume of ciphertext multi-keyword retrieval is supported; compared with the prior art, the method has the advantages that the index building and query processes are more efficient; the sorting result is more accurate; the data privacy is effectively protected.

Description

technical field [0001] The invention belongs to the technical field of cloud computing and information retrieval, and more specifically relates to a fuzzy multi-keyword retrieval method for ciphertext data in a cloud environment. Background technique [0002] Cloud computing can provide users with more efficient and cheap computing, storage and application services on the Internet. More and more enterprises and individuals are willing to store data in cloud servers and retrieve the data when needed. However, after users store data in the cloud environment, they lose direct control over the data, which may lead to the leakage and abuse of user privacy information. For example, Google and other cloud service providers have experienced data leakage or loss of user data. Data stored in the cloud environment faces greater security issues. It not only prevents network hackers from illegally obtaining data, but also prevents cloud service providers or outsourced database service p...

AI Technical Summary

Problems solved by technology

[0009] To sum up, there is currently no safe and efficient ciphertext retrieval method that supports fuzzy multi-keywords in the cloud environment. Existing related solutions do not support fuzzy queries or multi-keyword queries, and the query efficiency is low. Large space overhead and other issues

Images