Research On The Encryption Technology Of Multi-keywords Public Key Searchable Encryption In Cloud Storage

With the popularization of smart devices and the development of network technology,more and more people begin to select the services provided by cloud service providers to store personal privacy information.Users can enjoy the convenience offered by the cloud services,meanwhile the security of users' privacy data such as diaries,photos,chat records face severe challenges.In order to improve the security of cloud storage,the cloud service providers usually store encrypted data to protect the users' privacy,but this method is a difficult and complex task for the retrieval of cipher text.So the search of encrypted data becomes a hotspot,this paper will focus on the scheme of cipher text search and the key technology in the cloud storage.Keywords searchable encryption scheme is one of the common methods of the encrypted data retrieval.It includes single keywords and multi-keywords scheme.For single keyword searchable encryption scheme,there are symmetric encryption and public key encryption,in this piece linear search technology and security index technology that use the symmetric encryption,while in public key encryption scheme,there are PEKS based on bilinear as well as the improvement of PEKS.Multi-keywords searchable encryption,mainly introduced PECK scheme based on bilinear pairings and the scheme based on elliptic curve,the former can solve the problem of multi-keywords matching,but it uses a large number of pairings,reduces the efficiency of the algorithm,the latter reduces the use of bilinear pairings,but the keywords search must be ordered,if the searcher does not know the original position of search keywords in the keywords set,then the server cannot match them.Due to the shortcomings of these two multi-keywords searchable encryption schemes mentioned above,in this paper the scheme based on a multi-keywords disorderly matching is proposed.The scheme use the matrix multiplication between the search keywords set and the cipher text of multi-keyword set,if the search keywords are included in the multi-keywords set,then the number of the same element in result matrix is equal with the quantity of the search keywords set.The searcher does not need to remember the location of the original keywords.This scheme can solve the problem of multi-keywords disorderly matching,and it also has lower computational complexity.This paper will analysis the security of this scheme,then do experiment to verify it.