Research On LBS Location Privacy Protection Mechanism Based On Ciphertext Search

Location-based service(Location-based Service,LBS)system is a combination of existing mobile communication networks,wireless sensor networks and global positioning system(Global Positioning System,GPS),which combines various existing location technologies and data processing schemes and brings together all kinds of location-related services and businesses so as to provide location-based information services for users.With the further development of LBS service,how to effectively protect users' privacy information and provide accurate services is becoming an urgent problem on the condition of efficient services provided by service providers.Experts and scholars have put forward a large number of solutions.Although the existing mainstream solutions can provide the basic protection privacy of user,the accuracy of service is not satisfactory.This thesis aims to further improve the privacy of user protection scheme and explore ways to improve service accuracy.From the perspective of privacy protection of LBS service,the security model of location privacy protection is defined based on location privacy and query privacy leakage in LBS service.Model of LBS location privacy protection based on searchable encryption(LBS location privacy protection based on searchable encryption,LBSPP-BSE)and its specific algorithm are proposed,realizing LBS location privacy protection based on ciphertext search and improving service accuracy.Aiming at the problems of LBS scheme in practical applications,privacy protection and service precision,the contribution of this paper is embodied in three aspects:(1)we proposed a secure and effective LBS location privacy protection system,which is based on efficiency ciphertext search.(2)We effectively protect the location and query privacy of LBS users by introducing the third-party key mechanism to encrypt the location information and query information of the users,moreover using ciphertext in query.(3)This scheme improved the accuracy of the LBS by directly encrypting the location information of users and never creating false location.Finally,the paper strictly proves the correctness of ciphertext search and decryption,verifies the correctness of the designed scheme,and proves the security attributes of the scheme through security analysis.The scheme can resist the attack of unauthorized users based on background knowledge and the collusion attack of unauthorized users.The communication cost of this paper design is large,so need further research and exploration.