Research And Implementation Of Privacy Protection Method Based On Location Services

In recent years,with the continuous development of wireless communication technology positioning technology,smart terminal devices are widely used,resulting in people's lifestyle and working methods relying more and more on mobile terminal devices,making the current location-based services(Location-based Service),LBS)is increasingly popular.When a user uses the LBS service,the mobile device needs to rely on the mobile device to send its location to the location service provider to obtain the corresponding location service.However,while LBS gives great convenience to the public,personal location information is often leaked.When the user's location information is attacked by a malicious attacker or sold by a malicious location service provider,it will cause immeasurable loss to the user.Therefore,in order to protect the user's personal location information from being leaked,the privacy protection issue of LBS has received wide attention from all walks of life.This paper studies the privacy protection of LBS for both snapshot and mobile trajectory.main tasks as follows:(1)Aiming at the problem of low user credibility and excessive anonymity in the snapshot phase,a location privacy protection method based on similar user area sensitivity(SUAS)is proposed.Firstly,the method divides the entire area according to a quadtree structure.Then,when the user issues a location service request,the user who has a position drift near the requesting user is removed.The other users are sorted according to the similarity degree of the attributes,and k-1 users with high similarity are preferentially selected to form a k-anonymous group.Finally,when constructing the anonymous area,the bottom-up method is used for construction.Based on the traditional L-diversity,this paper adds regional sensitivity to measure the security of anonymous areas,so that the final anonymous results meet the user's privacy needs.(2)Aiming at the problem of low availability and low anonymity of trajectory anonymous long-term trajectory data,a location privacy protection method(IFTS)based on initial and finial trajectory segments is proposed.Firstly,the method transforms the road network structure into an edge cluster model based on location type.Then,all the trajectories are preprocessed,the whole trajectory is segmented according to the time sequence of the ingress and egress nodes,and the starting and ending trajectory segments in each trajectory are identified,and the equivalence classes are divided according to the distance.Finally,the initial and finial trajectory segments in the equivalence class are built into the trajectory segment graph,and the weight of the edge is set as the comprehensive parameter of the distance and position type difference of the trajectory segments,and according to the weight value,the corresponding k-anonymous set is formed,and the anonymous result is obtained.(3)Through experiments,the SUAS method has certain improvements in the degree of location privacy protection and quality of service.The IFTS method improves the availability of data and the efficiency of anonymity to some extent.