Location Privacy Technology Research In Location Based Services

With location based service(LBS)becoming more and more popular,protecting location privacy of users has become an important task.In daily life,all kinds of application software will use LBS to fulfill the needs of users,but while enjoying the convenience and benefits provided by LBS,users may leak the user's location privacy to attackers.The increasingly widespread use of LBS in daily life and the increasing number of users using LBS make the location privacy of users face more severe challenges.In order for users to enjoy various personalized services(navigation,games,information services,etc.)provided by LBS while ensuring the user's location privacy,a safe and effective location privacy protection scheme has become the key.Therefore,reducing the risk of user location privacy leakage and improving service quality have become the focus of research.The main research work on location privacy protection in this article is as follows:(1)Study the current situation of location privacy at home and abroad,and deeply understand the protection methods and principles of location privacy at home and abroad.Through the comparative analysis of the advantages and disadvantages of various methods,and combined with some mainstream attack models and methods,this paper selects the location privacy protection technology based on twist method,which is more practical and more anti-attack,as the main content of this paper.(2)Aiming at the unbalanced distribution of query results in Space Twice scheme,this paper proposes a location privacy protection method based on double anchors combined with the road network environment under the distributed system structure.Users can build an anonymous area according to their own privacy needs,and use anchors as query points to conduct incremental nearest neighbor query based on double anchors,so as to make the query results more balanced and improve the query accuracy rate.The advantages of this method are: users can build anonymous area according to the road network environment and their privacy requirements,so as to ensure that the anonymous area is more accurate;when users select anchor points,they can quickly select appropriate anchor points according to the distribution of points of interest.It can not only ensure the controllable cost,but also meet the requirements of users;by adding a round of supplementary queries after the incremental neighbor query ends,while improving the accuracy of the query results,the query range is reduced and the query efficiency is improved.(3)Aiming at the problem of low efficiency of the traditional nearest neighbor query method,this paper proposes a location privacy protection method based on Voronoi diagram.The points of interest based on Voronoi partition are indexed by the cross partition quadtree of plane region,the fast retrieval of interest points of the nearest neighbor is realized,which greatly improves the query efficiency compared with the traditional nearest neighbor query.At the same time,the client does not need to obtain the plane area partition quadtree structure from the LBS server before sending the query request,which reduces the communication overhead between the client and the LBS server.In terms of privacy protection,this method does not need to construct an anonymous area,but selects a suitable dummy location instead of the real location to send a query request,avoids the leakage of the real location,protects the user's location information,and reduces the calculation cost of the user.By experimenting with this method in different road network environments,the experimental results show that this method can not only ensure the privacy of users' location,but also improve the service quality of query.