A Location Point Privacy Protection Method Based On Location Service

In recent years,the ratio of people using location-based services in their daily lives is getting higher and higher because of the continuous innovation of mobile networks and GPS technology.Although location-based services can bring great convenience to people,users' geographic information is not safe,and it most likely has been leaked.An attacker who obtains user's information can infer the user's house,frequent places,social relationships and so on through existing technology.Many researchers are paying more and more attention to how mobile users can get both high-quality protection of location privacy and high-quality services.Although the existing methods can protect the location privacy of users,the results obtained from the server will also be biased.The existing methods have been balancing the protection of location privacy and service quality.Regarding the above problems,this paper proposes a method of location-based privacy protection based on quality of service,which can protect the location privacy of mobile users while obtaining nearly perfect quality of service.The main research contents are as follows:(1)This paper proposes a service quality loss function loss(ORS,RRS)based on real query results in order to quantitatively judge the quality of service,where RRS is the real query result set and ORS is the obfuscated query result set.The service quality loss function is a novel evaluation index based on real query result set.(2)A location point privacy protection algorithm based on Voronoi Diagram and historical points is proposed,which can generate obfuscated location point to ensure that the query results returned by the real location point and the obfuscated location point to the location-based server are the same.thereby achieving the purpose of protecting the user's location privacy while achieving the purpose of lossless service quality.(3)A location privacy protection algorithm based on the maximum loss threshold(Tmax)is proposed.Tmax is the maximal acceptable service quality loss for the user.The time to get the algorithm result is too long.So this paper proposes a pruningenumeration algorithm and Voronoi Diagram enumeration algorithm optimize the algorithm in order to reduce calculation time effectively.(4)This paper uses a real data set for a comprehensive experimental evaluation.The experimental results show that the algorithm can generate anonymous area that meet the condition.In addition,this paper also discusses the effect of the maximum privacy threshold Tmax on the results,and compares the calculation time of the pruning enumeration algorithm and the Voronoi Diagram enumeration algorithm.Finally,the location-based privacy protection algorithm based on quality of service is compared with other methods.The experimental results show that the algorithm in this paper is better than other methods.