The Research On Privacy Protection Model Of Continuous Location Queries Based On LBS

Information security is involved in property security,personal security and privacy security issues.With becoming important in our daily life,it becomes a popular topic in academia,and even in all society.With the birth and development of location based service,the protection of information security is a big challenge.Location service,which provide users with accurate location service,are widely applied.However,it puts users into quit dangerous situation: taking risk of information leakage while receiving location services.In the process of using the location service,how to ensure the user's location privacy is not compromised,is a crucial and practical topic.So far,the majority of scholars have done a lot of research on location services,there are using false position instead of the user's true position,separating the user ID with the user query,using pseudonyms,etc.There is a long history in location privacy protection development--from the beginning of the traditional static algorithm to recent dynamic continuous query algorithm,from the initial anonymity of a static location point,to the dynamic location of the condition of anonymity,and then to the continuous condition of a track.In this master's thesis,after analyze three representative algorithms of location privacy protection we conclude that continuous query could cause tons of network resources can be occupied,leading low resources utilization,even network congestion.Further more,it will load the burden on the anonymous server,resulting in the system's bottleneck,and in some particular situations,will lead to the leakage of the location of privacy.In this master's thesis,an improved dynamic programming algorithm is presented,which is based on the existing continuous query privacy preserving algorithm.It applies the real time trajectory to the real user's trajectory,at the same time,the k-anonymous algorithm at a certain time is extended to an anonymous algorithm within a certain period of time.The algorithm ensures the safety of privacy of the user's location information while the anonymous processing rate is improved and burden on the server is reduced.In this master's thesis,the parameters of algorithm,such as the time effect similarity,the relative position,the track distortion degree and etc.,are given a detailed definition and explanation,at the same time,it proves that the dynamic programming algorithm has better sub structure.Finally,the simulation results analysis algorithm in anonymous time,anonymous success rate,relative anonymity degree,relative spatial resolution and trajectory distortion,through performance analysis show that: the algorithm proposed in this thesis,in the basis at the expense of the anonymous time and success rate,the quality of service and the protection of privacy are well balanced.Then the simulation results shows high performance when compare with the experimental results of the existing algorithms,it proves the advantages of proposed algorithm has some advantages in anonymous time,anonymous success rate,relative anonymity degree and distortion.