Research And Implementation Of Dummy Trajectory Generation Based Trajectory Privacy Protection In Road Network

In recent years,with the rapid development of intelligent mobile devices and mobile sensing technology,the location-based service has become an indispensable part of people's daily life.While users enjoy the convenience of those applications,the user's location and trajectory information are constantly being collected from those applications.If those collected data are directly published without processing,it will bring serious security risks to the user's personal privacy.Therefore,how to protect the location and trajectory data privacy security are not only highly valued by the government organization,but also cause widespread concern by domestic and foreign scholars.However,the existing dummy-based trajectory privacy protection technology does not consider the spatiotemporal features of the user's trajectory in the road network.For that reason,the generated dummy trajectories can be easily identified by attackers,which may cause serious privacy leakage.To solve this problem,I propose a dummy trajectory generation based algorithm for trajectory privacy protection in the road network,named RDTPP,to protect use's trajectory privacy.The main idea of RDTPP algorithm is to generate k-1 dummy trajectories which satisfy the spatiotemporal constraints of road network trajectory and make them similar to the use's trajectory mobile pattern,and then construct a trajectory set with use's trajectory and these dummy trajectories in order to protect use's trajectory privacy.RDTPP algorithm uses real road network map data to construct a road network undirected graph,to ensure that the generated dummy trajectory satisfies the spatiotemporal accessibility constraint of the road trajectory,so that the generated dummy trajectories could not be identified by that adversaries.In RDTPP algorithm,it also proposes to use the measurements of the trajectory similarity and the information loss to make the generated dummy trajectories and the user's trajectory indistinguishable in the motion mode,which reduces the information loss of the publishing trajectory set.RDTPP algorithm and existing methods are evaluated based on the real trajectory data set,and the results show that the RDTPP algorithm can effectively protect the privacy of the use's road network trajectory,meanwhile it can ensure the high data utility of the published trajectory set.