A Dummy Trajectory Privacy Protection Scheme For Trajectory Publishing Based On The Spatiotemporal Correlation

With the rapid development of wireless communication and mobile terminal,the Location-Based Service(LBS)has become an indispensable part of daily life.However,while people enjoy the convenience of LBS,they also face with the risk of location and trajectory leakage,such as home address,religious beliefs and so on.Because of the correlation between the front and rear locations of trajectory,attackers are more likely to speculate the user ’s privacy information from trajectory than a single location.Therefore,research on the trajectory privacy protection of LBS is of great significance of the promotion of LBS.Since dummy trajectory method guarantees the integrity of trajectory data with no need for a trusted third party which is easy to become a bottleneck,it has been widely used to protect the user ’s trajectory privacy in trajectory publishing.However,the existing dummy trajectory schemes do not consider the spatiotemporal correlation between neighboring locations in a trajectory,and ignore the spatiotemporal correlation among the generated trajectories.If user uses the existing dummy trajectory schemes to protect,attackers can correctly infer some dummy trajectories to improve the probability of identifying the user ’s real trajectory,or even to identify the real trajectory.In order to solve these problems,in this paper,the research and exploration are made on the problem of dummy trajectory privacy protection for trajectory publishing.Firstly,we propose a dummy trajectory identification scheme,and then propose a dummy trajectory privacy protection scheme for trajectory publishing based on the spatiotemporal correlation.The main research of this paper includes:1.Aiming at the shortcomings of the existing dummy trajectory privacy protection scheme,we propose a dummy trajectory identification scheme in trajectory service,which identifies the dummy trajectory from the percentage of path that satisfies the time reachability and the degree of each location in the trajectory.2.We deeply analyze the movement mode of trajectory and proposed a dummy trajectory privacy protection scheme based on the spatiotemporal correlation.In this paper,we consider the overall direction of trajectory,the reachable time and moving distance between neighboring locations and degree.3.By the experimental simulation,we validity the effectiveness of the dummy trajectory identification scheme.Firstly,the dummy trajectories are generated by the existing dummy trajectory scheme.And then we used proposed scheme identified them.A large number of experiments show that the proposed scheme can identify the dummy trajectories with high success rate.And then,security analysis shows that the presented dummy trajectory scheme successfully confuses the user’s real trajectory with dummy trajectories,thereby protecting the user’s trajectory privacy.Furthermore,extensive experiments indicate that the presented scheme not only has the limited computation cost,but also ensures that the generated dummy trajectories are similar to the user’s real trajectory.