Research on Privacy Protection Method of User Activity Area Trajectory Based on Noise Prefix Tree

Track-based services, such as DiDi and bike-sharing, are becoming increasingly popular. However, Existing trajectory data protection methods are difficult to balance the privacy and usability of data, and there are disadvantages of short trajectory distance and easy waste of privacy budget in the process of publishing privacy protection algorithms, so this paper proposes a privacy protection method of user activity area trajectory based on noise prefix tree. This method reduces the query time by building a noisy prefix tree to improve efficiency. At the same time, a user activity area is proposed to replace the location points in the area with core points. In this way, the degree of privacy protection can be improved, and the trajectory can be simplified. Finally, experiments are designed to verify the effectiveness of the proposed algorithm and its superiority compared to traditional algorithms.