关键词: 轨迹流量, 差分隐私, 一致性调节, 路网约束

Abstract:

Vehicles carrying GPS equipment create large trajectory information. Analyzing and publishing trajectory data flow statistics based on road network is beneficial to the improvement of network structure and the realization of intelligent transportation. However, the direct release of trajectory traffic can lead to the disclosure of user privacy, and there is lack of a rigorous and provable privacy method to release traffic flow in road networks. Therefore, this paper presents a differential privacy trajectory flow releasing method. The method is divided into two steps: firstly, the flow value of each section is statistically calculated and the difference privacy noise is added. Secondly the post adjustment algorithm is put forward for the consistency characteristic of the flow graph, so that the adjusted flow graph not only satisfies the consistency characteristic, but also greatly reduces the publishing error. The experiment on the real road network shows that the method?has the ability to deal with large-scale network traffic, and after the optimization of the post adjustment algorithm, the release error is reduced by about 13%.

Key words: trajectory flow, differential privacy, consistency adjustment, road network constraints