IFTS: A Location Privacy Protection Method Based on Initial and Final Trajectory Segments

Jiuyun Xu,Leyi Shi,Qiang Duan,Ruru Zhang,Lele Liu,Jin Xie

doi:10.1109/access.2021.3052169

Abstract

Privacy protection problem is one of the most concerning issues related to Location-Based Services (LBS) in our daily life. Privacy protection of LBS often requires anonymizing customer's trajectory data. Currently available methods for trajectory anonymity often assume an entire trajectory as one anonymous unit, which may lead to low anonymity efficiency due to the massive amount of trajectory data, especially for customers travel through a long road. Considering people's routine activities, the starting and ending locations of a trip often uncover the user's request intent, which may lead to exposure of user privacy. In order to address the problem of inefficient trajectory anonymity, we propose a location privacy protection method that is based on the initial and final trajectory segmentation (IFTS) in this paper. In the IFTS method, the road network structure is first transformed into an edge cluster model based on its location type. Then, the user trajectory is divided to segments according to the temporal sequence of the ingress and egress nodes. The initial and final trajectory segments are identified and divided into equivalence classes, which then are used for constructing a trajectory graph and the corresponding k-anonymous set. Our experimental results show that the proposed method can reduce the anonymous area, improve anonymity efficiency, and enhance trajectory data utilization compared to the existing methods for trajectory anonymity.

Highlights

In today’s life, the mobile device of a customer using a Location based Service (LBS) often needs to constantly send its location information to the service provider
In this paper, we proposed the IFTS method for location privacy protection based on the initial and final trajectory segments for addressing the problem of low trajectory anonymity efficiency in the traditional trajectory anonymous protection technologies
The proposed method divides the entire trajectory in a chronological order and selects only the initial and final trajectory segments of each trajectory for constructing an anonymity area

Summary

INTRODUCTION

In today’s life, the mobile device of a customer using a Location based Service (LBS) often needs to constantly send its location information to the service provider. Xu et al.: IFTS: A Location Privacy Protection Method Based on IFTS position A to position B through a fixed route in the morning and returns from B to A in afternoon on each workday but basically stays at A during weekends, the attacker may reasonably predict that A and B are the user’s home address and work address respectively This example demonstrates that compared to protection of the entire trajectory, anonymity of the initial and final segments of the trajectory may be more effective in protecting the user’s location privacy and may reduce the anonymous area thereby improving data availability and anonymity efficiency.

RELATED WORK

ROAD NETWORK CONVERSION Definition 3

SECURITY ANALYSIS

CONCLUSION