Spatial Index Accelerated Location Differential Privacy Protection Method

In recent years,with the rapid development of global positioning technology and mobile Internet,and the wide use of mobile terminals,location-based services are growing rapidly.The location service application will bring great convenience to people's production and life,but when users enjoy the convenience of the service,location and other sensitive information inevitably between the user and the server transmission,resulting in the probability of User's information leakage.Light is to disclose the user's eating habits,religious beliefs and other sensitive information,but also endanger the safety of user's lives,How to enable users to enjoy the service while achieving the protection of location privacy has become the focus of research.And the position K anonymous algorithm of the anonymous location privacy protection method is applied in the wide,which is mainly to achieve snapshot query privacy protection,which is vulnerable to be attacked in continuous query,therefore,How to achieve privacy protection in continuous query in location service is becoming more and more important.In this paper,to solve the problem of continuous query attack in location service,a new location privacy protection algorithm is proposed,a location K anonymous privacy preserving algorithm which is based on the differential privacy and R tree spatial index.Firstly,the nearly 50 thousand spatial data is generated by using the temporal and spatial object generator,and using the efficient indexing of R tree to storage and query processing spatial data;then the nearest neighbor query algorithm based on R tree is used to perform the generalization of the location of the target user to generate an anonymous region containing at least K users;at the same time,Taking into account the background knowledge of the attacker,this paper combines the quantitative privacy protection level and without considering the attacker's background knowledge characteristics of differential privacy.Use the K anonymous area control Laplace noise parameters,the K user points in the anonymous region were injected with noise to generate K random disturbance points,And select the disturbance point whose average distance from all users in the anonymous region is the nearest as the cluster center,generate K anonymous area as user's service request address,so as to prevent the attack of an attacker with any background knowledge.The experimental results show that the proposed location K anonymous privacy preserving algorithm which is based on the differential privacy and R tree spatial index algorithm is good not only in the area of anonymous location privacy protection effect,and the impact on the service quality of the users is small,which proved to be achieve better location services and balance of privacy protection.