A Location Privacy-Preserving System Based on Query Range Cover-Up or Location-Based Services

TLDR

Location‑based services are widely used in industry and daily life, yet they pose a serious threat to users' location privacy because of increasingly untrusted server‑side components. This work proposes a privacy‑preserving system for LBS that protects query ranges by constructing cover‑up ranges. The system employs a client‑side framework, a formal privacy model defining constraints for ideal cover‑up ranges, and an implementation algorithm that satisfies these constraints without sacrificing service accuracy. Theoretical analysis and experiments demonstrate that the system effectively enhances location privacy on untrusted servers while maintaining LBS accuracy and usability.

Abstract

Location-based service (LBS) has been widely used in various fields of industry, and become a vital part of people's daily life. However, while providing great convenience for users, LBS results in a serious threat on users' location privacy, due to its more and more untrusted server-side. In this article, we propose a location privacy-preserving system for LBS by constructing "cover-up ranges" to protect the query ranges associated with a location query sequence. Firstly, we present a client-based system framework for location privacy protection in LBS, which requires no compromise to the accuracy and usability of LBS. Secondly, based on the framework, we introduce a location privacy model to formulate the constraints that ideal cover-up ranges should satisfy, so as to improve the efficiency of location services and the security of location privacy. Finally, we describe an implementation algorithm to well meet the location privacy model. Both theoretical analysis and experimental evaluation demonstrate the effectiveness of our system, which can improve the security of users' location privacy on the untrusted server-side, without compromising the accuracy and usability of LBS.