Computationally Recoverable Camouflage: A Universal Model for Privacy-Aware Location-Based Services

TL;DR

This paper introduces a universal privacy-preserving model for location-based services that allows users to adjust their location data's privacy level while maintaining service quality, using scalable camouflage and fine-grained access control.

Contribution

The paper proposes a novel CRC model with a scalable camouflage algorithm considering context, and applies SCP-ABE for fine-grained access control, demonstrating efficiency on Android devices.

Findings

The CRC model effectively balances privacy and service quality.

The camouflage algorithm provides formal privacy guarantees.

Implementation shows computational efficiency on mobile devices.

Abstract

With the prevalence of location-based services (LBSs) supported by advanced positioning technology, there is a dramatic increase in the transmission of high-precision personal geographical data. Malicious use of these sensitive data will threaten the privacy of LBS users. Although privacy research in LBSs has received wide attention, related works are mostly focused on some specific applications. Due to high diversity of LBSs, it is critical to build a universal model that is able to handle privacy protection for broader range of applications. In this paper, we propose a Computationally Recoverable Camouflage (CRC) model, where LBS users can preserve privacy by reporting camouflaged location information and are able to flexibly leverage between the service quality and the achieved privacy in different applications by adjusting the precision of the camouflage information. In particular, we propose a novel camouflage algorithm with formal privacy guarantee that considers both location context and social context, enabling LBS users to scalably expose camouflage information in terms of two dimensions. Furthermore, we apply the Scalable Ciphertext Policy Attribute-Based Encryption (SCP-ABE) algorithm to enforce fine-grained access control on the two-dimensional-scalable camouflage information. Through successful implementations on Android devices, we have demonstrated the computational efficiency of the proposed CRC model.