A Hybrid Method of User Privacy Protection for Location Based Services

Recently, highly accurate positioning devices enables us to provide various types of location based services (LBS). On the other hand, because such positioning data include deeply personal information, the protection of location privacy is one of the most significant problems in LBS. Lots of different techniques for securing the location privacy have been proposed, for instance the concept of Silent period, the concept of Dummy node, and the concept of Cloaking-region. However, many of these researches have a problem that quality of the LBS (QoS) decreased when anonymity is improved, and anonymity falls down when QoS is improved. In this paper, we present a node density-based location privacy scheme which can provide location privacy by utilizing hybrid concept of Dummy node and Cloaking-region. Simulation results show that the probability of tracking of a target node by an adversary is reduced and the QoS of LBS is also improved.