Enabling Location Privacy in Wireless Personal Area Networks ⋆ Dave Singel´ ee * Bart Preneel ESAT-COSIC Katholieke Universiteit Leuven Heverlee, Belgium Abstract Location privacy is one of the major security problems in a Wireless Personal Area Network (WPAN). An eavesdropper can keep track of the place and time mobile devices are communicating. The hardware address of a device can often be linked to the identity of the user operating the mobile device; this represents a violation of the user’s privacy. In this paper, we consider four communication scenarios and present several techniques to solve the location privacy problem in each of these scenarios. We will also show that these scenarios are related to each other. As mobile devices in a WPAN are typically operated by a user and energy constrained, we focused on user-friendliness and energy consumption during the design of our solutions. Key words: Location privacy, pseudonyms, Bluetooth 1 Introduction 1.1 Wireless Personal Area Networks During the last couple of years, there is a strong tendency towards mobility for IT and computer networks. Wireless networks are rapidly gaining in im- ⋆ A preliminary version of this paper appeared in the ACM workshop on Wireless Security (WISE), 2006 [21] * Corresponding author Email addresses: Dave.Singelee@esat.kuleuven.be (Dave Singel´ ee), Bart.Preneel@esat.kuleuven.be (Bart Preneel). URLs: http://www.esat.kuleuven.be/∼dsingele (Dave Singel´ ee), http://www.esat.kuleuven.be/∼preneel (Bart Preneel).