Presentation 2004-07-20
An Assessment of Wireless Location Privacy Risks in High Precision Positioning System
Leping Huang, Kaoru Sezaki,
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Abstract(in English) The advance of ISM-band radio-based tracking systems (for example, wireless LAN-based tracking system) extends the application of location-based services (LBS), but it also threatens to allow the movement of users to be tracked whenever they are transmitting frames. Several protection methods based on periodical address updates have already been proposed. In this paper, we first evaluate the privacy risks in wireless communication, and especially in wireless LAN network. Through our analysis, we identified that new correlation attacks can defeat current periodical address updated based protection method when the accuracy of positioning system is high. Correlation attack is defined as methods, which utilize the correlation between the old and new addresses of the same node in location tracking. To combat such attacks, we propose the concept of a silent period. A silent period is defined as a transition period between the use of new and old pseudonyms, when a node is not allowed to disclose either the old or the new address. Through analysis, we find that a silent period should contain a constant period and a variable period. The effect of the constant period is to mix the spatial relation between the node's disappearing points and emerging points. The variable period mixes the temporal relation between the node's disappearing times and emerging times. We further propose a general framework to measure the location privacy, which takes into account the probabilities that users contribute to each other's privacy level, and we show how to use this framework to calculate the location privacy for a wireless system. Based on this framework, we propose two measures, called the geographical anonymity set (GAS) and the tracking accuracy (TA). Finally, we conclude with a plan for future work.
Keyword(in Japanese) (See Japanese page)
Keyword(in English) Location privacy / privacy / positioning / anonymous communication / wireless LAN
Paper # ISEC2004-28
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Conference Information
Committee ISEC
Conference Date 2004/7/13(1days)
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Registration To Information Security (ISEC)
Language ENG
Title (in Japanese) (See Japanese page)
Sub Title (in Japanese) (See Japanese page)
Title (in English) An Assessment of Wireless Location Privacy Risks in High Precision Positioning System
Sub Title (in English)
Keyword(1) Location privacy
Keyword(2) privacy
Keyword(3) positioning
Keyword(4) anonymous communication
Keyword(5) wireless LAN
1st Author's Name Leping Huang
1st Author's Affiliation Arco Tower()
2nd Author's Name Kaoru Sezaki
2nd Author's Affiliation The University of Tokyo
Date 2004-07-20
Paper # ISEC2004-28
Volume (vol) vol.104
Number (no) 199
Page pp.pp.-
#Pages 7
Date of Issue