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arXiv · 1109.6883

A MovingObject Index for Efficient Query Processing with Peer-Wise Location Privacy

Dan Lin·Christian S. Jensen·Rui Zhang·Lu Xiao·Jiaheng Lu
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Abstract

With the growing use of location-based services, location privacy attracts increasing attention from users, industry, and the research community. While considerable effort has been devoted to inventing techniques that prevent service providers from knowing a user's exact location, relatively little attention has been paid to enabling so-called peer-wise privacy--the protection of a user's location from unauthorized peer users. This paper identifies an important efficiency problem in existing peer-privacy approaches that simply apply a filtering step to identify users that are located in a query range, but that do not want to disclose their location to the querying peer. To solve this problem, we propose a novel, privacy-policy enabled index called the PEB-tree that seamlessly integrates location proximity and policy compatibility. We propose efficient algorithms that use the PEB-tree for processing privacy-aware range and kNN queries. Extensive experiments suggest that the PEB-tree enables efficient query processing.

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Dan Lin, Christian S. Jensen, Rui Zhang, Lu Xiao, Jiaheng Lu. 2011-09-30. A MovingObject Index for Efficient Query Processing with Peer-Wise Location Privacy. https://arxiv.org/abs/1109.6883

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