Article in Proceedings INPROC-2012-06

BibliographyWernke, Marius; Dürr, Frank; Rothermel, Kurt: PShare: Position Sharing for Location Privacy based on Multi-Secret Sharing.
In: Proceedings of the 10th IEEE International Conference on Pervasive Computing and Communications (PerCom 2012).
University of Stuttgart, Faculty of Computer Science, Electrical Engineering, and Information Technology.
pp. 153-161, english.
Lugano, Switzerland: IEEE Computer Society, March 19, 2012.
Article in Proceedings (Conference Paper).
CR-SchemaC.2.4 (Distributed Systems)
H.3.5 (Online Information Services)
KeywordsLocation-based applications; privacy; position sharing; location management

Location-based applications such as Facebook Places, Foursquare, or Loopt attract millions of users by implementing point of interest finders, friend finders, geosocial networking, etc. Typically, these applications act as clients to a location service such as Google Latitude or Yahoo Fire Eagle, which manage mobile object positions and ensure the scalability to provide various clients with mobile object positions.

However, exposing precise user positions raises user privacy concerns, especially if location service providers are not fully trusted, and private position information could be lost, leaked, stolen, etc. To enable the secure management of private user positions on non-trusted location servers (LSs), we present novel position sharing approaches based on the concept of multi-secret sharing. Our approaches split up a precise user position into position shares, which are distributed to different LSs of different providers such that a compromised provider only reveals user positions with degraded precision. On the other hand, clients can combine several shares queried from different LSs to increase their provided precision without the need to store precise information at a single LS.

We propose two position sharing approaches: PShare-SLM is the first position sharing approach presented so far for symbolic location models. For geometric location models, we present PShare-GLM, which improves existing geometric position sharing approaches[DSR11] by considering continuous position updates and by increasing the robustness against various attacks.

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Department(s)University of Stuttgart, Institute of Parallel and Distributed Systems, Distributed Systems
Entry dateFebruary 8, 2012
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