iPDA: Privacy-Preserving Location-based Data Access in Mobile Environments*


Recent advances in wireless communications and location positioning technologies have made possible the provision of location based services (LBS) to mobile users. With a location-aware wireless device, a mobile user is able to query his/her surroundings (e.g., finding the nearest gas station or all shopping centers within 5 miles) at any place, anytime. While this ubiquitous computing paradigm brings great convenience for information access, it raises a concern of potential intrusion of user's location privacy, which has hampered the widespread use of LBS. This proposed project attempts to support location-based data access with protection of location privacy. We propose a novel client-based framework for answering privacypreserving location-based queries based on a location cloaking technique. We identify the key issues arising in the proposed framework and study the location cloaking, query evaluation, and result refinement algorithms for various locationbased queries. Furthermore, we propose a privacy-preserving caching scheme that naturally fits into the proposed framework in order to improve data access efficiency. In contrast to conventional caching schemes that only cache a portion of dataset, the proposed caching scheme maintains a global view of the whole dataset, which facilitates local processing of location-based qeuries and achieves privacy protection. Various cache design issues including space management, replacement, and consistency will be investigated in this project.

[Relevant Publications]

  1. H. Hu, J. Xu, S. T. On, J. Du, and J. K. Ng. "Privacy-Aware Location Data Publishing." ACM Transactions on Database Systems (TODS), 35(3), July 2010. [pdf]
  2. H. Hu and J. Xu. "2PASS: Bandwidth-Optimized Location Cloaking for Anonymous Location-Based Services." IEEE Transactions on Parallel and Distributed Systems (TPDS), 21(10): 1458-1472, October 2010. [pdf]
  3. H. Hu, J. Xu, and D. L. Lee. "PAM: An Efficient and Privacy-Aware Monitoring Framework for Continuously Moving Objects." IEEE Transactions on Knowledge and Data Engineering (TKDE), 22(3): 404-419, March 2010. [pdf]
  4. J. Xu, X. Tang, H. Hu, and J. Du. "Privacy-Conscious Location-Based Queries in Mobile Environments." IEEE Transactions on Parallel and Distributed Systems (TPDS), 21(3): 313-326, March 2010. [pdf]
  5. X. Pan, X. Meng, and J. Xu. "Distortion-based Anonymity for Continuous Queries in Location-Based Mobile Serv ices." Proc. the 17th ACM SIGSPATIAL Int'l Conference on Advances in Geographic Info rmation Systems (ACM GIS '09), Seattle, USA, November 2009. [pdf]
  6. H. Hu and J. Xu. "Non-Exposure Location Anonymity." Proc. IEEE 25th International Conference on Data Engineering (ICDE '09), Shanghai, China, March 2009. [pdf]
  7. X. Pan, J. Xu, and X. Meng. "Protecting Location Privacy against Location-dependent Attack in Mobile Services." Proc. ACM 17th Conference on Information and Knowledge Management (CIKM '08), Napa Valley, CA, USA, October 2008. (poster paper) [pdf]
  8. J. Du, J. Xu, X. Tang, and H. Hu. "iPDA: Supporting Privacy-Preserving Location-Based Mobile Services." Proc. the 8th Int. Conf. on Mobile Data Management (MDM '07), Mannheim, Germany, May 2007. (Demo) [pdf]
  9. Z. Xiao, X. Meng, and J. Xu. "Quality-Aware Privacy Protection for Location-Based Services." Proc. the 12th Int. Conf. on Database Systems for Advanced Applications (DASFAA '07), Bangkok, Thailand, April 2007. [pdf]
  10. C. K. Lee, W.-C. Lee, B. Zheng, and J. Xu. "Caching Complementary Space for Location-Based Services." Proc. the 10th International Conference on Extending Database Technology (EDBT '06), Munich, Germany, March 2006. [pdf]

* This project is supported by the Research Grants Council (RGC), Hong Kong SAR, China under Project No. HKBU211206. For further information, please contact Jianliang Xu.