Efficient Oblivious Augmented Maps: Location-Based Services with a Payment Broker

  • Markulf Kohlweiss
  • Sebastian Faust
  • Lothar Fritsch
  • Bartek Gedrojc
  • Bart Preneel
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4776)


Secure processing of location data in location-based services (LBS) can be implemented with cryptographic protocols. We propose a protocol based on oblivious transfer and homomorphic encryption. Its properties are the avoidance of personal information on the services side, and a fair revenue distribution scheme. We discuss this in contrast to other LBS solutions that seek to anonymize information as well as possible towards the services. For this purpose, we introduce a proxy party. The proxy interacts with multiple services and collects money from subscribing users. Later on, the proxy distributes the collected payment to the services based on the number of subscriptions to each service. Neither the proxy nor the services learn the exact relation between users and the services they are subscribed to.


Blind Signature Location Privacy Homomorphic Encryption Oblivious Transfer Privacy Trustee 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2007

Authors and Affiliations

  • Markulf Kohlweiss
    • 1
  • Sebastian Faust
    • 1
  • Lothar Fritsch
    • 2
  • Bartek Gedrojc
    • 3
  • Bart Preneel
    • 1
  1. 1.K.U. Leuven ESAT/COSIC, Kasteelpark Arenberg 10, 3001 LeuvenBelgium
  2. 2.Johann Wolfgang Goethe-Universität, 60054 Frankfurt am MainGermany
  3. 3.TU Delf ICT, Mekelweg 4, 2628 CD DelftThe Netherlands

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