Untraceability and Profiling Are Not Mutually Exclusive
S. Canard and A. Jambert

In this paper, we study the concept of privacy-preserving multi-service subscription systems. With such system, service providers can propose to their customers, by the way of a subscription, several distinct services that users can access while being anonymous. We more-over study how users can be untraceable w.r.t. the service provider during the subscription process, in such a way that it is additionally possible to make profiling on the users’ customs. This permits the service provider to propose some advertisements to users while protecting the privacy of the latter, even this may be seen as contradictory. We also propose concrete instantiations, based on signature schemes with extensions from Camenisch and Lysyanskaya.