Many mobile social networking applications are based on the concept, according to which two mobile users try to jointly estimate whether they have common friends, or share same interests, etc. Performing “friend detection” in a privacy-preserving way is fundamental to achieve widespread acceptance of mobile social networking applications. What so ever, the need of privacy preservation is often at odds with application-level performance of the mobile social networking application, since only profuse information about the other user’s profile is available for optimizing performance, More specifically, it is considered a mobile social networking application for opportunistic networks called interest-casting. In this model, a user wants to exchange a piece of information to other users sharing similar interests, possibly through multi-hop forwarding. It is proposed that the privacy-preserving friend proximity detection scheme based on a protocol for solving the Yao’s “Millionaire’s Problem”, and the three interest-casting protocols achieving different tradeoff between privacy and accuracy of the information forwarding process. The privacy versus accuracy adjudge is analyzed both analytical, and through simulations based on a real-world mobility trace.
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Opportunistic networks; Interest-casting; Social Networking; Privacy preservation.