Overview on Privacy-Preserving Profile-Matching Mechanisms in Mobile Social Networks in Proximity (MSNP)

Recently, mobile social networking in proximity (MSNP) has gained tremendous attentions, which refers to the social interactions among physically proximate mobile users directly through the Bluetooth/WiFi interfaces on their Smartphones or other mobile devices. MSNP applications can provide users more opportunities to discover and make new social interactions within proximity area, e.g., Airports, bars or other social spots. However, users enjoy these conveniences at the cost of their growing privacy concerns. Usually, MSNP application consists of three phases. First, two users need discover each other in the neighbor-discovery phase, Second, they need compare their personal profiles in the matching phase, usually called private matching, Last, two matching users enter the interaction phase for real information exchange. In this paper, we concentrate on the privacy mechanisms in the first and second phases. In detail, two primary approaches to solving the privacy-preserving profile-based friend matching problem, are categorized and compared, including private set intersection (PSI) and vector dot product to measures the social proximity, and then, two typical schemes from those approaches are discussed respectively. Our primary goal is to summarize and analyze characteristics, challenges and future directions of the privacy-preserving profile-matching schemes in MSNP.