Author(s): Annet Sahila G
—Social networking makes digital communication technologies sharpening tools for extending the social circle of people. Privacy preservation is a significant research issue in social networking.Here user profile matching with privacypreservation in mobile social networks (MSNs) is studied and a family of profile matching protocols is introduced. An explicit Comparison-based Profile Matching protocol (eCPM) which runs between two parties, an initiator and a responder is proposed which enables the initiator to obtain the comparison-based matching result about a specified attribute in their profiles, while preventing their attribute values from disclosure.An implicit Comparison-based Profile Matching protocol (iCPM) is then proposed which allows the initiator to directly obtain some messages instead of the comparison result from the responder. The messages unrelated to user profile can be divided into multiple categories by the responder. The initiator implicitly chooses the interested category which is unknown to the responder. Two messages in each category are prepared by the responder, and only one message can be obtained by the initiator according to the comparison result on a single attribute. iCPM is further generalized into an implicit Predicate-based Profile Matching protocol (iPPM) which allows complex comparison criteria spanning multiple attributes.