|Project Description: ||In this research, privacy preservation with user profile matching in mobile social networks (MSN’s) is studied by introducing a family of novel profile matching protocols. An explicit comparison based profile matching protocol (ecpm) is been proposed first which runs between two parties an initiator and a responder. The ecpm prevents the attribute values from disclosure by enabling the initiator to obtain the comparison based matching result about a specified attribute in their profiles . The second protocol is the comparison-based profile matching protocol which works by allowing the initiator to directly obtain some messages instead of comparing result from the responder. The above two protocols achieve the confidentiality of user profiles based on the anonymity analysis. Offensive decoy technology is proposed which is used for securing monitoring and detecting abnormal data access patterns. This technology protects against the misuse of real data by launching a disinformation attack returning large amounts of decoy information to the attacker. Experiments conducted in a local file setting provide evidence that this approach may provide unprecedented levels of user data security in a cloud environment.