Abstract: Today security is a main issue for protecting private information.Various context-aware applications provide personalized services which collect userís contexts through sensor-equipped devices to users. Because of shortage of a secure framework in networks has moved them to appropriate goals for different risks. As privacy is susceptible nature of real-time locality context of to users, many locality sharing applications use their strategies for gathering of private context. Adversary can misuse userís context so there are various privacy preserving techniques which are used to protect userís context. If the present location related data isprivatethen userís current location information kept secret. Privacy preserving approaches for location based data are used to hide userís location related information from adversary.

Keywords: Privacy, Security, Protection, Sensitive context.