Cloud computing is a web based technology that change the users way of working and provide online collaboration. Cloud computing is user centric, task centric, powerful, accessible, intelligent and programmable. Cloud computing offers convenience, speed, provides users with on – demand services and can be accessed when required. Several benefits are offered by cloud computing but one of the barrier of cloud computing is security because data is stored on multiple third-party servers, rather than on the traditional dedicated servers which are used in traditional data storage.