Cloud computing is a term, which involves virtualization, distributed computing, networking and web-services. It is a way of offering services to users by allowing them to tap into a massive pool of shared computing resources such as servers, storage and network. User can use services by simply plug into the cloud and pay only for what he uses. All these features made a cloud computing very advantageous and demanding. But the data privacy is a key security problem in cloud computing which comprises of data integrity, data confidentiality and user privacy specific concerns.