A cloud storage system is a collection of storage servers, provides long term storage services over the web. Storing knowledge in an exceedingly third party cloud system causes serious concern over knowledge confidentiality. A secure cloud is a trustworthy source of information. Protecting the cloud is a very important task for cloud storage service providers. Now-a-days, there is the need of low-maintenance system which automates administration regularly and also need of access control over network so that data security is maintained and insured.