Cloud Computing Is Environment Which Enablesconvenient, Efficient, On-Demand Network Access to a Shared Pool Ofconfigurable Computing Resources (E.G., Networks, Servers, Storage,Applications, and Services) That Can Be Rapidly Provisioned and Released Withminimal Management Effort or Service Provider Interaction. Cloud Is Kind Ofcentralized Database Where Many Organizations/Clients Store Their Data,Retrieve Data and Possibly Modify Data. Cloud Is a Model Where User Is Providedservices By Csp(Cloud Service Provider) on Pay Per Use Base. Means Here Clienthas to Pay For What He Is Using or Being Served. Data Stored and Retrieved Insuch a Way May Not Be Fully Trustworthy So Here Concept of Tpa(Third Partyauditor) Is Used. Tpa Makes Task of Client Easy By Verifying Integrity of Datastored on Behalf of Client. In Cloud, There Is Support For Data Dynamics Meansclients Can Insert, Delete or Can Update Data So There Should Be Securitymechanism Which Ensure Integrity For the Same. Here Tpa Can Not Only See Thedata But He Can Access Data or Can Modify Also So There Should Be some Securitymechanism Against This. Cloud Computing Is Thenext-Generation Architecture of Computing. It Moves the Software and Databasesto the Large Data Centers, Where the Management of the Data and Services Canface a Number of Challenges. By Outsourcing Data, Users Are Free from Theburden of Local Data Storage and Maintenance. However, Since the Users Does Nothave Physical Possession of Large Size of Outsourced Da ...