Journal of Information Security Research Kishan Lathkar, Ambulgekar H. P 6 1 2015 Cloud computing is a revolutionary new approach to how computing services are produced and consumed. It is a concept of sharing resources and giving them as essential resources. Using cloud computing resources, data, computations, and services can be shared over scalable network of nodes; these nodes may represent the datacenters, cloud users and web services. On the same note cloud storage talk about storing the data on a remote storage located at other organization’s infrastructure. The data storage is maintained and managed by the organization; the user will pay for the storage space which is used. Outsourcing data ultimately relinquishes the control of data from user and the lot of data is in control of the cloud server. The cloud server is succeeded by cloud service provider which is a different administrative entity, so ensuring the data integrity is of prime importance. This paper studies the problems of ensuring data storage correctness and proposes an effective and secure scheme to address these issues. A third party auditor (TPA) is introduced securely. Who will on behalf of users request will periodically verify the data integrity of the data stored on cloud server. There will not be any online burden on user and security of data will be maintained as the data will not be shared directly with the third party auditor. A homomorphic encryption scheme is used to encrypt the data by using Elliptic curve Digital Signature Algorithm (ECDSA) which will be shared with the TPA. ECDSA provides efficient and secure solutions for the cloud storage servers. It leads to fast computation time, reducing in processing power, save the storage and bandwidth. The results can be further extended to enable the third party auditor to do multiple auditing simultaneously