JCC_V1_N1_RevP1 C. Sasikala C. Shoba Bindu Journal on Cloud Computing 2350-1308 1 1 26 32 Cloud Computing, Data Integrity, Proof of Retrievability, PDP and HAIL Cloud Storage also known as data storage as a service, is one of the most popular cloud computing services. It allows the clients to release their burden of storing and maintaining the data locally by storing it over the cloud. Cloud storage moves the client's data to large data centers, which are remotely located, on which user does not have any control. If multiple providers cooperatively work together, the availability of resources can be increased. But still clients worry that whether their data is correctly stored and maintained by the cloud providers without intact. Hence, there is need of checking the data periodically for correction purpose which is called data integrity .In this paper we will discuss data integrity techniques that has been proposed so far, along with their pros and cons, like Proof of Retrievability (PoR), Provable Data Possession ( PDP) and a High Availability and Integrity Layer for cloud storage(HAIL). November 2013 - January 2014 Copyright © 2014 i-manager publications. All rights reserved. i-manager Publications http://www.imanagerpublications.com/Article.aspx?ArticleId=2802