www.ijoscience.com Volume II, Issue IX December 2016 1 A Study for Authentication and Integrity of Data Files in Cloud Computing Ms. Priyanka Kumari Prof. Raj Kumar Paul M.Tech. Scholar Assisant Professor Vedica Institute of Technology Vedica Institute of Technology EmailId: priyanka3392@gmail.com EmailId: rajkumar.rkp@gmail.com ABSTRACT With the development of cloud computing, a large number of individuals and companies transfer their data and business to cloud computing. But the management of the data and services of the cloud may not be fully trustworthy. How to ensure the integrity of data stored in cloud attracts more and more attention. A number of data files authentication and integrity schemes have been conducted to recognize any modification in the exchange of data files between two entities within a cloud environment. Existing solutions are based on combining key-based hash function with traditional factors (steganography, smart-card, timestamp). However, none of the proposed schemes appear to be sufficiently designed as a secure scheme to prevent from attacks. In recent years, lots of efficient and secure solutions to ensure the outsourced data integrity are proposed. This paper provides a survey of the main research results of the previous studies. Keywords: Cloud Computing, Security, Privacy, Integrity Checking, Authentication I. INTRODUCTION The “cloud computing” is continuously evolving terminology and concepts in IT enterprises. Kumaresan M. and Dr. Venkatesan G. K. D. Prasanna written in their research paper title “An Effective Scheduling Algorithm for Auditability Awareness using Cloud “ that “Cloud Computing is an emerging computing technology in which applications and information are permanently stored in remote servers on the web and cached temporarily when required by the clients. Cloud storage services have turned out to be industrially famous because of their dynamic and distributed service. To accomplish high openness in accessing the cloud data and to provide high performance, every segment of information is replicated on various globally located servers in cloud”. Cloud computing is Internet based development and use of computer technology[1]. Cloud computing describes a new supplement, consumption and delivery model for IT services based on Internet, and it typically involves the provision of dynamically scalable [2] and often