Cloud computing is now a very common term among IT peoples. In cloud computing all the computing services like servers, networking devices, application is available over the Internet. Many people can share and access different application and resources as per their need and privileges of access & authorities. In cloud computing security & privacy of data is most important point which required lot of attention by the cloud service provider. Authentication is the main concern in existing security solutions, but neglect a subtle privacy issue during a user challenging the cloud server to request other users for data sharing. User’s privacy is reveal by the challenged access request no matter it obtain the access permission or not. Ambition of this paper is to investigate and estimate the most important security techniques for data sheltering in cloud computing. We have proposed a Privacy Preserving Authentication Protocol based on Shared Authority (PPSA). Share access authority is achieved by the anonymous access request and analyzing and observing privacy. Data security is enhanced by using attribute base control system, which allows users to access their own data. To provide the data accessing from the other trusted party and sharing among the multiple users proxy re-encryption scheme is used by the cloud server. It indicates that the proposed scenario is possibly applied for enhanced privacy- preservation and security in cloud applications. We have done the review study on this scenario. In this paper we will focused on implementation of this review with assuring an improved result.

ECDH, SHA512, Authentication protocols, Cloud computing, Cloud computing security, Data security

[1]. Hong Liu, Huansheng Ning, Qingxu Xiong and Lairence T. Yang,” Shared Authority Based Privacy-Preserving Authentication protocol in Cloud Computing” IEEE Transactions on Parallel and Distributed Systems ( Volume: 26, Issue: 1, Jan. 2015 )
[2]. Antonis Michalas, “Sharing in the Rain: Secure and Efficient Data Sharing” for the cloud” 11th International Conference or Internet Technology and Secured Transaction(ICITST)2016.
[3]. 3.Ghassan O. Karame, Claudio soriente, Krzysztof Lichota, Srdjan Capkun” Securing Cloud Data under Key Exposure” IEEE Transactions on Cloud Computing ( Volume: PP, Issue: 99 )Feb 2017.
[4]. 4.Jianghong Wei, Wenfen Liu, Xuexian Hu” Secure Data Sharing in Cloud Computing Using Revocable-Storage Identity-Based Encryption”. IEEE Transactions on Cloud Computing ( Volume: PP, Issue: 99 )March 2016
[5]. 5. Mazhar Ali, Saif U. R. Malik, Samee U. Khan” DaSCE: Data Security for Cloud Environment with Semi-Trusted Third Party” IEEE Transactions on Cloud Computing ( Volume: 5, Issue: 4,)June 2015.
[6]. 6. P. Vidhya L Lakshmi, Dr. S. Sankar Ganesh, usi“A secure cloud storage system with data forwarding ng proxy re-encryption scheme”, international journal for trends in engg and tech , April 2015.
[7]. 7. Apurva Gomase, Prof.Vikrant Chole, ”Secure system implementation using attribute based encryption”, ijates,Vol.No.03,Special issue No.01,Nov 2015.
[8]. 8. Jingwei Li, dan Lin, Anna Cinzia Suicciarini, Jin Li, Chunfu Jia” Towards Privacy-Preserving Storage and Retrieval in Multiple Clouds” IEEE Transactions on Cloud Computing ( Volume: 5, Issue: 3, July-Sept. 1 2017 )October 2015.
[9]. 9. ] Deyanchen, hongzhao, ”Data security and privacy protection issue in cloud computing”IEEE conference of computer science and electronics engg, 2013.

[10]. 10.Farheen Quazi & Prof. Vikrant Chole “Implementation on Proxy-re-encryption based security mechanism to authenticate shared access in cloud computing" International Journal of Scholarly Research (IJSR) Vol-1, Issue-2, 2017

[11]. 11. Archana Singh Parmar, Monika Sharma,”Improving Data Storage Security in Cloud Computing using Elliptic Curve” International Journal of Engineering Science and Computing(Vol -7,Issue- 4)April 2017.
[12]. 12. . Shweta Singh, Tabrez Nafis, Ankita Sethi,”Cloud Computing: Security Issues & Solution”International Journal of Computational Intelligence Research (Volume 13, Number 6, 2017).
[13]. 13. Balamurugan Balusamy, P. Venkata Krishna, G. S. Tamizh Arasi, and Victor Chang,” A Secured Access Control Technique for Cloud Computing Environment Using Attribute Based Hierarchical Structure and Token Granting System” International Journal of Network Security (Vol.19, No.4, PP.559-572, July 2017)
[14]. 14. Mohamed Ali Hamza, Jianfei Sun, Xuyun Nie, Zhiquan Qin, and Hu Xiong,” Revocable ABE with Bounded Ciphertext in Cloud Computing” International Journal of Network Security(Vol.19, issue:6)Nov 2017.
[15]. 15. Prabhleen Kaur Soul, Sunil Saini,”data security approach in cloud computing using SHA”international research journal of engineering and technology(Vol:4, Issue:6)June2017.
[16]. 16. P K Akulwar, R. V. Dharmadhikari, S. S. Turambekar, S. C. Dolli “Cloud Computing: Data Storage Protocols and Security Techniques” International Journal of Scientific Research in Computer Science and Engineering Volume: 6, Issue: 2, 2018