ICI 2 TM 2017 ISBN: 978-81-927230-0-9 221 | Sinhgad Institute of Management & Computer Application (SIMCA) Hybrid Data Encryption Technique for Data Security in Cloud Computing Basel Saleh Al-Attab Research Scholar, Yemen nationality H.No.26, Garafa , Alodain Street, Ibb City, Yemen. P.O.Box 70270 atbbael@gmail.com Dr. H. S. Fadewar Assistant Professor School of Computational Sciences, S. R. T. M. University, Nanded, India fadewar_hsf@yahoo.com Abstract—With the enormous growth in cloud computing services, data and network security are important issues in cloud computing environment. Since the cloud computing and all of its data are accessible to anyone over the insecure networks, there have been many security issues and challenges faced the cloud computing. Many of the studies try to solve these issues, but still, some of these issues remain unsolved. One of the efficient techniques to ensure data security is cryptography. This paper attempts to propose a new hybrid data encryption scheme to enhance the security and solve the data security problems such as key and security weakness, time complexity, and slow performance. Keywords— Cloud Security, Security Algorithm, CSP, Cryptography. I. INTRODUCTION Cloud computing is an emerging computing technology that uses central remote servers and internet to maintain applications and data. Its benefits include on-demand self- service, unlimited resource pooling, broad network access, fast deployment, lower costs, rapid provisioning, rapid, ubiquitous network access, greater resiliency, dynamic scalability, service-measured pricing, and alleviation of management risks [1]. With the development of cloud computing, and its benefits, cloud computing motivates users (individual, or enterprise) to outsource their data to remote servers hosted by a Cloud Server Provider (CSP). As the cloud computing resources and services are open for public use and communication is performed over the Internet, data security risks and challenges are raised under untrusted cloud environments. Confidentiality, integrity and availability (CIA) are the greatest concerns with regards to security in cloud computing [2], so maintaining CIA for data security is a function of the correct application and configuration of network, system, and application security mechanisms at various levels in the cloud computing infrastructure. The security concerns with respect to cloud computing are network traffic, end user data security, host machine security, and file systems, which cryptography can resolve to some range and thus helps organizations in their opposed acceptance of cloud computing [3]. In the cloud computing, there are various security issues such as ensuring secure data transfer, ensuring secure interface, separation of data, secure stored data, and user access control [4]. Therefore, the current study aims to propose a new data security scheme in cloud computing environment by using hybrid data security with Fig. 1 Cloud Computing Environment respect to cloud computing requirements and solve the data security issues such as mathematical complexity, key and security weakness, time complexity, complex processing on data and slow performance . This paper is organized as follows: in addition to Introduction, the security requirement in the cloud computing is presented in section II. The third section presents the data security algorithms, the literature study and existing work is presented in the fourth section. The proposed scheme and its working are explained in section V. Finally, the conclusion is presented in section VI. II. DATA SECURITY REQUIREMENTS Cloud computing provides the way to share differentiate services and resources which belong to different organizations of sites. Since cloud computing share these resources via network in the open environment thus it make security