1. Cloud Computing Overview:    
Cloud computing is the new model for delivering the IT services, the previous models start from the mainframes to the Server-Client approach then the Application Service Providers (ASP). Cloud computing is not a new innovation in reality it can be considered the evolution and convergence of several independent computing trends such as Internet delivery, “pay-as-you-go” utility computing, elasticity, virtualization, grid computing, distributed computing, storage, content outsourcing, security, and Web 2.0.
You already use the cloud; you just may not realize it. Cloud ubiquitous but it goes by so many names that many people do not realize that their day-to-day applications may in fact be cloud-based.
Cloud computing is all about simplicity and ease of management that the user can use an application or system without the need to worry about how the application or system works. It doesn’t automatically mean that the application or system is hosted on the internet. Cloud computing gives your users, developers, and even IT administrators access to shared applications and systems maintained by someone else.
According to a 2012 report  published jointly by the Cloud Security Alliance and the Information Systems Audit and Control Association (Cloud Computing Market Maturity: Study Results, ISACA, 2012), cloud computing is “at the point of advancing from infancy to growth and is reaching a level of maturity at which enterprises can benefit greatly by adopting cloud infrastructure, platform or software service offerings”.
The Term “cloud” first used to describe the business model of providing services across the Internet was in 2006 by Google’s CEO Eric Schmidt below is a brief history of the cloud computing:
- 1961, John McCarthy envisioned that computing facilities would be provided to the public like a utility.
- 1967, IBM (key contributor Jim Rymarczyk) launches CP-67 software; one of IBM’s first attempts at virtualizing mainframe operating systems.
- 1999, Salesforce.com introduces the concept of delivering enterprise applications via a website and Ian Foster and Carl Kesselman originate the term grid computing.
- 2002, Amazon Web Services provide a suite of cloud-based services, including storage and computation.
- 2006, Amazon launches Elastic Compute (EC2) as a commercial Web service that small companies and individuals rent to run their own computer applications.
- 2008 HP, Intel, and Yahoo! announced the creation of a global open computing laboratory, Cloud Computing Test Bed, which encompassed a variety of platforms for the development of research and technology in the field of cloud computing.
- 2010, the First International Cloud Computing Congress was held.
 Q. Zhang, C. Lu and B. Raouf , “Cloud computing: state-of-the-art and research challenges,” Journal of Internet Services and Applications, vol. 1, no. 1, pp. 7-18, 2010.
 “VMware Certified Associate – Cloud (VCA-Cloud),” [Online]. [Accessed October 2013].
 G. Pallis, “Cloud Computing The New Frontier of Internet Computing,” Internet Computing, IEEE, vol. 14, no. 5, pp. 70 – 73, 2010.
 V. V. Arutyunov, “Cloud Computing: Its History of Development, Modern State, and Future Considerations,” Scientific and Technical Information Processing, vol. 39, no. 3, pp. 173-178, 2012.
 S. Murugesan, “Cloud Computing: The New Normal?,” Computer , pp. 77-79, JANUARY 2013.