The Cloud is the image for the Internet network diagram. Cloud computing is not a new technology but a new concept which merges a platform of applications. The concept runs on the Internet thereby providing applications to the users without the need of physical software or complex infrastructure.
Cloud computing refers to abstracting away physical servers, storage, and networking and instead offering these as on-demand and elastic resources. An API is typically exposed to provide programmatic control over these resources. Traditionally, without a cloud, a web server runs as a single computer or a group of privately owned computers. The computer(s) are powerful enough to serve a given amount of requests per minute and can do so with a certain amount of latency per request. If the computer's website or web application suddenly becomes more popular, and the amount of requests are far more than the web server can handle, the response time of the requested pages will be increased due to overloading. On the other hand, in times of low load much of the capacity will go unused.
Cloud computing can be classified to several viz. Infrastructure as a Service, Platform as a Service, and Software as a Service.
Cloud computing services are emerging technologies that provide both businesses and individuals many benefits such as lowered costs and ease of accessibility. But have also come with issues such as legal and security risks.
History
The name Cloud computing was inspired by the Cloud symbol that's often used to represent the Internet in flow charts and diagrams. The underlying concept of Cloud computing dates back to 1960 when John McCarthy (an American computer scientist) opined that, "computation may someday be organized as a public utility.”
An Emerging Business model
There is a high flexibility that comes with implementing infrastructure as a service. A company can increase or decrease how much space it rents on the Cloud as its utilization pattern varies. During peak periods, such as release dates, the companies can rent more bandwidth to accommodate the demand and then lower it during the low usage periods.
Recent studies conducted by IBM shows, only 3% of energy consumed by a data center is used for computation; therefore IBM has implemented energy efficient policies to successfully apply the economies of scale principle to increase server utilization and decrease energy costs by up to 40%. This is increasingly important as the energy costs continue to rise and hardware costs drop. Finally, moving the infrastructure to the Cloud allows companies to drastically downsize their IT departments and focus their resources on running their core business.
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