This paper explains the basic concept of cloud computing, its key characteristics and process of evolution. The various layers such as platforms, applications, infrastructures and clients which utilize the services of cloud computing; deployment models comprising of public cloud, private cloud and hybrid cloud; architecture involved in the delivery of the cloud computing and sustainability, private, legal and security issues, compliance, open source and the major fields where cloud computing finds its applications are described.
1. Definition of Cloud computing
Cloud computing is a technology that uses the Internet and central remote servers to maintain data and applications. It is the delivery of computing as a service rather than a product, whereby shared resources, software, and information are provided to computers and other devices as a metered service over a network. Cloud computing is a marketing term for technologies that provide computation, data access, software and storage devices that do not require end-user knowledge of the physical location and configuration of the system that delivers the services. Cloud computing is a model for delivering information technology services in which resources are retrieved from the internet through web-based tools and applications, rather than a direct connection to a server. Data and software packages are stored in servers. However, cloud computing structure allows access to information as long as an electronic device has access to the web. This type of system allows employees to work-remotely. Cloud computing is a marketing term for technologies that provide computation, software, data access, and storage services that do not require end-user knowledge of the physical location and configuration of the system that delivers the services. A parallel to this concept can be drawn with the electricity grid, wherein end-users consume power without needing to understand the component devices or infrastructure required to provide the service. It is delivery model for IT services based on Internet protocols, and it typically involves provisioning of dynamically scalable and often virtualized resources. Cloud computing providers deliver applications via the internet, which are accessed from web browsers and desktop and mobile apps, while the business software and data are stored on servers at a remote location. In some cases, legacy applications are delivered via a screen-sharing technology, while the computing resources are consolidated at a remote data centre location; in other cases, entire business applications have been coded using web-based technologies such as AJAX.. It is delivery model for IT services based on Internet protocols, and it typically involves provisioning of dynamically scalable and often virtualized resources. Cloud computing is a byproduct and consequence of the ease-of-access to remote computing sites provided by the Internet. This may take the form of web-based tools or applications that users can access and use through a web browser as if the programs were installed locally on their own computers. This is based on the concept of infrastructure convergence and shared services. This type of data centre environment allows enterprises to get their applications up and running faster, with easier manageability and less maintenance, and enables IT to more rapidly adjust IT resources to meet fluctuating and unpredictable business demand. Investopedia explains that Cloud computing is so named because the information being accessed is found in the “clouds”, and does not require a user to be in a specific place to gain access to it. Companies may find that cloud computing allows them to reduce the cost of information management, since they are not required to own their own servers and can use capacity leased from third parties. Additionally, the cloud-like...