The concept of Cloud Computing is often likened to an electricity grid where shared resources information and software are provided to Internet users as they require it. This innovation is a significant shift from the conventional mainframe system which serviced the the client server found in the nineteen eighties. Clients do not require any expertise in technology infrastructure or the need for such a service.
This term describes anything that involves delivery of a hosted service over the Internet. The hosted services are then divided into 3 broad sectors, which are Software-as-a-Service (SaaS), Platform-as-a-Service (PaaS) and Infrastructure-as-a-service (IaaS) . The Web is represented as a cloud of diagrams and software and that is where the name derives from.
The three distinctive characteristics, which set apart this kind of hosting from the type hosting of old is that, they are usually sold in time periods and are flexible. The users can decide how much or how little they require and it will be made available usually instantly. These services are fully managed by the service providers. The only requirement one needs as a client is a computer and access to the Internet.
This concept has been accelerated by better infrastructure and availability of broadband Internet, weaker economy and drastic innovation in the field of virtualization and distributed computing. These services are furthermore private or public. A public service usually provides Internet services to the public and private services are proprietary data centers or networks, which supply hosted services to individuals.
Service providers create private clouds using public resources and also create VPN (virtual private network clouds). The main goal is to provide measurable, simple access to computing resources and information technology services, whether public or private.
IaaS services provide virtual server instances and blocks of storage as clients demand them. Application Program Interface (API) is used by customers to access, discontinue and configure virtual servers and storage. Clients then only pay for the amount of capacity they need and access them quickly when needed. It is also sometimes called utility computation, as it closely resembles the manner in which we pay for water, electricity and fuel.
Developers are able to design systems on the providers platform over the Web. This is commonly referred to as PaaS (Platform-as-a-Service). APIs, gateway software or web portals are installed on the client computer and the service is provided to the end user, which enables them access to the system. This is just a drop in the bucket when it comes to the possibilities of Cloud Computing.
