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Many consider cloud computing to be an unusually dramatic leap forward, even a paradigm shift. Cloud represents an amalgam and evolution of existing technologies taken in support of new business models and with a greater scope of users and uses.
At the most basic level, cloud technologies provide users with access to computing infrastructure, platforms (operating systems, development environments, etc.), and software applications via a network (generally the web)
Cloud computing holds promise in multiple segments from cloud products for Web content management to using cloud-based applications for natural language search and analytics.It is a model for enabling ubiquitous, on-demand access to a shared pool of configurable computing resources (e.g., computer networks, servers, storage, applications and services) which can be rapidly provisioned and released with minimal management effort.
cloud computing allows companies to avoid up-front infrastructure costs (e.g., purchasing servers). As well, it enables organizations to focus on their core businesses instead of spending time and money on computer infrastructure.
Cloud computing is a short label, but it describes a vast array of business models, technologies and services. At the simplest level, cloud computing enables IT capabilities to be delivered as a service to users via the Internet.2 Cloud services are frequently divided into three categories – “IaaS”, “PaaS” and “SaaS.”, although this should not be taken as a finite categorization.
Infrastructure as a Service (IaaS). These services typically provide users with virtual infrastructure, such as a platform virtualisation environment and ancillary storage and networking functions. Such services can be paid for on an “as used” basis, similar to other utilities such as water or electricity.
Platform as a Service (PaaS). This category of cloud computing sits between IaaS and SaaS. Cloud platforms include not only virtual infrastructure but also cloud application environments (and applications). Users can operate PaaS services to create and operate bespoke applications.
Software as a Service (SaaS). These services offer users access to software programs without the need to locally install and run the software. This reduces the need for each user to have their own high level computing capabilities and often also reduces maintenance costs.