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Cloud computing - we hear the term almost daily. But really, just what is cloud computing all about? First of all, it's useful to understand where the term came from. It most likely originated from the use of a cloud image to represent a networked computing environment or the internet.
A quick Google search will reveal a number of definitions for cloud computing. I like a definition I picked up from Wikipedia which defines cloud computing as 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 utility similar to the electricity grid over a network which is most often the internet. To sort out some of the confusion around cloud computing, it is helpful to understand the various service models, of which there are three - software as a service (SaaS), platform as a service (PaaS) and infrastructure as a service (IaaS).
SaaS is the most widely known flavour of cloud service. SaaS is sometimes referred to as on demand software. With SaaS, software and its associated data are centrally hosted and are typically accessed over the internet using a browser. What are some examples of SaaS? Mailchimp, the application we use to distribute our newsletters, is an example. Zoho CRM is another example of SaaS. Gmail is another example and the list continues to expand.
PaaS provides the delivery of a computing platform and required solutions to facilitate the deployment of applications without having to invest in the cost and complexity of hardware and software. Some examples of PaaS include Microsoft Azure and Google's App Engine.
The IaaS service model allows clients to avoid the procurement of servers, software, data centre space and network equipment. Such resources are provided as a fully outsourced service. Examples of IaaS include Amazon's Elastic Compute Cloud, IBM and Rackspace.
In addition to the various cloud service models, it's useful to understand the delivery models through which cloud computing is distributed. The main delivery models include public, private, community and hybrid.
A public cloud offers infrastructure and solutions to the general public and is typically owned by a large organization that sells cloud services.
A private cloud is designed solely for one organization. A private cloud may be managed by the organization which uses it or by a third party and the infrastructure may be located on the site of the cloud user or elsewhere.
A community cloud is shared by several organizations and supports a community of users, usually with some common interest, such as regulatory concerns.
A hybrid cloud model consists of two or more clouds, for example a public and private cloud, bound together by technology to facilitate data sharing and portability.
So now that you know what cloud computing is, its service models, and how cloud computing solutions are delivered, you may be asking yourself is cloud computing an option suitable for my business requirements? I will address that question in a subsequent article. You can find out when the article will be available through my blog, Business Perspectives. 早くて便利なクラウドサービス