Dediserve Blog

Essential Characteristics of the Cloud Computing Model

Written by Aidan | 29 March

There is much hype and confusion about cloud. What is it, what defines it? Providers try to confuse you that shared hosting or legacy style VPS servers are ‘cloud’ or worse still, dedicated servers are cloud!

Here is the ‘official’ definition:

The five characteristics of the cloud computing model were originally defined by the National Institute of Standards and Technologies (NIST) and have since been refined by a number of experts. The model has been published many times before, but if you’re like me you need to see something several times before you really internalise it.

Frankly, I recommend that you memorise this list; you’ll have the vague term “cloud” thrown at you many times in the future, and understanding these five characteristics will help you judge whether the latest offering you’re being shown is really cloud computing. And as an added plus, you’ll be able to finally explain cloud computing to your friends and relatives.

1. On-demand self-service. You can quickly and easily configure the computing resources you need all by yourself, without filling out forms or emailing the service provider. An important point is that what you’re using is service-based (“I need 15 computing units”), not resource-based (“I need an HP ProLiant DL380 G6 with 32GB of RAM”). Your computing needs are abstracted from what you’re really being allocated. You don’t know, and in most cases you shouldn’t care. This is one of the biggest hurdles for IT departments that want to create their own internal cloud computing environment.

2. Broad network access. You can access these resources from anywhere you can access the Internet, and you can access them from a browser, from a desktop with applications designed to work with them, or from a mobile device. One of the most popular application models (such as iPhone apps) is a mobile application that communicates with a cloud-based back end.

3. Resource pooling. The cloud service provider, whether it’s Dediserve or your own IT department, manages all of its cloud’s physical resources; creates a pool of virtual processor, storage, and network resources; and securely allocates them between all of its customers.

4. Rapid elasticity. You can grow and shrink your capacity (processing power, storage, network) very quickly, in minutes or hours. Self-service and resource pooling are what make rapid elasticity possible. Triggered by a customer request, the service provider can automatically allocate more or less resources from the available pool.

5. Measured service. Also described as subscription-based, measured service means that the resources you’re using are metered and reported back to you. You pay for only the resources you need, so you don’t waste processing power like you do when you have to buy it on a server-by-server basis.

Dediserve nails every one of these 5 defining characteristics – does your provider?