So what is ‘Cloud’ computing?

I’ll apologise upfront as there is lots of jargon in this post, but if you are interested in the benefits of cloud and you don’t want to be cloud-jacked it should be a useful read. It’s not all about technology and strange new terms. The cloud provides significant business benefits.

Cloud Computing Definition

The National Institute of Standards and Technology (NIST) in the USA defines cloud computing as follows:

Cloud computing is a model for enabling convenient, on-demand network access to a shared pool of configurable computing resources (e.g. networks, servers, storage, applications, and services) that can be rapidly provisioned and released with minimal management effort or cloud provider interaction.

Four Cloud Models

The differences are about scope and access:

  • Private – for a single organisation e.g. Logica private cloud.
  • Public – is accessible to the general public e.g., Google Apps, Amazon EC2.
  • Hybrid – some resources are managed in-house and others are provided externally, perhaps for information security reasons.
  • Community – the infrastructure is shared by several organisations often in a similar sector e.g. Google Apps for the US Government

Three Types

  • Infrastructure as a Service (IaaS) – virtual servers (e.g. Rackspace).
  • Platform as a Service (PaaS) – databases (e.g. Azure, Amazon RDS) and programming (e.g. Azure,
  • Software as a Service (SaaS) – applications (e.g. and numerous other examples).

Of the three types, SaaS provides the most business benefits by providing IT on Demand without the management overhead of deploying and managing infrastructure, platform and applications. It is really important to bear in mind that to get the maximum benefits you need to understand the constraints and accept that you may not get a 100% fit to your requirements. However, remember that these services are under constant development and if the market is not demanding it, you have to ask yourself whether it is really required. It’s good to apply the 80/20 rule.

Attractive Commercial Terms

The traditional approach to IT is about building solutions from the ground up (network, platform and applications). This takes a time, effort, capital investment and planning e.g. working out how many servers and how much bandwidth is required at peak times. Public SaaS solutions provide all that for you. Instead you pay based on usage, like your water bills (hence the term commodity services). This can be performance, bandwidth, storage, users i.e. you pay for what you use and you can be set up and ready to go in minutes e.g. Perhaps stating the obvious, to maximise the business benefit you have to consider how it’s going to be used and integrated with other systems and processes, but at least if it doesn’t work out you have only spent a relatively small amount and money.

I could go on and talk about some of the issues with cloud. For example, you can’t choose to sweat your IT assets, but I think this is long enough already.

What’s the difference between a virtual server and cloud?

It’s the technology on the first rung of the cloud ladder – IaaS. However, the commercials and service need to be cloud-like. On IaaS you should be able to set up a server in minutes and pay for usage. Some suppliers treat them just like normal servers ie wait for them to be setup, months, and long contracts. Plus, we use virtual servers in offices but own the physical hardware – ie two virtual servers on on physical server.

Find out more here: Cloud Computing: Concepts, Technology & Architecture (Prentice Hall Service Technology Series from Thomas Erl)

6 comments… add one

  • Mart 23/04/2013, 21:22

    What is the difference between Infrastructure as a Service (IaaS) and virtual servers from the likes of Vmware.

  • Tony Bright 23/04/2013, 21:32

    Hi Mart, thanks for the question. Infrastructure as a Service will use virtual server technology from the likes of Vmware. The difference is around how the service is set up. For example, on public IaaS platforms such as Microsoft Azure and Amazon AWS you can spin up a new server in a matter of minutes. A traditional system integrator may use Vmware to provision services but the process may take just as long as the process to provision a physical server removing many of the benefits of cloud around agility. They will often call these private clouds when they are really just virtual servers.

  • Ramadhani 28/09/2013, 16:00 have just said that the is 4 models of cloud but you gave us 3…so what’s the forth? thank you

    • Tony Bright 25/10/2013, 17:48

      Hi, that’s a formatting error the fourth is community.

  • saran 30/01/2014, 07:52

    Cloud Computing For Mobile Users: Can
    Offloading Computation Save Energy?

    • Tony Bright 12/07/2015, 09:56

      Hi, yes it can


Leave a Comment