An introduction to web applications architecture
An introduction to web applications architecture

Start this free course now. Just create an account and sign in. Enrol and complete the course for a free statement of participation or digital badge if available.

Free course

An introduction to web applications architecture

Infrastructure as a Service (IaaS)

NIST (2011) defines IaaS as:

The capability provided to the consumer is to provision processing, storage, networks, and other fundamental computing resources where the consumer is able to deploy and run arbitrary software, which can include operating systems and applications. The consumer does not manage or control the underlying cloud infrastructure but has control over operating systems, storage, and deployed applications; and possibly limited control of select networking components (e.g. host firewalls).

IaaS delivers a cloud computing infrastructure – servers, storage, network services and virtual machines – as services. Rather than purchasing these infrastructure components, clients instead purchase access to these components as services.

Using IaaS is particularly suitable for situations including:

  • new organisations without the capital to invest in hardware
  • organisations that are growing rapidly but purchasing additional hardware would be prohibitive
  • speculative development of new lines of business without the need to invest in infrastructure components.

Examples of IaaS providers include Amazon Elastic Compute Cloud (EC2) and Google Compute Engine.

Amazon Elastic Compute Cloud (EC2) forms a central part of Amazon’s cloud-computing platform, Amazon Web Services (AWS), which supports both Amazon’s retail services and cloud services.

Google Compute Engine is the IaaS component of Google Cloud Platform which is built on the global infrastructure that runs Google’s search engine, Gmail, YouTube and other services.

We have seen that cloud computing provides three service models: laaS as the underlying infrastructure; PaaS as a web application development environment; and SaaS which replaces stand-alone applications with web applications. These three service models are key to understanding how the cloud has evolved, so it is important that you appreciate the key differences between them.

Cloud computing brings with it a number of key benefits, as well as risks, that should be carefully examined by any organisation looking to move to cloud computing. It is important for organisations to understand the different aspects of cloud computing and to assess their own requirements before deciding which service models are appropriate for their unique needs. Cloud computing is a rapidly accelerating revolution within IT and is likely to become the default method of IT service delivery in the future.

TT284_1

Take your learning further

Making the decision to study can be a big step, which is why you'll want a trusted University. The Open University has 50 years’ experience delivering flexible learning and 170,000 students are studying with us right now. Take a look at all Open University courses.

If you are new to University-level study, we offer two introductory routes to our qualifications. You could either choose to start with an Access module, or a module which allows you to count your previous learning towards an Open University qualification. Read our guide on Where to take your learning next for more information.

Not ready for formal University study? Then browse over 1000 free courses on OpenLearn and sign up to our newsletter to hear about new free courses as they are released.

Every year, thousands of students decide to study with The Open University. With over 120 qualifications, we’ve got the right course for you.

Request an Open University prospectus371