Understanding IAAS (Infrastructure as a Service) Computing

Information technology can sometimes be a real alphabet soup. Cloud computing is no exception with its cryptic acronyms such as IaaS, PaaS and SaaS. Let’s look at IaaS in more detail, as this service corresponds to much of the online data and file storage done today. We’ll also look briefly at its companion services, PaaS and SaaS, to see how the three together form the basis of most of the cloud computing done today.
understanding iaasWhat is IAAS Computing?
IaaS or the ‘Infrastructure as a Service’ refers to the basic online computing resources such as processing power, storage space and network connectivity. Access to these resources is typically made available to customers via the Internet. The service provider may make an individual physical machine available to a customer, for instance for enhanced security. Often however, the resource offered is a virtual machine, with several virtual systems (meaning several customers) sharing the same physical machine. It is the service provider that controls and manages these infrastructure computing resources. On the other hand, the customer using IaaS can choose which operating system and applications will be installed.
How IAAS Fits in to Cloud Computing as a Whole
IaaS is the lowest level of a three-level cloud computing model. The middle level is PaaS (Platform as a Service) and the highest level is SaaS (Software as a Service). As you move from one level up to another, more and more of the computing resources are pre-defined, and the use that you make of the resources becomes more and more specific. Thus, PaaS includes items like a specific operating system, database server and software development tools. With SaaS, you would be using a specific application online, such as sales automation or customer relationship management.
Online Elasticity
By making core IT resources such as data storage available as a service, IaaS computing allows customers considerable flexibility. Instead of permanently paying for maximum capacity as they would if they bought all the equipment themselves, customers can use a ‘pay as you go’ style of purchasing. Processor power, storage space and network connectivity can be modified by the customer virtually at any time. This makes it easier and more economical for the customer to handle fluctuations in computing resource requirements: for example, increasing them when opening a new factory or launching a new product, or decreasing them when merging two business groups.
IaaS is Also about Sharing
At the heart of these IaaS advantages for customers is the notion of the shared machine. Resources on one physical server in the cloud may be portioned out or reassigned as the different customer requirements change. A larger resource requirement may go the other way, with one virtual system spread over several physical machines in order to accumulate the total necessary power and storage space. IaaS providers like Amazon, Google and Rackspace have very large overall IaaS resources to offer with advanced service management and billing systems. Individual customers can virtually scale up or scale down the amount of IaaS they use without any limitations.
Who Can Benefit from IAAS?                                                                                                                                                    
IaaS benefits can be multiple and therefore appeal to different customers. From a financial standpoint, prospective customers may be entities that do not have the necessary capital to spend on their own servers; or that prefer to conserve that capital for other projects. Enterprises with strongly fluctuating computing resource requirements are also likely to see the advantage in the elasticity of offerings from IaaS providers. And thanks to the technical robustness that is typical of cloud computing providers, IaaS can also make a good base for secure backup of data and effective disaster recovery in case a customer is the victim of a mishap to its own local IT systems.