A rough definition: a general term that describes anything that provides hosted services over the internet (the name actually comes from the UML symbol for the internet).  Cloud computing is divided in three major types of services: infrastructure as a service (IaaS), platform as a service (PaaS) and software as a service (SaaS).

IaaS – provides virtual servers with a unique IP address and custom hardware configuration for your application. The part that really gives it the edge is being able to upgrade your configuration as the application you are running demands it, no more investing in hardware or in lengthy upgrades. Because you use these services as you need them, like you do electricity and water, they are sometimes called utility services.

PaaS – is a set of software and product development tools hosted on the provider’s infrastructure. You design and implement your solution and give employees access through portals either installed on their computer or web-based. There are some risks involved, mainly because some providers will not allow you to move the application when and if you should choose to stop using their services.

SaaS – the vendor provides the hardware infrastructure and the software, both accessed through a front-end portal. The service can be anything from email inventory to data processing and can be used from anywhere as long as you have access to a web connected device. You can customize the software by sending a request to the vendor but take into consideration that this will surely reflect on your bill.

There are two types of clouds: private and public. The public cloud gives access to any number of users on the Internet. A private cloud is a proprietary network that supplies the services to a limited number of people usually using virtualization technology (virtual private cloud). The later is the choice for companies that want to customize their application and keep their data in a safer environment.

What makes cloud computing the bees knees? Well for starters you pay for the service on-demand. That means that if you use it for 1 minute, you pay one minute and if you use it for 5 hours, you pay for 5 hours worth of service. It is elastic, the user can have as much or as little service as needed, also you benefit from upgrades without it affecting your bill at the end of the day. The final and third clue you are going to use a genuine cloud and not just a label is that the services are fully supported and maintained by the provider.

Taking into consideration all of the above Cloud Computing seems to be the catalyst for a Business-IT revolution so why haven’t all the big players joined in on the cause? Stay tuned to see why are CIO’s apprehensive about migrating to cloud based solutions.

You can find below my sources of inspiration for this article:

http://searchcloudcomputing.techtarget.com/sDefinition/0,,sid201_gci1287881,00.html

http://www.jasonslater.co.uk/2010/02/27/what-is-cloud-computing/

http://www.infoworld.com/d/cloud-computing/what-cloud-computing-really-means-031?page=0,1