Introduction

Cloud computing is the logical evolution of Information Technology (IT) in a world that is becoming more and more based on the division of work. From small family-owned stores to big corporations the trend to outsource IT is prevalent. Cloud computing brings principles that are long established in other industries to the IT. Take the transportation industry as an example. If you want to use a car you can get this functionality in a wide range of service models. From your own car that you buy and are responsible for, to cars sourced from a company-internal pool, to a rental car from one of the rent-a-car agencies, from car-sharing models, to taxis the functionality is essentially the same – a car enabling fast self-paced driving from A to B. The differentiating factor of these mobility providers is their business model to deliver functionality and the level of guaranteed quality of service. Cloud computing brings a new choice to the service models in which IT is delivered. Cloud computing is the IT equivalent of the rent-a-car model. The promise of cloud computing is to consume IT resources (be it infrastructure, middleware platforms, software, or whole business processes) when you need them in the quantity you need them

at a certain time

. While this IT delivery model is not new from a technical perspective, the fundamental change is the business model that you only pay for IT resources

when you actually use them

. Similar to the car industry this can be game-changing and can save you lots of money, speed up your time-to-market, and make your business and IT more flexible. In other cases, where you cannot embrace this business model fully, it can be complicated and more expensive than just buying the respective IT resources and maintaining them yourself.