What is cloud computing


The interesting thing about cloud computing is that we’ve redefined cloud computing to include everything that we already do. I can’t think of anything that isn’t cloud computing with all of these announcements. The computer industry is the only industry that is more fashion-driven than women’s fashion. Maybe I’m an idiot, but I have no idea what anyone is talking about. What is it? It’s complete gibberish. It’s insane. When is this idiocy going to stop?

Larry Ellison, CEO, Oracle, September 2008

Even in the IT industry there is no consensus on what ‘cloud computing’ actually means, and some industry  heavyweights and critics consider the term meaningless and have been vehemently opposed to its use. Despite these objections the term has become widely adopted and even Larry Ellison went on to say: ‘We’ll make cloud computing announcements. I’m not going to fight this thing. But I don’t understand what we would do differently in the light of cloud’ (Farber, 2008).

But in many ways the meaninglessness of the term ‘cloud computing’ is itself meaningful. We can wrap up the technical concepts of this kind of computing into a nice fluffy ‘cloud’, which somehow makes it less scary and more appealing. The internet itself has traditionally been depicted as a cloud in network diagrams, and, just like the internet, business users do not need to know how it works, they just need to understand what they can do with it.

In this chapter I will present a simple three-layer model of computing in general before defining and describing cloud computing in light of this model. I will then work through a list of common adoption scenarios and compare cloud-based IT solutions with non-cloud solutions to illustrate the differences. As we shall see, there is more to cloud computing than clever technology; to IT buyers it represents a radically different way of procuring a full range of IT capabilities on a pay-per-use basis.