The buzz and excitement around cloud computing has been steadily building over the last year. There is general agreement that something big and profound is going on out there, although we may not be totally sure what it is yet. "There is a clear consensus that there is no real consensus on what cloud computing is," was one of the key conclusions at a recent conference on the subject.
I believe that one of the major reasons for both the excitement and lack of consensus is that we are basically seeing the emergence of a new model of computing in the IT world. For the IT industry, a new computing model is a very big deal. In the fifty years or so since there as been an IT industry, this would be only the third such model, centralized and client-server computing being the two previous ones.
What characterizes a computing model? There is no single dimension around which to define a computing model, which I believe accounts for the variety of definitions of cloud computing. It’s like the fable of the blind men and the elephant. Each one touches a different part of the elephant. They then compare notes on what they felt, and learn that they are in complete disagreement.