Consider the following generic definition of the cloud that some technologists use: The cloud is a large compute resource that we can dynamically provision and make available to clients as virtualized infrastructure, which you can support with security and management controls. Although not the most exciting definition, it is correct, but here’s the interesting part. This is very similar to the description of mainframe computers back in the 1970s. It appears that we’ve come full circle.
With that in mind, let’s take a look at the six computer models that have brought us from the mainframe’s heyday in the 70s and early 80s to today’s cloud paradigm three decades later.