Introducing the cloud

Before exploring the advantages of cloud computing, perhaps we should define what it is. In the pre-cloud days, if you needed computing power, you bought an actual, physical computer. But from the customer's point of view, we don't necessarily want a computer: we just want to compute. We would like to be able to buy as much or as little compute resource as we happen to need at a given time, without paying a large fixed cost for a dedicated computer.

Enter virtualization. A single physical server can provide a large number of virtual servers, each of which is (in theory) completely isolated from the others. The hosting provider builds a platform (consisting of many physical servers networked together) which provides, from the customer's point of view, a large intangible cloud of virtual compute resources (hence the term).

Automating cloud provisioning

Creating new cloud instances is cheaper and easier than buying physical hardware, but you still have choices to make: how...