Every 15 years or so, the IT world undergoes a tectonic shift. Technological forces collide and grind against one another, creating an upheaval that leaves the landscape irrevocably changed. The latest such shift is currently underway: the transition to computing as a service, also known as cloud computing. This change promises to make computing more like a utility such as electricity or telephony — users plug in and get the resources they need without much manual effort on the part of service providers.
Cloud computing has brought these benefits to Internet titans like Google, Salesforce.com and Amazon, and to their customers. Traditional enterprise IT has long aspired to the same advantages, but with a crucial distinction. Businesses want the option of greater control over governance, security and management that comes with using their own infrastructure.
For the better part of the last decade, cloud computing within the enterprise appeared elusive, short of totally replacing the hardware and software infrastructure to resemble large public web sites. Then came server virtualization, pioneered by VMware in the early part of the decade. At first, virtualization’s ability to tie disparate servers into a unified pool was used only for software development and testing. But gradually, it has become apparent that the technology was mature enough to deploy more widely. Suddenly, private clouds began to appear realistic.
This report is neither a comprehensive recipe for building a private cloud nor a complete review of all the products and vendors involved. Rather, it is a roadmap outlining the technology’s likely evolution, starting with the bottom layer in Figure 1. Readers familiar with cloud computing concepts at the infrastructure level will find the parts of the report that review lower layers of the IT stack somewhat remedial. They are there to set the context for the more forward-looking sections that describe how higher-level layers are likely to evolve.