Architecting the Cloud: Design Decisions for Cloud Computing Service Models (SaaS, PaaS, and IaaS)

Chapter 1

Why Cloud, Why Now?

There was a time when every household, town, farm, or village had its own water well. Today, shared public utilities give us access to clean water by simply turning on the tap; cloud computing works in a similar fashion. Just like water from the tap in your kitchen, cloud computing services can be turned on or off quickly as needed. Like at the water company, there is a team of dedicated professionals making sure the service provided is safe, secure, and available on a 24/7 basis. When the tap isn’t on, not only are you saving water, but you aren’t paying for resources you don’t currently need.

— Vivek Kundra, former federal CIO, U.S. government

In 2009, I was invited to the IBM Impact conference in Las Vegas as a guest blogger and analyst. Cloud computing was a vastly misunderstood term at that time, and there were very few enterprises leveraging any cloud services other than a few of the mature SaaS solutions like Salesforce.com and Concur’s expense management software. I witnessed some very intelligent senior IT people from various companies scoffing at the term cloud computing. I can still hear the lines: “We were doing this on the mainframe in the ’60s” and “There is nothing new here, this is just a fad.” At that time, my team of one developer was testing a prototype that was executing hundreds of thousands concurrent point-of-sale (POS) transactions to the cloud and back in subsecond response time on a virtual cloud server, costing us about half ...