For those of you getting into the Cloud Computing world, the established hierarchy of the cloud these days is as follows:
SaaS has been around for many years – first known as ASP (application service provider) in the 1990’s. The most famous has been Salesforce.com’s CRM/SFA application suite. In fact, any application delivered over the internet and hosted remotely can be called SaaS – including ADP’s hosted payroll services, QuickBooks online, and tens of thousands of applications from thousands of vendors.
PaaS is a relatively new phenomenon, popularized again by Salesforce.com when they opened up their platform through their force.com offerings. This allows you to use their underlying data models and constructs to write your own applications which they host.
Finally, and most excitingly, Amazon with their AWS offerings has created this new category of virtualized data center infrastructure. Remote hosting has been around forever, but Amazon has taken it way beyond this. Google’s AppEngine, Microsoft’s Azure and RackSpace’s Mosso are also IaaS offerings. And there are many more to come.
All of this reminds me of one of my favorite scenes from Shrek…