A side from the IaaS, PaaS, and SaaS lingo, which I know can be confusing to some, I want to once again explain what the cloud is from a different angle. I want you to think about what your IT organization offers you today - it is, at the end of the day, the application they provide that has the most value, right? The application is the “what” part but do not get me wrong, the “how” part of how such application is delivered to you is very important, perhaps not so much to you, the user, but more so for your IT organization and bottom line of your organizations competitive edge, your comfort and satisfaction as a user, and the overall financial and commercial viability of your business.
So, in the light of the above, you can think about the cloud from two different dimensions:
- “Ready to go/Finished products” IT services in the form of “applications” that are designed for specific purpose. In the intro above, it was the application that matters. So in this dimension, the “what” part is made available, consumed, and it is business as usual. The corporate email application you are consuming today is a form of such service because almost everyone out there uses email and such application (Exchange online, in this example) is provided as a standard service. The “how” part is different in this cloud dimension because your IT organization does not have to worry much about this application. In fact, the IT administrators would use and consume the application they way you do, as an end user.
- “Not so ready to go/not so finished products” IT services in the form of platform. Not every business application is a commodity and therefore such not-commodity software cannot be made available as finished products and be commercially viable. This cloud dimension gives you all the “plumbing” you need for your custom application so that you only have to focus on the application. So, you still have to build the application while the platform will provide the networking, the storage, the compute, the OS, the run time, the load balancer, the database, and everything that ties it all together. An example that comes to mind: You want to have a Windows PC. The hardware manufacturer whether it is HP, Dell, Lenovo, or whoever provides the platform but the platform alone is not of much value. Microsoft builds the Windows OS and does NOT worry at all or not much about the hardware manufacturing process and intricacies.
The above are the two encompassing dimensions to the cloud but you might ask, what is all this talk about public and private clouds. Well, that is a different aspect of the cloud. Let me simply this one too: the ready to consume/build your application dimensions (as outlined in #1 and #2 above) are all available on the public cloud today. In the public cloud model, you consume the finished application and “someone else” worries about everything else; or you build the application for consumption and “someone else” worries about making the platform available for you to build on. In the private cloud model, the same rules apply but with one exception: The “someone else” is in fact you. I will let you do the math.
There are typically very good and legitimate reasons for building the case for private and public cloud or even use some of each. Having choices is a good thing J
More on the topic at http://www.microsoft.com/cloud