So many vendors have jumped on the cloud computing bandwagon, the phrase already risks jumping the shark. The problem is that "cloud computing" has two distinctly different meanings: The use of commercial Internet-based services, and the architecture for building and deploying such services.
InfoWorld has adopted the former definition. Last April we boiled it down to this: "Cloud computing encompasses any subscription-based or pay-per-use service that, in real time over the Internet, extends IT's existing capabilities." That includes infrastructure services (such as Amazon EC2), software as a service (à la Salesforce), and Web-based development platforms (including Force.com, Microsoft Azure, and so on).
[ For InfoWorld's complete definition of cloud computing, see "What cloud computing really means." ]
Big vendors like Dell and IBM prefer the other definition. If you need proof, enter cloudcomputing.com in your browser and you'll be redirected to the cloud computing section of Dell's Web site. There you'll discover that Dell offers consulting services to help businesses create what amounts to a grid computing architecture with "software that often spans over thousands of hardware nodes." Heck, they might even sell you some hardware, too.
IBM offers a similarly grid-like, although vaguer, definition: "Cloud computing is an emerging approach to shared infrastructure in which large pools of systems are linked together to provide IT services." (Hmm. Sounds like a network.) And make no mistake: Neither IBM nor Dell will restrict their sale of could computing wares to providers of commercial cloud services. In their view, anyone can build and run a "private cloud" for any number of applications, particularly those that require high availability and turn-on-a-dime scalability.
Unfortunately, this pitch can degenerate very quickly into promises of IT nirvana. Using a combination of virtualization, SOA, datacenter automation, and complex event processing, your entire datacenter and its applications can form one big cloud! The business side makes a monster request to support a new line of business, and all you need to do is click and drag together some composite applications and throw a few more servers on the barbie. Well have it for ya tomorrow, mate!
Fantasies of hyperautomated, self-organizing IT have been around for decades. Don't get me wrong: I see the value of many of these ideas and technologies, particularly SOA and virtualization when they're done right. But my eyes start to cross when I hear about turning IT into a "private cloud" that delivers cloud services to the business. Yeah, maybe for a few applications that need grid-like architecture, but the whole ball of wax? Tell me another one.
So where does that leave us? I think we'll stick with our definition of cloud computing -- that is, the use of commercial computing services, including software-as-a-service applications, delivered over the Internet. But I'm happy to talk about the architecture and technologies employed by cloud service providers, mainly because it's fascinating, cutting-edge stuff. Sooner or later, many of these advances will trickle down to rank-and-file IT. But if anyone claims you can boil your IT ocean into a cloud if you just buy the right "solution," tell them to stop fogging up the joint.