A new report out from Forrester takes a chart-filled look at cloud computing, offering the analyst firm’s own definition of the cloud and attempting to dispel three myths they have noticed. Since we at GigaOM buy pretty heavily into two of these so-called myths — namely that a cloud is comprised of a scalable virtualized server environment and that it’s a low-margin business — I was eager to see where we had been led astray.

But I don’t think we have been. The report takes a big tent approach to clouds, applying the cloud moniker to both the end user market and to a class of goods it calls infrastructure-as-a-service. That’s far above the hardware level where Amazon, Mosso and GoGrid sit, and includes software-as-a-service and even consumer web applications like Zillow or Flickr. Such a broad definition doesn’t really help clear any of the fog for the industry, and would likely only serve to make the term “cloud” even more of a marketing tool than it already is.

As the chart shows, Forrester sees clouds where most people see web applications. The lower three tiers are in line with a post written by the CEO of RightScale, a startup adding a platform on top of the physical infrastructure of the cloud. We’ve tried hard to distinguish between the hardware layers and the layers resting on it, such as platforms-as-a-service and APIs offered for mashups, which Forrester calls application-components-as-a-service, but are we being too dogmatic? What we’ve called the cloud, Forrester calls hardware-as-a-service (HaaS). Personally, I could do with fewer aaSes in my life, but regardless, since our readers are pretty savvy on this topic, what do y’all think?

chart Copyright © 2008, Forrester Research, Inc.

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