Remember a few weeks ago when I asked what's the cloud, if not a collection of services offered via Web protocol – the real question being, how is the cloud that different from SOA?

No? Well, I did. You can see for yourself by visiting the original post.

Anyway, the question raised its little bald head again this week when I read this post by Stacey Higginbotham of GigaOm. Higginbotham has been following a series of HP webinars on cloud computing and how it can fit into corporate IT structures. The CTO of HP's Cloud Service Strategy, Russ Daniels, apparently impressed her with his vision of the cloud as a “unified, persistent repository for data that applications or people can access.”

But overall, she walked away disappointed because “...most of HP’s detailed talk of clouds in the first webinar was depressingly similar to the idea of service-oriented architecture.”

Apparently, much of the presentation centered around how HP could help you deliver IT as a service inside the enterprise. She's right: That does sound like SOA.

The post itself left me with more questions than it answered, but taken with the comments, it was an interesting discussion. In fact, it's one of those instances that happen too often in IT where you think you know what something means and then a vendor or an analyst introduces an entirely new spin on the term.

There seems to be some question as to what HP and other vendors mean when they're talking about cloud computing in the enterprise. Specifically, the question is: Are vendors really just repackaging SOA as internal clouds?

David Linthicum first pointed this out in January, when he asked “Will SOA Morph into Private Clouds?”

“What's interesting here is that they can repackage an existing concept that many are pushing back on these days, as something new and exciting, but they are basically the same SOA concepts. Heck, we did that with SOA, which was based on existing architectural patterns, so why not private clouds and cloud computing? Perhaps it's all in the marketing.”

Ah, marketing. That old con.

Someone did bring this up in the GigaOm discussion thread, prompting Rebecca Lawson of HP added a comment protesting that HP did not like that term, because HP felt it “muddies the water.” (Full disclaimer: Although I do have an aunt by that name, this Rebecca Lawson is not related to me.)

I agree, but, seriously, since when do IT vendors worry about muddying the waters with new terms and acronyms?

She distinguishes between  global-class services, such as you would see with FaceBook or eBay, and enterprise-class services, which is what you would get if large companies service-enabled their infrastructure for consumption internally and possibly with a few external supply chain partners.

Obviously, there's a difference of scale, but again, how is this not SOA?

Perhaps it really doesn't matter – as long as they're not repackaging the same mistakes, too. In a different post, Linthicum warned this is a real possibility:

“The danger is that many of the same mistakes made by the same people will be repeated within cloud computing projects. The hype around cloud computing will make this more likely.”

If you don't want to fall victim to these mistakes, Linthicum offered this advice:

1. Lead with architecture, not the solution. This means look at cloud computing as one way to address your architecture needs, as opposed to just jumping on-board because it's the latest, greatest thing.
2. Don't expect the people who failed you at SOA to deliver on cloud. That's just asking for trouble.
3. Understand how the cloud and SOA link together.

I'd love to more on that last one.

You might also want to read this piece by enterprise architect Mike Kavis, aka the Mad Greek, admonishing IT to apply the hard lessons of SOA to the cloud. He's got an excellent list of advice that, frankly, could apply to anything IT embraces, whether it's SOA or the cloud.

Also, if you're interested in hearing more from HP on the cloud, check out  Higginbotham's follow-up post, "Cloud Computing Is a Tool, Not a Strategy.” It offers a nice reality check on how ready cloud computing is for enterprise adoption.