Stormy weather: 7 gotchas in cloud computing

When the computer industry buys into a buzzword, it's like getting a pop song stuck in your head. It's all you hear. Worse, the same half-dozen questions about the hyped trend are incessantly paraded out, with responses that succeed mainly in revealing how poorly understood the buzzword actually is.

These days, the hottest buzzphrase is "cloud computing," and for John Willis, a systems management consultant and author of an IT management and cloud blog , the most annoying question is this: Will enterprises embrace this style of computing?

"It's not a binary question," he asserts. "There will be things for the enterprise that will completely make sense and things that won't."

The better question, he says, is whether you understand the various offerings and architectures that fit under that umbrella term, the scenarios where one or more of those offerings would work, and the benefits and downsides of using them.

Even cloud users and proponents don't always recognize the downsides and thus don't prepare for what could go wrong, says Dave Methvin, chief technology officer at PC Pitstop, which uses Amazon.com's S3 cloud-based storage system and Google Apps. "They're trusting in the cloud too much and don't realize what the implications are," he says.

With that as prologue, here are seven turbulent areas where current and potential users of cloud computing need to be particularly wary.

Costs, Part I: Cloud Infrastructure Providers

When Brad Jefferson first founded Animoto Productions, a Web service that enables people to turn images and music into high-production video, he chose a Web hosting provider for the company's processing needs. Looking out over the horizon, however, Jefferson could see that the provider wouldn't be able to meet anticipated peak processing requirements.

But rather than investing in in-house servers and staff, Jefferson turned to Amazon's Elastic Compute Cloud, a Web service known as EC2 that provides resizable computing capacity in the cloud, and RightScale, which provides system management for users of Web-based services such as EC2. With EC2, companies pay only for the server capacity they use, and they obtain and configure capacity over the Web.

"This is a capital-intensive business," Jefferson said in a podcast interview with Willis. "We could either go the venture capital route and give away a lot of equity or go to Amazon and pay by the drink."