Bill Claybrook

When we first heard about cloud computing, public clouds got most of the attention. But as IT managers looked at the security risks of having data outside the corporate firewall, they turned their attention to private clouds, which analysts and various surveys suggest will get more enterprise investment in the next few years.

But private clouds have their share of challenges too. There are management issues and operational processes to figure out. And, of course, an on-premises private cloud needs to be built internally by IT, which takes time, money and a climb up the learning curve. Indeed, the transition from a traditional data center -- even one with some servers virtualized -- to a private cloud architecture is no easy task, especially given that the entire data center won't be cloud-enabled, at least not right away.

When cloud computing became a topic of discussion a few years ago, public clouds received the bulk of the attention, mostly due to the high-profile nature of public-cloud announcements from some of the industry's biggest names, including Google and Amazon. But now that the talk has turned into implementation, some IT shops have begun steering away from public clouds because of the security risks; data is outside the corporate firewall and is basically out of their control.

Tom Bittman, vice president at Gartner, said in a blog post that based on his poll of IT managers, security and privacy are of more concern than the next three public cloud problems combined. He also wrote that 75% of those polled said that they would be pursuing a private cloud strategy by 2012, and 75% said that they would invest more in private clouds than in public clouds through 2012.