Leave it to Rob Carter, the CIO of FedEx, to clarify what's really powerful about cloud computing. Carter, the company’s CIO since 2000 and an InformationWeek advisory board member for almost as long, has a knack for discussing technology in a way that cuts to the business payoff, but without leaning on buzzwords that whitewash the complexity involved.

Carter boils down cloud computing, when applied to IT infrastructure, to "general purpose computing." It's the ability to connect servers, networking, and storage that are "workload agnostic," meaning the jobs they handle can be shuffled around among a company's computers, so those machines are used as efficiently as possible.

Just last fall, FedEx opened a new data center in Colorado Springs based on this idea of general purpose computing. It uses commodity x86 servers, each with just a single 10-gig Ethernet cord into the back for networking, replacing the bevy of wires of the past for host-bus adapters, NIC cards, etc. Before applications move into the new data center, they're "commonized"--revised to use the same database and messaging technology, for example, so they can move easily among servers. FedEx is using this cloud infrastructure inside its own data center---a private cloud--but Carter says workloads could easily shift to public clouds run by vendors such as Amazon and others, if that made strategic sense down the road.

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IT pros, jaded by relentless tech hype, love to point out that "This is nothing new." Mainframes have long done virtualization, so a private cloud isn't all that different. Cloud computing understandably has triggered this reflex, as every vendor tries to label what it does as cloud. Some purists may also quibble that what FedEx is doing isn't really cloud, if it's not a fully self-provisioning and multitenant environment.

Carter isn't a bit worried about whether any of this fits this or that cloud definition. But he is unequivocal about this: The highly virtualized computing environments companies can build today are unlike anything that has come before them. In his words:

"I started in the late '70s, right around '80, working this stuff, so I've ridden every wave from mainframe to minicomputers to PCs to client server to object-oriented--let's throw CASE in there somewhere back in the '80s--to Internet technologies. As those waves crashed, we and everyone else have remnants of those things. What's happening now--for the first time, in my opinion--is there 's truly a general-purpose computing environment that's workload agnostic. You can throw different kinds of workloads on the same computing server infrastructure. There's network convergence--all the networks are IP, there's not a bunch of unique protocols. And there's converged storage technology." Then there's software like Java that can make it all "very portable across platforms."

Understand, Carter is not an easy sell on the latest, greatest emerging technology. Back when the world (including us at IW) was going a bit gaga over RFID tracking technology, Carter was a voice of reason. So when Carter embraces a technology, I, for one, listen. (Carter and I discussed these ideas late last year, after he spoke at this CIO event.)

The economics of the technology change are powerful. In FedEx's case, it lets them build a new data center and retrofit a second one to this private cloud environment, fill it with new hardware, rewrite the software as needed to take advantage of this environment, and still have a compelling ROI. Says Carter:

"What's happening, and this is such a big deal in our world, is that for the first time ever, you can make investments in a whole new class of technology for about the same price of just maintaining the base."