Virtualization and the Cloud: NOT the Same Thing

• By Jennifer Skelly
• 11/30/11

The terms cloud computing and virtualization are often--and mistakenly--used interchangeably. They are not the same. Indeed, comparing the cloud and virtualization is a bit like comparing an iPod to its earbud. While the earbud is a key component of the iPod, it is just one part of a bigger whole. The same goes for virtualization and the cloud.

And just as an earbud can be used elsewhere, virtualization can happen without the cloud. Indeed, as many institutions can attest, virtualization often plays a vital role in university data centers, computer labs, and more--with no cloud in sight.

So what is virtualization exactly? Virtualization comes in many flavors: storage, desktop, memory, operating systems, servers. Put as simply as possible, virtualization allows you to do more with less. Most computers aren't used to their full capacity. Indeed, the average enterprise server runs at 5 to 10 percent of its capacity. Virtualization offers a way to consolidate the number of servers you operate by using just one machine to handle applications that had previously been handled by several physical servers.

This neat technological trick is performed with virtualization software, which was initially pioneered by IBM back in the 1960s. Today, it's one of the hottest IT fields on the planet, with players such as VMware, Citrix, Dell, Microsoft, and Oracle all duking it out for market share. Essentially, the software partitions a server into multiple virtual computers, each isolated from one another and with the capability to operate just like an actual server.

In a way, virtualization software acts like a mirrored fun house, tricking the system into believing there are more servers than there really are. But the benefits are very real. Virtual servers use less hardware, space, and power--and require less cooling--all of which reduces infrastructure and administrative costs. And when the need for more server space arises, users can carve a virtual server out of the existing hardware, rather than going out and buying another machine. What may have taken weeks to implement before can now be done in mere minutes.

The same principle underlies storage, desktop, memory, and operating system virtualization: The system fools the computer into handling multiple users' needs on one piece of hardware--a useful feature for universities that need to manage multiple machines from one location or provide identical services to multiple users.

It's safe to say that virtualization is already in place on the servers used by most public cloud providers, although the end user would never notice or see it. When it comes right down to it, the decision to virtualize an institution's servers or go to the cloud is not really a technological choice--it's a business decision.