Like most young industries, the desktop virtualization tools business is a free-for-all. And with all the corporate consolidations, product promises and twisting terminology, IT managers must wade in at their own peril.
But, in truth, most IT managers look at a bigger mess every day when they face the job of bringing order to the chaos of their enterprise desktops and laptops. It makes perfect sense that so many are pinning their hopes on desktop virtualization and on application virtualization as potential sources of welcome relief.
There are a few basic ways to virtualize the desktop. One way is the shared remote desktop, where all changes are made on a server by an administrator. Also known as thin-client computing, this approach has been in use for years. End users have to be online to access the desktop.
An end user could possibly log in even for only one time, and the system can generate a profile, email and application access for that person. When they log off, all of their information is deleted. Technologies like Citrix's Presentation Server and Microsoft's Terminal Services offer this model.
"For us, you never have to worry about protected healthcare information because you can't save anything in that profile," said Rich DeBrino, CIO at Compass Health Inc. in Everett, Wash., adding that it's great for people who have the same computers.
Laptops are another story because end users tend to futz around with them more by doing things like adding software and changing configuration settings. Also, they tend to travel with their PCs, so they are occasionally offline. So, for this crowd, it makes sense to run a virtualized operating system in a virtual machine on an end user's own PC.
In another type of virtually hosted desktop model, end users can connect to a server to get a single remote hosted desktop. This model requires a delivery infrastructure and a connection broker. A connection broker is used to authenticate the user and find the correct desktop.
Some IT shops may also elect to have blade PCs host individual sessions for end users.
IT managers eye streaming and application virtualization
Application virtualization and streaming are two related technologies often associated with desktop virtualization. Application virtualization is when an application is encapsulated in a virtual container on the operating system, thereby avoiding management conflicts and upgrade problems associated with installing applications directly on the operating system.
Streaming is when the application, though not necessarily all of the application, is packaged and streamed to the client. Citrix's Project Tarpon streaming technology, which is now a feature in Presentation Server, is an example of this. Altiris Inc.'s SVS and Microsoft's SoftGrid are examples of application virtualization products.
Dave Driggers, desktop team leader at Alabama Gas Co. in Birmingham, Ala., said he is interested in Microsoft's SoftGrid application virtualization technology to prevent the need to patch applications on every desktop. Using that technology, end users can work in an offline situation. "We would only have to worry about the OS, and it would be pristine," Driggers said.
Another reason to run an application in a virtualized environment is when that application isn't available any other way. For example, Michael Cherry, an analyst at Directions on Microsoft, a Kirkland, Wash.-based consulting firm, said, "Microsoft never made a version of Visio for the Mac, so I run VMware's Apple product, which allows me to run a licensed copy of Visio."
Today there are lots of individual products to virtually host desktops that in many cases sit side by side with server virtualization technology. Vendors are working hard to compile a suite that is completely integrated.
"Everything we talk about today is real, but if you want virtually hosted desktops, you need Vendor A plus B and C," said Brian Madden, a Washington, D.C.-based consultant.
More options from VMware and Citrix
Citrix Systems Inc. and VMware Inc. are two vendors with expansive toolsets. Citrix released in April its Desktop Delivery Server that lets end users download desktops on demand. The company recently acquired XenSource Inc., which provides the virtual machine infrastructure. Citrix owns application streaming technology through its acquisition of Ardence Inc. in December.
VMware sells its Virtual Desktop Infrastructure for server-hosted desktops. The company acquired Propero, a New York.-based connection broker, for $25 million in June. The company also sells ACE, a client technology used to give end users a virtual computer running on their own hardware. You can also use ACE to run multiple virtual machines with different operating systems within a desktop.
Former Citrix partner, Provision Networks Inc. in Reston, Va., has a broad suite of software that combines server virtualization and virtually hosted desktops into one. But unlike VMware and Citrix, the company does not have a hypervisor -- the virtualization platform that lets multiple operating systems run on a single piece of hardware. For that piece, Provision has a partnership with Virtual Iron Inc. in Lowell, Mass., which has a hypervisor based on open source Xen technology.
More options for virtual hosted desktops appear every day. IT shops need to think long and hard about exactly what it is they are trying to do before they jump in, particularly if they're looking to reduce their work load and control costs.
"My fear is that, yes, you may reduce the work done on a per-desktop [basis] and it may be more efficient," Cherry said. "But you're not likely reducing the work -- only moving it to another place where it still has to be done," he said.