You can virtualize individual applications -- using products such as VMware's ThinApp, Microsoft's App-V or Citrix XenApp -- and then deliver those into a virtual desktop or stream them down to a physical PC on demand and have them run locally. "Application virtualization is really software distribution done in a different way," Accenture's Slattery says.
Touchstone Behavioral Health ran into a situation where essential hardware wasn't supported by the virtualization provider -- a problem that CIO Steven Porter called a "deal-breaker" for continuing the pilot.
The technique also promotes stability and eliminates application conflicts by isolating the application from other Windows apps as well as from the Windows operating system. No changes are made to the registry or other settings, so this mechanism can be used to, for example, run two versions of the same application side by side, or to avoid compatibility issues when running an old Windows XP application on top of the Windows 7 operating system.
User state virtualization
Finally, there's personalization: Virtualization of each user's personal settings, such as wallpaper and other configuration preferences, by storing that data in roaming user profiles or by using third-party tools from vendors such as AppSense or RES Software.
Some third-party tools can store more granular operating system and application settings and even one-off programs. Then the basics are loaded into a plain vanilla nonpersistent VDI session or a hosted shared virtual desktop session at runtime. The rest of the settings and information, such as Word macros, are streamed on demand as needed so users can get up and running more quickly.
"Roaming profiles give users the flexibility to roam between [devices] and preserve the user experience," says Gartner's Wolf.
Personalization tools offer the best of both worlds. They allow users of nonpersistent virtual desktops to maintain a customized work environment while administrators enjoy the efficiencies that come from maintaining a small group of shared virtual desktop image files. For this reason, says Gartner's Margevicius, "this will be the key technology for most customers over time."
"Customers ignore personalization at their peril," says INX's Kaplan. Not all users need a personalized desktop, he adds, but in some corporate cultures, deployments that fail to accommodate this demand won't succeed.
The lesson here, says Gartner's Wolf, is that many different pieces of operational software, including management tools and desktop antivirus software, will need to be tied into your desktop virtualization solution, so selecting the right products is critical. "There will be a high exit cost" for making the wrong choice and then having to backtrack, "so don't rush into a bad decision," Wolf warns.
Touchstone: Holding off virtualizing clients for now
Steven Porter, CIO at Touchstone Behavioral Health, recently completed a virtual desktop infrastructure proof of concept with VMware View. "We were very pleased with the results," he says. But he has decided to wait until some hardware incompatibility issues are resolved before he moves VDI into production mode.
"There's no real cost savings," he says, noting that additional virtualization and Windows licensing charges add $300 per laptop to his costs. Over the first three years, he says, "it's about a wash" when compared to what he pays now to run Windows on each physical machine. "But you gain in security and convenience. The real win is in end-user satisfaction."
Users will benefit from faster provisioning of desktops -- or re-provisioning when things go wrong. Other gains include greater reliability, better security and support for devices the user brings to work.
Porter says he'd like to get out of the business of owning hardware, most of which is laptops used in the field by Touchstone's staff. Many employees have their own computers and use the company laptop only to access electronic medical records and email. "That's 30% of my annual spend. I could divert that to projects that make more sense from a productivity standpoint," Porter says. "A lot of people are carrying my laptop during the daytime and pulling out theirs at night. They'd be more comfortable with one machine of their own choosing."
The technical issue holding back the project is the incompatibility of a USB-attached signature pad that's used in the field. The VMware View Client sees it as a mouse, and although the signature pad's manufacturer offers a "clunky" workaround, Porter feels that's too much to ask of his users, and he doesn't want to replace the signature pads. So he'll wait for a real solution.
More importantly, users in the pilot weren't sold on desktop virtualization technology either, although they would rather use a computer of their own choosing -- something that VDI enables. "They were ambivalent," Porter says. He eventually plans to roll out the virtual desktops. But before doing so, he says, he'll build a case study to show users "where they'll start seeing benefits, and that it will make their lives easier."
— Robert L. Mitchell
IT organizations often perceive the different options as competing solutions, says Gartner's Margevicius, but the technologies are actually complementary. One approach may be better suited than another for a given use case, but two or more technologies may also be used together to create solutions that more closely address the needs of specific groups of users.
For example, an IT organization might deploy a virtual desktop to the user with Microsoft Office installed in it, and deliver other programs onto the virtual desktop using application virtualization.
The user sees a unified desktop environment, while IT improves stability by avoiding application-induced conflicts.
How a hosted virtual desktop infrastructure meshes with the rest of your data center depends on what you already have for back-end infrastructure and what your plans are for your virtual desktops.
Calculate the implications for IT infrastructure
IT organizations that have already been down the virtualization road with servers have a leg up. They should be able to leverage at least some of their existing license agreements, as well as management tools, network equipment, networked storage and other infrastructure.