Desktop Virtualization

Try to spark a debate about the value of server virtualization, and the closest thing to controversy you’ll get is whether you should virtualize 60 percent or more like 90 percent of servers. If you’re not virtualizing servers today, reaping savings from running fewer boxes, you’re a technology laggard.

Kick that debate over to desktop virtualization, however, and you’ll face plenty of skepticism. Can virtual machines deliver the Web-centric, mobile, highly personalized desktop experience that company employees have come to expect?

Having tested eight desktop virtualization platforms over the past six months, we think they can -- if IT teams implement them properly. Virtual desktops can provide the same look and feel as a physical workstation, including personalized features such as toolbars, instant messaging clients, browser add-ons, and other software. Mobility’s still a problem, and there are other pitfalls, which we’ll explore. But the advantages are strong enough that companies will want to look at desktop virtualization.

While the exact future of the business desktop is a moving target, one thing’s for sure: The conventional OS that contains 50 million lines of code is dying a slow death. Prepare to bury your copy of Windows Vista in a time capsule so a future generation can one day laugh at how unsophisticated we were.

We can safely make another bet. Desktop virtualization won’t replace terminal services, where users execute applications centrally with screen changes being streamed to the client (presentation virtualization). Nor will desktop virtualization replace application virtualization, and it won’t slow the move toward software as a service, where applications are accessed via the Web from vendors’ data centers. Instead, virtual desktops most likely will complement SaaS by serving as a "sandbox" -- a safe haven for accessing data and applications of all types, whether inside or outside the enterprise.

The breakthrough with desktop virtualization is that it’s a completely independent operating environment, free from the traditional limitations of presentation and application virtualization. There are more radical notions than this, like upstart Stoneware Inc. ’s WebOS, which tries to eliminate the conventional OS entirely, by plopping a Java-based doppelgänger right in a browser. Google (Nasdaq: GOOG)’s proposed Chrome OS appears to be aiming to do something similar on bare metal.

But most companies will need much more than a Web browser at the presentation layer, since they need to secure and deploy custom applications that may never be Web-enabled. Perhaps those applications need to work across a wide variety of operating systems and on a wide variety of handheld devices. These tasks and more are what virtual desktop infrastructure (VDI) software was built to handle.

Desktop virtualization isn’t a new concept, since IT pros and power users have been using it for years on their own systems for development, support, and special application access. What’s new is the mainstream deployment of many thousands of virtual desktops served out by your hypervisor of choice and accessed via your favorite remote viewing protocol, such as ICA or RDP 6.0.

In the InformationWeek labs, we put eight vendors’ products through the wringer, and we talked with multiple IT managers who’ve implemented a VDI. We’re convinced that desktop virtualization is indeed ready for prime-time corporate use. Getting it right, however, takes a sharp focus on end-user needs as well as the technology infrastructure.

It first helps to understand some of the unique technology challenges that are accelerating acceptance of desktop virtualization. The biggest benefits we hear over and over from IT managers involve efficiency gains when updating and securing PCs, cheaper desktop hardware, and greater flexibility than conventional thin-client approaches. Drawbacks include the data center capital costs, mobility limits, and reliability concerns. (See boxes, pp. 3 and 5.)

Another risk is that the technology’s still evolving, which can make nailing down the ROI tough. Take moka5 Inc. ’s effort to fix the offline accessibility problem by shifting more of the processing burden of running the virtual desktop from the server back to the client when the PC’s offline. This approach lets employees access virtual desktops without Internet access, such as during plane trips.

Great concept, and in our labs moka5 did access the virtual desktop seamlessly. But the PC needed a fairly fast processor and at least 2 GBytes of RAM to run well. That can eat into expected savings from cheaper hardware. Conversely, if you use virtual desktops to shift processing off PCs and save on client hardware, you’ll need to beef up server infrastructure to deliver the performance employees expect. That brings us to the first strategic imperative when crafting a desktop virtualization battle plan...

— Randy George (rgeorge@nwc.com) is an industry analyst covering security and infrastructure topics.

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