Virtual Desktop Infrastructure (VDI) may be just what IT needs to rapidly allow legacy applications to be accessed on mobile devices, but it's not without flaws.
Virtual Desktop Infrastructure (VDI) has been around in some form for more than a decade. Products such as Citrix and Microsoft's Terminal Services allowed an end-user desktop to be run from a server. In some cases, specialized terminal devices harken back to the dawn of computing, essentially acting as dumb terminals that provided a screen and keyboard, while all processing and storage were run from a distant server. While this terminal mode of computing only caught on in limited circumstances, there has been a renewed interest in VDI technology as mobile devices have entered the enterprise.
Legacy: mobile's greatest enterprise challenge
One of the major stumbling blocks to widespread adoption of mobile devices in the enterprise is the prevalence of legacy applications. Smartphones and tablets will readily connect to email and intranets, but ERP, CRM, and custom in-house applications are another story. Corporate IT departments are faced with an array of equally daunting options: replace legacy applications with newer mobile friendly technologies, rewrite user interfaces to support mobile devices, or write custom mobile clients for legacy applications. VDI presents a fourth road that, while not without caveats, might provide a stopgap measure to get your mobile devices and enterprise applications talking.
Of apps and desktops
If you've ever had the (dis)pleasure of connecting to a traditional Windows desktop from your tablet, you've probably realized this is a difficult way to perform a computing task. The smallest desktop screens in circulation have nearly double the area of the average tablet screen, and it's no longer extraordinary to see desktops equipped with a pair of huge monitors. Desktop operating systems and applications are designed for this massive amount of screen real estate, often taking advantage of superior screen resolutions. Furthermore, these interfaces are often full of tiny icons and text fields that present no problem to a mouse and keyboard-equipped device, but are an exercise in frustration to a stubby fingertip.
Clearly, providing end users with a virtual desktop and slew of icons is not the best way to get mobile devices talking to your legacy world; however, more recent VDI packages have begun serving single applications. Rather than forcing users to navigate a desktop, these packages allow users to launch a single application that's hosted on a virtual desktop server. Even better, some of these packages attempt to add mobile UI elements to existing applications. Citrix's XenApp, for instance, presents users with mobile-style icons for each application that exists on the server, and translates common mobile interface elements like two finger scrolling and pinch-to-zoom into their desktop equivalent. This is clearly not on par with a native application experience, but can provide some level of familiarity to users with little effort on IT's part.
Applications can also be enhanced for mobile access on the server end, without building a mobile development capability within your organization or hiring expensive outside help. You could use your existing ERP developers to create a dozen screens and reports that have a limited number of fields, and space them more appropriately for mobile use, without writing a single line of mobile code. Again, this is significantly less streamlined than a true mobile interface, but it's also significantly less costly.
Another challenge of mobile devices in the enterprise is managing a diverse pool of operating systems on tiny devices that are readily lost or misplaced, and potentially loaded with untrustworthy apps and games. Rather than attempting to enforce compliance and adding a major management burden to IT, VDI essentially separates the device from the application and data. Since corporate applications and their associated data are contained on a server, and the mobile device does little more than provide a screen and input, an untrusted device can still securely access corporate applications and data. MDM purists will argue that this is not the most secure way to manage mobile devices, but it's certainly less painful than doubling or tripling the number of devices that must be tracked and managed by IT using traditional end-user device management techniques.
Plan for post-VDI
There are lots of reasons to consider VDI to rapidly put mobile devices to work in your enterprise without creating a significant amount of work for IT. However, even the best VDI technologies, combined with tweaks to your enterprise applications, cannot match purpose-built mobile applications. When considering VDI for mobility, realize that it's an imperfect solution, and communicate to users that it is part of a longer-term shift to mobile platforms.