One of the biggest appeals of a virtual desktop infrastructure (or any thin-client computing system) is it can dramatically reduce desktop hardware costs. But dependence on existing operating systems and security demands can keep your organization from reaping the benefits of thin clients.
Thin-client computing allows desktop machines to run a client component that connects them to a terminal server. The server receives keyboard and mouse input from the client machines and returns screen refreshers to the users based on their input. With thin-client solutions, administrators do not have to worry about whether a desktop computer is capable of running various corporate applications. This means that an organization may not have to replace machines as often: As long as a desktop is functional and is capable of running the client component, it can be used as a thin client.
Saving money by using the same desktop hardware may sound appealing, however the logic behind this approach is at least partially flawed.
The vast majority of thin-client implementations involve desktop computers that run the client on top of a traditional OS, like Windows XP or Vista. This limits cost savings because the hardware's life span isn't going to be as long as promised. For example, Windows Vista probably can't be installed on a 10-year-old computer.
In addition, full-blown operating systems need to be maintained. In order to keep the environment secure, the desktop OS needs to be patched regularly -- just like in a client/server environment. Depending on the security measures taken, desktop OSes may also be vulnerable to things like user tampering and malware infections.
The most secure thin-client deployment I have seen involved a healthcare facility that replaced all of its desktop PCs with dumb terminals running an embedded version of Windows. These terminals were low cost and weren't susceptible to any of the security or maintenance headaches associated with a full-blown OS. Unfortunately, this technique prevented the organization from using the desktop computers it already owned. In addition, the organization was unable to take advantage of the Remote Desktop Protocol improvements that were released over time.
Universal Desktop Converter
The best approach for connecting users to a thin-client environment varies by organization and depends on the hardware and software deployed. One possible solution is to convert existing desktop PCs into dedicated terminals. Several vendors offer products that accomplish this task in a variety of ways, but IGEL is a vendor that recently caught my attention with its Universal Desktop Converter.
Upon booting the PC from the USB device, the Universal Desktop Converter automatically updates the PC's firmware, turning it into a fully managed terminal capable of delivering applications based on Citrix, Terminal Services and VMware. The firmware update installs an embedded Linux OS that includes basic hardware drivers, a terminal client and some desktop management components.
The Universal Desktop Converter is a replacement for the PC to TC Conversion Card currently offered by IGEL, which will be retired at the end of 2009. The PC to TC Card is an expansion card containing firmware similar to what is used by the Universal Desktop Converter. The computer's hard drive cables are removed from the hard drive and connected to the PC to TC Card, allowing the computer to boot from the card. As you can imagine, updating the PC's firmware from a USB device is typically going to be a lot easier than taking apart a PC and making hardware modifications.
The Universal Desktop Converter takes an innovative approach to providing existing desktops with terminal connectivity while removing the headaches involved in running a traditional operating system. Numerous competing products are available, but I have yet to see one that takes this type of approach to providing thin-client connectivity.
ABOUT THE AUTHOR:
Brien M. Posey, MCSE, is a Microsoft Most Valuable Professional for his work with Exchange Server and has previously received Microsoft's MVP award for Windows Server and Internet Information Server (IIS). He has served as CIO for a nationwide chain of hospitals and was once responsible for the Department of Information Management at Fort Knox. As a freelance technical writer, Posey has written for Microsoft, TechTarget, CNET, ZDNet, MSD2D, Relevant Technologies and other technology companies. You can visit his personal website at www.brienposey.com.