Many IT people today think they have a pretty good idea about what virtualization is, and even know some of the companies that sell it. But perhaps the people that are confused have a better grasp on the situation, because they know that they don’t quite understand it all. And that can potentially prevent leaping in a direction that does not provide the results you thought it would. To make it more challenging, many vendors are bringing completely different architectural models to market, so it’s hard to stack rank “feeds and speeds” since in many instances you are evaluating fundamentally different approaches to solving problems. And these approaches have enormous short and long term implications to all of your infrastructure, some that are yet to be fully vetted. Let me see if I can help reduce the confusion by explaining a few things about the various virtualization technologies.
Let’s start with the one that I think people know the most about – Server Virtualization. (I know this is pretty basic, but stick with me on this, and I think you’ll be better off in the end.) The primary technology for this is called a hypervisor, and it is designed to abstract the hardware from the operating system. By “virtualizing” the hardware, or creating a “virtual container” for the OS, one piece of hardware can be used for several operating systems, when only one would normally be allowed. This has led to huge cost savings and greater flexibility in the datacenter.
Moving up the computing stack a bit, we come to Desktop Virtualization. This is where a client operating system is abstracted from the local computing device, thin client or otherwise. It just means that the OS is running somewhere other than where the user is sitting, usually in a datacenter. Desktop Virtualization has actually been around in various forms much longer than Server Virtualization, going back to the mainframe days when people would access the system from remote terminals. Now that desktop computing has been around for so long, many of us have forgotten and see this as revolutionary. Although the concept is not new, there are some innovative new ways to accomplish it, with the main categories of solutions being various forms of “terminal servers”, “virtual hosted desktops” (also known as VDI), or blade PCs. These are completely different technologies than Server Virtualization, and are adopted for very different reasons, like access security or hardware cost reduction. It is also important to note that the Virtual Desktops (or remote OSes) may be running on Virtual Servers, or they may be running on physical servers – but the technologies are not dependent upon one another.
Now we get to Endpoint Virtualization, even higher in the computing stack, and perhaps the least understood. Again, it is a collection of technologies that is sure to continue growing, but this time the purpose is abstracting the assets a user needs to be productive, like applications, profiles and data, from the operating system. These technologies have more to do with end-user productivity by allowing applications and such to be independent of the operating system and device. This allows a user to be more mobile and flexible, as his assets are not tied or dedicated to a specific environment or location. Again, Endpoint Virtualization technologies, including application virtualization, application streaming, profile virtualization, and others, are completely independent of the previous two categories, and can exist in all environments, both physical and virtual. For example, application streaming can help to consolidate application management, licenses and distribution, and deliver applications automatically to the right people, when they need them, regardless of where they are, or whether they are on a laptop in another country or a terminal server in the home office.
I believe that the greatest source of confusion today is a lack of understanding that Desktop and Endpoint Virtualization are separate solutions that solve different problems, and they should be evaluated on their own merits. Often, companies that assume that virtualizing their desktops solves more problems than it does, wind up with a more complicated and expensive solution than is really necessary. Likewise, Endpoint Virtualization does not address the location or security of the operating system itself, but its benefits extend to physical systems as well.
Tune in next time to look at how to go about selecting the right technologies to solve your biggest problems, without making them worse or more expensive.
- Brian Duckering
Previous Blog: Wow! I didn’t know Symantec did Virtualization