Just as virtual servers can be created on a single physical computer, the user desktop can be virtualized as well. The reasons for desktop virtualization are the same: cost savings and improved efficiency. There are two different types of desktop virtualization:
- Local Virtual Desktops – Once a desktop or laptop computer has been set up with an operating system it may then have virtualization software installed as an application. For example, installing Oracle Virtual Box on your Windows or Apple computer will allow you to create VMs onto which you may install other “guest” operating systems. Thus, you could work with both Windows and Unix applications on a single computer. Another use of local virtualization would be for testing software or security applications. Any unfortunate events happening on the guest OS would not affect the host or other guests. The misbehaving guest can simply be deleted or reset to the original state.
- Virtual Desktop Infrastructure (VDI) – This is an alternative to traditional desktop computing. VDI moves the user desktop to a virtual machine running on a server in the data center. Rather than providing every user with a powerful desktop or laptop running a local OS and applications, users are provided with an inexpensive computer with moderate processing power. The purpose of the computer is to provide the user with a screen, keyboard, mouse, and some USB ports for peripherals. The user connects to the remote desktop using RDP (Remote Desktop Protocol) or VNC (Virtual Network Computing). All user applications are run from the virtual desktop and storage is provided by the server environment. This technique has been called “thin client computing” in the past. The user could also access their virtual desktop over a VPN (Virtual Private Network) from home or while traveling. The user’s desktop can be customized (persistent) or the user would always use an enterprise standard desktop (non-persistent)
Server and desktop virtualization are important tools that create opportunities for cost reduction, especially in the data center. Desktop hardware costs are also reduced with VDI, and both of these solutions reside within the enterprise data center. Another technology, cloud computing, allows those resources to be located in other data centers that are either privately owned or accessed over the public Internet.
You very well may see a question or two on the Network+ exam about desktop virtualization, so be sure you understand these two popular approaches to traditional user computing.