One of the main goals with desktop virtualization is to reduce the number of required desktop images. The fewer number of images, the easier it is to support and maintain the desktop environment, which makes desktop virtualization so promising when compared to the traditional desktop approach. The goal is a single image, but oftentimes, other factors play a role in slightly increasing that number. Take, for instance, the ABC School District Reference Design.
The design called for 5 different desktop images, as shown in the figure.
If you look at the specifications, many of the configuration details are identical. So why create different images for different user groups? It really came down to future plans. The ABC School District decided that it would be easier to design the environment with unique images for the different areas:
- Middle School
- High School
- High School Blade PCs
- Teachers & School Administrators
- Support Staff
Ideally, we probably could have reduced the number of images, with the aid of application virtualization. But the school district wanted to make sure unique images were available if certain applications were later identified to be incompatible with the different forms of application virtualization (application streaming and application hosting). Also, it would have been possible to integrate the High School and High School Blade PCs images into a single image, but because the Blade PCs are delivered without a hypervisor, there would be variations in the device drivers (something Provisioning services can easily handle). To make the management of the images easier, it was determined to separate these images as well.
So we are left with 5 images. Not bad for an environment with 20,000 end points.