APPLICATION & DESKTOP VIRTUALIZATION (VDI)
Thanks to the pioneering efforts of VMware 12 years ago, virtualization has become commonplace in today’s IT environment.
The first step for most companies is server virtualization, where multiple server images are run on one host system taking advantage of the unused CPU cycles and other resources that were commonplace in a single image physical server. The financial and operational benefits of this approach were undeniable, and this led to its widespread adoption.
Then about five years ago, this concept was translated to the desktop with the Virtual Desktop Infrastructure (VDI) announcements from VMware and Citrix. The problem was that this approach was far more difficult and expensive to implement than server virtualization, and the initial adoption of this approach has been slow at best. Well now in the last 18 months or so with some improvements in server horsepower, along with some other technology like SSD and RAM disks, the main concerns of cost and speed have been effectively addressed. This has made VDI a hot topic again since its benefits in centralized administration and improved data and access security are significant.
VDI, with an individual virtual machine per user running Windows 7, is not the only way to approach desktop virtualization though. Citrix has always offered application and server desktop publishing with their XenApp product, which is a superset of Windows Terminal Services, which Citrix also wrote by the way. The value of this approach is that it takes far less hardware to service a given number of users, but they do give up some flexibility in the way the session operates. Our rule of thumb is to use XenApp where you can, and XenDesktop (VDI) for special cases. Most of our customers have about 80% XenApp users, and 20% VDI. The nice thing is that Whitehat and Citrix can offer you both options.