Here at Whitehat we occasionally get questions related to virtualization and the technologies we work with. The answers to those questions end up here on our blog for others to find that might have the same question.
Q: What is the difference between Citrix and VDI?
A: Citrix historically has been know as an application virtualization vendor, focusing on delivering applications to a multitude of edge devices from PCs to smart phones. Citrix does, however, have a handful of VDI offerings.
The longer answer…
VDI is the generic name for Virtual Desktops, or more specifically Virtual Desktop Infrastructure.
At a high level, suffice to say that a VDI desktop is a discrete desktop instance running on servers in the data center that an end user can access from anywhere they have access to the servers hosting the virtual desktops. Citrix and VMware are the two largest companies licensing VDI desktop technology.
Wikipedia has a different way of saying the same thing. “Desktop virtualization is software technology that separates the desktop environment and associated application software from the physical client device that is used to access it.”
VMware has a VDI offering which is named VMware Horizon View now on version 5.2. This includes a collection of additional features like VMware Thinapp, VMware vShield Endpoint, and Horizon View Persona Management.
Citrix had two VDI options available for sale. Citrix VDI-in-a-Box, formerly known as Kaviza, is Citrix’s entry level VDI solution. This solution is built on a grid architecture utilizing storage local to the server only. As capacity scales, you add more servers with a few caveats. Currently Citrix VDI-in-a-Box is on release 5.3 which now includes support for HDX connections to Windows 8 desktops, better 3D application support with the new H.264 SuperCodec and reduced bandwidth consumption. Certificate installation has been simplifed with a new wizard and suppot for Citrix’s Universal Print Driver has been included.
This solution is sold as a smaller, simpler, less expensive solution to XenDesktop primarily because there is no need for mass storage like a Storage Area Network (SAN) for the solution which (should) considerably reduce the overall cost of the solution.
Citrix has a second VDI solution in XenDesktop which works just as well in small environments as large ones but is certainly geared toward medium and large enterprise.
Citrix XenDesktop is available in four versions.
Citrix XenDesktop Versions:
XenDesktop Express – This version is available for up to 10 named users and includes the most basic of features in Citrix Receiver, Machine Creation Services and Desktop Studio.
XenDesktop VDI – This version licenses Citrix VDI technology without the more traditional Citrix products, XenApp (formerly Presentation Server, MetaFrame XP, MetaFrame 1.8, etc.)
XenDesktop Enterprise – This includes all of the features of XenDesktop VDI, plus Provisioning Services, and some additional features. The biggest benefit is the inclusion of Citrix’s flagship product XenApp which is folded into XenDesktop permanently with the release of Citrix XenDesktop 7. XenApp virtualizes applications, and is often used in tandem with XenDesktop to reduce individual user storage footprint.
XenDesktop Platinum – This version includes all of the features of the previous versions, plus an enhanced version of XenApp called XenApp Platinum, and a couple of additional features.
While there is a common definition of VDI, how virtual desktops are delivered do not follow a common methodology. VMware and Citrix both have their own unique protocols (PCoIP and HDX respectively or can use Microsoft’s RDP) for delivering discrete desktops from the data center.