You don’t need XenDesktop for a virtual desktop

Author: Ingmar Verheij

XenDesktop 7For years Citrix has a product to host applications from a centralized locations offering great flexibility and efficiency, called Citrix XenApp. In 2008 Citrix released XenDesktop, the VDI solution from Citrix. With this first release of XenDesktop it was possible to (only) publish a desktop hosted on a single user operating system (like Windows XP, Vista or 7).

Citrix has tried to choose an appropriate name for their products to help customers understand what product offers what solution (and reducing the ridiculous times they rename their products). Although this is an admirable attempt they failed to reach that goal.

A lot of customer assume that with XenApp they can (only) publish applications and with XenDesktop (only) desktops, how wrong can they be?

Customers are confused

Customers confuse functionality, terminology with product branding (and marketing). A functionality like virtual desktops can be offered by both XenApp and XenDesktop, customers assume they need XenDesktop. When an application cannot be hosted on a multi-user platform (or has strict requirements) they know there’s an alternative: hosting the application on a Windows 7 (XP is history) machine via XenDesktop. Again the assumption is made they need to publish a desktop to the user, not just the application hosted on that machine.

The result of mixing up functionality, terminology and products is that customers has requested the wrong solution to their IT department or (worse) implementation partner. In some cases the IT department or implementation partner succeeded in explaining the technologies resulting in proper requirements and a successful implementation. In other cases a “VDI” project is started, some projects actually implemented and in some (rare) cases implemented successfully. I’ve seen customers that has a successfully implemented virtual desktops with Citrix XenDesktop, but ended up hosting 20 different desktops. Each desktop hosted a different set of applications, managing the environment becomes cumbersome.



Get functionality, terminology and products right

Terminology got mixed up because both vendors and community initially did not understand the impact and possibilities of the products that were developed in the years that followed.

When a user connects to a “virtual desktop” he accesses an execution platform that is different than the where is keyboard and screen is connected to. A virtual desktop infrastructure (or VDI) is nothing more than a collection of components that enable the user to connect to this “virtual desktop” with a remoting protocol (like Microsoft RDP, Citrix ICA, etc.).

A virtual desktop can be hosted on a multi-user system (Citrix XenApp) or a single-user system (Citrix XenDesktop or RemotePC). The same applies for applications, applications can be published seamless (!) on a multi-user system (Citrix XenApp) or a single-user system (Citrix XenDesktop) . Most customers (and implementation partners) are not aware of the ability to publish applications seamless from a single-user system with Citrix XenDesktop with VM Hosted applications.

A virtual desktop on a multi-user system (XenApp) is called a hosted shared desktop  and a virtual desktop on a single-user system (XenDesktop) is called a hosted virtual desktop.




Citrix FlexCastAlthough I’m not a fan of marketing terminology like FlexCast I do believe the hit the nail right on the head. With FlexCast Citrix offers a platform to mix and match resources published from different sources seamlessly to the user, meaning user can connect to applications and desktops without knowing where they are hosted.

I strongly believe a user should not be aware of what technology is used, it should application to do its job. For that it needs one desktop to hold its shortcuts to applications, no more. Wetter that desktop is on its physical machine (desktop or laptop) or somewhere in the datacenter that should not matter, but don’t plague them with a bunch of desktops.


To conclude

The difference between XenApp and XenDesktop is not application vs. desktop but multi-user vs. single-user systems.

A “virtual desktop“ can be offered on a multi-user system with XenApp and a single-user system system with XenDesktop.

Do you have a “special” application that needs :

  • single-user machine;
  • administrative privileges,;
  • 3D graphics;
  • is selfish with resources (consumes all resource can take) ;
  • require a 1-on-1 relation between user and machine (for instance for functional accounts);
  • etc.

than publish the application on a desktop operating system (Windows 7, Windows 8) with VM Hosted Apps using XenDesktop, not the desktop Knipogende emoticon


What’s coming

Project AvalonThe customers I speak to are not unique, Citrix has a lot of customers that face the challenges. Fortunately Citrix is aware of this currently developing a new product, currently under the name “Project Excalibur” which is part of “Project Avalon”. This product integrates XenApp, XenDesktop and more existing products in one product. Published resources (applications or desktop) on a single- or multi-user system are no longer bound to a product (XenApp or XenDesktop), it’s configurable for each published resource! Not only will “Project Excalibur” provide a lot of integration between the a lot of products, it could help customer rethink their requirements and do a proper implementation.

Project ExcaliburThe name for this product has yet to be revealed, but it is expected that the name of this product will replace either XenApp of XenDesktop. Although XenApp is well known in the market it is unlikely Citrix will abandon their XenDesktop name, it could very well be that “Project Excalibur” will be the new release of Citrix XenDesktop and XenApp is history.

Hopefully Citrix has read my article about “Citrix and the curse of version 6” and skips version 6 for XenDesktop, which would make sense since XenApp currently is version 6.5.

So next year we’ll have a XenDesktop 7? Only time will tell.