Citrix Local App Access Eliminates Double-Hop HDX

One of the new features of XenDesktop 7 and XenApp 6.5 Feature Pack is Local App Access, a technology you might be familiar with under the name "reverse seamless" that RES Software has had in its software for some time now. My understanding is that Citrix and RES have to come to some kind of arrangement that satisfies the legal issues. That being said, it is worth mentioning that Citrix Local App Access is an application that was created from the ground up by Citrix developers -- no code was leveraged from the RES Software implementation.

For those of you that are not familiar with this technology, Local App Access is quite interesting in that it allows applications that are installed on the end point to be available within your VDI or XenApp session seamlessly. Since these apps are simply being channeled into the sessions, no server-side resources are consumed at all.

You might be wondering where this could be helpful or useful. For starters, my interest in local app access is that it eliminates double-hop scenarios with HDX. Today, when you deploy XenApp applications into a XenDesktop VDI session and launch those apps, you are initiating a new HDX session from your VDI desktop to that application. But remember, you already have an HDX session to your VDI, so you end up having an HDX session within an HDX session. It performs well, but imagine if we could eliminate that second hop. So, how do you do this?

Well Citrix Receiver is installed on your end point, which is required to launch a XenDesktop VDI, right? So why can’t I launch XenApp applications directly from the end points and then use Local App Access to inject the app into the VDI session? You will, of course, have two HDX sessions to the end point, but you no longer have a session within a session. As a result your performance will be significantly enhanced.

Another good use case for Local App Access is where you might need to run apps that still do not work in a virtual environment or are not supported. You can then channel the app and inject it via Local App Access, thereby making it seamless and less confusing for the user; that way, users won't have to leave the VDI session to launch any other application.

Consider local devices on the end point as well, like DVD drives or other peripherals that can now also be accessed from within the VDI session. Or take it one step further with applications like WebEx or GoToMeeting, which can also be leveraged with some of their bandwidth-intensive requirements, especially if you are using video conferencing. While the new HDX does a great job with video, local app access might be an option. Finally, another option is for employees or users that bring their own devices and be able to use their local applications within the session without compromising policy or security that you have established. A good example here is iTunes, an application that you would typically not allow on your desktops. Now, user can use it if it is installed on their local machine.

I am interested in hearing about some scenarios where Local App Access could be useful in your environments.

Posted by Elias Khnaser on 06/19/2013 at 1:26 PM