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Often organizations don't really need to deliver full virtual desktops to employees to allow them to work remotely. Citrix XenApp 7.6 and VMware Horizon 6.1 each offer the ability to deliver individual virtualized applications, giving administrators a pair of good options to choose from.
Application publishing can be useful for delivering virtual apps to desktops, but it's really picked up momentum with the proliferation of mobile devices in the workplace. XenApp 7.6 and Horizon 6.1 give desktop virtualization administrators a secure way to provide employees with applications on their smartphone or tablet using Remote Desktop Session Host (RDSH) servers in the data center.
RDSH is part of Microsoft's Remote Desktop Services, which allows IT to provide remote access to virtual desktops and Windows applications using Windows Server. Admins can deliver those desktops or apps to a range of client devices, from PCs, thin clients, zero clients or even HTML5 clients. But Citrix has a longer history with RDSH applications than VMware, and its XenApp product is widely considered the industry leader in app virtualization and publishing. As applications gained importance in the enterprise over the past few years, VMware wised up and now appears just as serious about app delivery.
Citrix XenApp leads the way
Despite recent tumult -- the company merged XenApp with XenDesktop, then brought back a new standalone version -- XenApp has a lot going for it, including centralized control over virtual app delivery.
XenApp can deliver apps hosted on either Windows or Linux operating systems, and it can even run Windows and Linux desktops side by side in the cloud. Admins can enforce granular access policies for virtual apps and desktops, which helps mitigate the risk of exposing corporate data on unsecure connections. Companies can also secure access to apps using Citrix NetScaler, which serves as an application delivery controller, load balancer, virtual private network and application firewall that connects the back-end technology to end users. Workers access their virtual applications using Citrix Receiver, a universal client that runs on Apple iOS and Google Android devices, along with Windows, Mac and Linux computers.
XenApp includes several handy features that Horizon 6 RDSH does not, such as support for microphones and webcams, and integration with the Citrix X1 Bluetooth mouse, which makes it easier for iOS users to use remote Windows applications. But VMware has caught up in recent updates to Horizon 6, adding features such as printing, which were previously only available with XenApp.
The biggest recent change to XenApp came when Citrix transitioned from version 6.5 to XenApp 7.5. Citrix switched XenApp from an IMA platform to an FMA platform, which is what XenDesktop runs on, so it increased the integration between the two products and between Citrix VDI and RDSH. XenApp 7.5 also added hybrid cloud provisioning, which makes it possible to deliver virtual apps through the cloud.
Finally, XenApp has been around a lot longer than Horizon 6, and it integrates better with other virtualization products. Horizon 6 RDSH apps have to run through VMware vSphere, whereas XenApp integrates with outside platforms such as vSphere, Microsoft Hyper-V and Amazon Web Services.
VMware Horizon 6 RDSH is catching up
Citrix ended up bringing back XenApp in 2014, but in the meantime VMware seized the opportunity to elbow its way into the app remoting market with Horizon 6.
Application publishing with Horizon 6 requires a group of Windows Servers with the same configuration, also called an RDSH farm. Admins publish applications on the RDSH servers and can deliver them with full virtual desktops or independently using RDSH application pools, which link to the farms through an executable. To ensure window management and other services, admins have to use the View Unity Shell. End users can access published applications through the Horizon Workspace or Horizon View client, which are simple to navigate, where they can resize or move the apps around.
VMware added new features for RDSH in Horizon 6.1 and 6.2, including support for single-user RDSH desktops. It also added support for USB redirection, which allows users to access files on their remote apps and access published apps through HTML5 browser clients. Additionally, Horizon 6.1 supports Nvidia GRID virtual GPU technology and Smart Card authentication. Those features were previously only available for VDI, which shows VMware's interest in getting its RDSH support up to speed. XenApp 7.6 offers roughly the same features, but Horizon 6.2 leveled the playing field a little.
Still, there's a major gap in VMware's Horizon 6 RDSH. The View Persona Management tool does not fully support RDSH app publishing, which means companies may need to invest in another profile management product to ensure that users' settings transfer over from login to login. This is a notable difference from Citrix's User Profile Management tool, which works seamlessly across XenDesktop and XenApp.
VMware does offer a pair of other app virtualization tools -- ThinApp and App Volumes -- although they use different technology than Horizon 6 RDSH to deliver virtual apps. ThinApp and App Volumes are both app layering products. ThinApp places virtual applications in an isolated bubble, which can help with compatibility issues, and App Volumes runs apps in a container on top of the host operating system.
Horizon 6 RDSH app publishing is certainly now a reputable option, especially for VMware shops, but it still lags slightly behind Citrix's offering. Even if Citrix confused some customers with its XenApp runaround over the past few years, it still has the top app remoting product on the market. That said, the gap between Citrix and VMware's app publishing products continues to shrink.
A guide to using Horizon 6 RDSH
How Horizon 6 RDSH works and what it's missing
VMware is catching up to Citrix on VDI