app virtualization (application virtualization)
What is app virtualization?
App virtualization (application virtualization) is the separation of an installation of an application from the client computer accessing it.
From the user's perspective, the application works just like it would if it lived on the user's device. The user can move or resize the application window as well as carry out keyboard and mouse operations. There might be subtle differences at times, but for the most part, the user should have a seamless experience.
How application virtualization works
Although there are multiple ways to virtualize applications, IT teams often take a server-based approach, delivering the applications without having to install them on individual desktops. Instead, administrators implement remote applications on a server in the organization's data center or with a hosting service and then deliver them to the users' desktops.
To make this possible, IT must use an application virtualization product. Application virtualization vendors and their products include Microsoft App-V; Citrix Virtual Apps; Parallels Remote Application Server; and VMware ThinApp or App Volumes, both of which are included with VMware Horizon. VMware also offers Horizon Apps to further support app virtualization.
The application virtualization software essentially transmits the application as individual pixels from the hosting server to the desktops using a remote display protocol such as Microsoft's Remote Desktop Protocol, Citrix HDX, VMware Blast Extreme or PC over IP. The user can then access and use the app as though it were installed locally. Any user actions are transmitted back to the server, which carries them out.
Benefits of app virtualization
App virtualization can be an effective way for organizations to implement and maintain their desktop applications. One of the benefits of application virtualization is that administrators only need to install an app once to a centralized server rather than to multiple desktops. This also makes it simpler to update applications and roll out patches.
In addition, administrators have an easier time controlling application access. For example, if a user should no longer have access an application, the administrator can deny access permissions to the application without uninstalling it from the user's desktop.
App virtualization technology makes it possible to run applications that might conflict with a user's desktop applications or with other virtualized applications.
Users can also access virtualized applications from thin clients, or non-Windows computers. The applications are immediately available without requiring users to wait for long install or load operations. If a computer is lost or stolen, sensitive application data stays on the server and does not get compromised.
Drawbacks of app virtualization
Application virtualization does have its challenges, however. Not all applications are suited to virtualization. Graphics-intensive applications, for example, can get bogged down in the rendering process. In addition, users require a steady and reliable connection to the server to use the applications.
The use of peripheral devices can get more complicated with app virtualization, especially when it comes to printing. System monitoring products can also have trouble with virtualized applications, making it difficult to troubleshoot and isolate performance issues.
What about streaming applications?
With application streaming, the virtualized application runs on the end user's local computer. When a user requests an application, the local computer downloads its components on demand. Only certain parts of an application are required to launch the app; the remainder download in the background as needed.
Once completely downloaded, a streamed application can function without a network connection. Various models and degrees of isolation ensure streaming applications do not interfere with other applications and can be cleanly removed when the user closes the application.
