Microsoft Application Virtualization or App-V (fits in nicely within the *-V naming scheme, Hyper-V, MED-V...) is Microsoft’s application virtualization and application streaming technology that competes with the likes of Citrix XenApp streaming, VMware ThinApp or Symantec’s AppStream. Microsoft App-V was previously named Microsoft Softgrid which was acquired in July 06 through the acquisition of Softricity a Boston, Massachusetts software company.
Application Virtualization and streaming provides and enables the deployment of software into na isolated or sandboxed operating system environment without modifying the local OS file system or registry. This ensures operating system integrity, reduces application and DLL conflicts and reduces the need for application and environment testing on different hardware and operating system environments. Applications such as Office XP and Office 2007 can be sequenced then deployed and executed on the same end user device without any application conflicts.
Applications are profiled or sequenced (installed) usually on/to a dedicated workstation, these applications are as stated sequenced or packaged (think of this as the installation being monitored, looking for where files are installed to or registry entries are added) the binaries are bundled into a single file or .CAB and located somewhere accessible on the network (this is a highly simplified explanation!).
A sequenced application is then assigned to a user or group. Depending on how this application is assigned an icon is provided to the local desktop via the locally installed App-V client. When a user double clicks the icon the sequenced application is streamed to the local machine only downloading the parts of the applications required to execute into this isolated or sandboxed virtual environment on the local PC and executed. Often only 20-40% of an application is required to be downloaded before it can execute leading to improved start-up times. Downloaded binaries are cached on the local machine for faster retrieval when next required.
The network storage location provides a common set of binaries for all operation systems both desktop’s and server’s alike. If an admin needs to patch an application only the common source of binaries is patched/updated, the App-V client next requests this application the patched or changed binaries are automatically downloaded to the local machine and executed removing the requirements to visit each machine or deploy a patch through Active Directory, SCCM or your favourite deployment tool.
Microsoft provides a centralised management tool and core to App-V is the App-V management Web Service, this provides a central service for the admin of App-V servers and sequenced applications. Administrators communicate with the web service via the App-V Management Console through this console you can publish, assign, remove applications, configure settings, metering and permissions. The central management platform is not always required as Microsoft has provided alternative methods for deployment of streamed applications with a standalone mode, this allows the sequencer to package the virtual application into a MSI. This allows the delivery of sequenced applications to App-V desktops via the Microsoft Windows Installer with the Windows Installer loading and configuring the virtual applications. This in turn allows application delivery via your favourite ESD (Electronic Software Distribution) method or even from USB drive or CD/DVD.
While applications are retrieved from the network in real-time applications or end user devices can be configured for “offline” mode which allows the full application to be downloaded and cached on the local drive for full functionality offsite or while not connected to the network. Of course this is only possible when an application can function offsite or offline such as Adobe Reader or MS Office - don’t expect your SAP client to magically function without it’s backend database available!
At this time Microsoft only provide a 32bit (x86) client so this technology does not work on Vista x64 or Windows 2008 x64 however this is set to change in App-V 4.6 which is set to provide a x64 App-V client.
Not all applications are candidates for application virtualization and each IT professionals experiences with application virtualization are different. Some applications just plan refuse to sequence while applications such as MS Office may best be installed locally in the traditional manner to ensure all application can access Office outside of its sandbox. My only recommendations to you is test, test and then test again. With App-V 4.5 some say you can even virtualize windows services, however I have no such experience.
Microsoft Application Virtualization for Terminal Services or App-V for TS is the version of App-V that runs under Terminal Services (Remote Desktop Services) or Citrix XenApp (just to confuse) and extends its capabilities to profile management (among others) allowing the use of things such as mandatory profiles with the ability to capture user settings and configuration data and in turn saving this data to the network. This delivers a dynamic yet locked down profile that saves all user settings while providing all the stability benefits of mandatory profiles in Terminal Services environments. (Anyone remember flex profiles!)
Currently App-V is available via the Microsoft Desktop Optimization Pack (MDOP) to SA covered desktops for the cool price of $10 per end user device.
The following PDF while a little dated now with the new releases of referenced software versions still provides a good comparison of competing application virtualization products.
Microsoft’s App-V site.
Microsoft App-V for Terminal Services.
Excellent community App-V blog.