Can MED-V take on Terminal Services?

Had a great conversation with an MMS 2010 attendee while I was helping man the Windows Manageability booth at the Expo Pavilion this week. We were discussing his existing applications, moving to Windows 7 and he asked “When is it appropriate to use MED-V, since I already have a legacy application on Terminal Services?”

Microsoft Enterprise Desktop Virtualization is a great way to manage the deployment of applications that will not run on Windows 7, but run on Windows XP. By providing a managed, virtual, integrated copy of Windows XP running inside Windows 7, users can still access a legacy application seamlessly from their desktop.

However, MED-V is not the ultimate solution to getting legacy applications to run on Windows 7 indefinitely. Its a way to get Windows 7 onto desktops without being held back by a specific application that is not yet ready to be upgraded, replaced or phased out of use.

But what if you already have the application available through Terminal Services? You may be running Citrix on Server 2003 Terminal Services. Or maybe the application will run on Vista and can be deployed using Server 2008 TS RemoteApp. Both those options are easier to manage than deploying and managing a host of extra virtual Windows XP machines on your network, especially if you already have an appropriate Terminal Services environment available.

MED-V is a tool to consider if you are Software Assurance customer, because access to the MDOP tools cost only about $7-8 per desktop. This can be cheaper than the cost of Terminal Service or Citrix CALs, unless of course, you already own those CALs.

MED-V and Terminal Services aren’t competing solutions for the same problem. But they can help you accomplish the same goal – getting your users working on Windows 7.

Inside MDOP: MED-V and App-V

Inside the Microsoft Desktop Optimization Pack, you’ll find MED-V and App-V. Both provide ways to deliver applications to your desktop, but they solve different problems.

MED-V is good for resolving incompatibilities between an application and Windows 7. By creating and distributing a full instance of Windows XP from which the application runs, users can access applications that would not run on Windows 7 otherwise. It’s also applicable for websites that must run in a browser like Internet Explorer 6. For example, an IE 6 instance can be launched from within the MED-V managed OS and be controlled with policies to limit the sites that are available from the less secure browser.

In general, a MED-V hosted application is isolated from the primary operating system, though the clipboard can be shared to allow for basic copy/paste functionality between applications and printer redirection can ensure users can print from the MED-V application. If your application is very task specific and does not require direct interactions with other applications on the primary operating system, MED-V can allow you to upgrade to Windows 7 before solving the application compatibility issue.

Application Virtualization (App-V) creates and delivers a single application in a package, instead of a full instance of an operating system like MED-V. The application package is cached on the local machine, but in not installed in the traditional sense. By not installing application files directly and keeping them isolated in their packages, App-V can eliminate conflicts between two applications that might otherwise cause failures when installed on the same machine. An example would be where Office 97 and later versions of Office share DLLs with similar names, but have functionality that doesn’t work with both products.

App-V also eases application upgrades and maintenance by allowing IT to update single packages that are then streamed to users on demand, instead of having to managing multiple local installations of software. Because applications deployed with App-V execute locally on the desktop they utilize the CPU and memory resources of the local machine instead of those on the server. Inter-application communication with other App-V applications and applications installed locally are preserved, allowing for cut and paste, OLE, and all other standard operations. However applications that install their own device driver, like a print driver, may not be suitable for complete virtualization.

In a nutshell, App-V can help you develop a more robust and controlled application management lifecycle, while allowing support for some legacy applications that don’t play well with new versions. MED-V builds a “temporary” bridge between applications that only work on older operating systems, providing some wiggle room so you can potentially upgrade your desktops without having to wait until all your applications are supported.

Depending on the needs of your organization, MED-V or App-V might be just what you need to solve a lingering application compatibility issue.