New desktop virtualization scheme will enable hybrid Windows deployment

Just one month after its acquisition of a partner company called Kidaro, which produced desktop virtualization software, Microsoft yesterday announced the immediate availability of a greatly enhanced version of its own desktop virtualization package for its volume license customers. As part of its latest update to Desktop Optimization Pack (MDOP), Microsoft's new Enterprise Desktop Virtualization software (MED-V) will let companies deploy software running in older versions of Windows, to appear on clients running newer versions such as Vista.

What this means is, software that ran fairly well in Windows XP or Windows 2000, and Web-driven software that runs using Internet Explorer 6 but not IE7 or IE8, can now run in a virtual envelope that leverages Virtual PC. Meanwhile, clients' users won't notice anything unusual; legacy apps' icons will appear on clients' desktops as though they were installed on their local systems.

"MED-V builds on top of Microsoft Virtual PC to run two operating systems on one device, adding virtual image delivery, policy-based provisioning and centralized management," reads a blog post yesterday from the MDOP team's Ran Oelgiesser.

Now, application virtualization is nothing new for Microsoft; two years ago, its acquisition of SoftGrid enabled server-driven apps to appear as though they were installed on the client, including apps for older Windows. What MED-V adds to the picture is a way for virtual envelopes to host legacy apps either way: through the server or through the client, whichever happens to be most convenient at the time. The management software -- part of the latest Kidaro acquisition -- introduces a centralized platform for software management, so even the applications running within the envelope can be governed by policies administered outside the envelope.

Under the architecture of the new system, a central server governs all the images of virtual systems -- "partial desktops," if you will, that run in virtual envelopes. Those images are then distributed in whole or in part through Internet Information Server, depending on whether those images are to be run on the client or through the server, respectively. The client user only sees the products of the virtual image integrated with his regular desktop.

Besides MSDN and TechNet subscribers, MED-V will be available only as part of MDOP, and only through Microsoft's volume licensing service. The terms of those licenses had to be adjusted last week, easing some restrictions so that customers running older OS platforms under virtualization don't have to get charged for those older systems all over again.