How to Overcome VDI Limitations with Virtual Workspaces

By Kiran Kamity
published: Friday, June 19 2009

If you have a VDI deployment, you've probably realized by now that although it is deployable for a task worker who is always connected to the LAN, it does have serious limitations that make it difficult to scale to power users, remote users and the rest of your enterprise. Some of the common VDI pain points that IT administrators continue to raise concerns over include:

• How do I support user installed applications in my VDI environment without dedicating one VM per user (i.e. without increasing cost and management complexity)?

• How do I better manage and provision specific apps (e.g. VoIP clients, VPN clients, SQL-based apps, PDF printing apps) when application virtualization technologies like ThinApp or App-V do not work?

• How do I enable VDI users to go offline without having to completely checkout a full copy of the OS?

• Is there another way I can ensure high availability of my virtual desktops without replicating all of my virtual servers?

• Is there a better fail-over mechanism available if my connection broker goes down?

• How can I get voice and video intensive applications to perform better with virtual desktops?

• How can I better support printers and USB devices in a virtual desktop environment?

If viewed separately, each of these problems would need a solution that is independent from the other causing increased complexity. Some IT groups are waiting for VDI vendors to solve these problems within their roadmaps, which is obviously causing delays in their deployments. And other large organizations are forced to build custom solutions which are both costly and difficult to support.

Fortunately, there is an architecturally elegant approach for solving the majority of these problems that involves a combination of two virtualization technologies - VDI and Workspace Virtualization.

This article discusses how these two types of virtual desktop technologies, when properly combined, can solve these problems

What is Workspace Virtualization?

Here's how Gartner defines Workspace Virtualization - "Workspace Virtualization is an emerging technology category, which decouples the user's workspace - applications, data and personalized settings - from the underlying operating system, simplifying the creation, provisioning and management of end-user computing environments which are mobile and can be customized by the end-user without requiring a second operating system."

In addition to this decoupling layer between the operating system and the applications, data, and settings, workspace virtualization also has significant performance advantages over hypervisor-based approaches. Since virtual workspaces do not involve hardware virtualization or emulation, applications in a virtual workspace run close to the speed of applications in the native host computer (i.e. typically less than 1% of performance overhead).

How does this all work?

The figure above demonstrates how a workspace virtualization technology integrates with VDI. The VDI infrastructure enables the end user to login to a VM in the non-persistent pool using a screen scraping technology like RDP or ICA. The VMs in the pool simply have the plain vanilla OS. The user's actual workspace, comprised of applications, data and settings, is managed by the workspace virtualization technology.

When user Joe logs into his VDI setup, let us assume the connection broker assigns him VM1 from the non-persistent pool. Joe's virtual workspace is automatically launched in VM1. The next time Joe logs in, if the connection broker assigns him VM5 from the pool, Joe's virtual workspace is launched in VM5. So no matter which VM Joe is assigned to by the connection broker, he always logs into his virtual workspace.