Client Virtualization: The Next Frontier

How to improve laptop management and the benefits of hosted virtual desktops.

by Martin Ingram

To date, virtualization has been mostly a data center technology; both server consolidation and desktop virtualization have been targeted at centrally hosted solutions. However, this is all about to change as client virtualization will bring about a very significant change in the way computing is delivered to end users.

Virtualization is having a huge impact on how organizations think about managing PCs, but has not addressed perhaps the biggest need in terms of the most expensive platform to manage in the enterprise – laptops. In addition to having many of the same challenges of traditional desktops, laptops often have to work outside the firewall and are frequently disconnected from the corporate LAN for long periods of time. Laptop users are routinely made administrators of their personal machines -- a recipe for an expensive and difficult to manage platform. In addition, laptop use has increased exponentially in the enterprise and is now approaching 50 percent of the user base.

Before we examine how to improve the management of laptops, we must understand the benefits of hosted virtual desktops. Historically, the PC has not been a well-managed platform. Organizations spend time and money maintaining traditional PCs -- a platform that was not designed to be managed.

There are three basic types of data in the PC’s software image: operating system (OS), applications, and user environment. The OS has been the defining element of the PC in the past, but in today’s local, hosted, and virtualized world of composite systems, it is losing some of its importance. Applications are where the real work is done and can now be delivered in many ways, such as traditional installs, virtualization, and hosted applications. Lastly, there is the user environment which contains everything associated with the user and represents the uniqueness in the system.

What has made the traditional PC extremely difficult to manage is that all three parts are blended together so that it is impossible to change any one part without risking changes to another. What virtualization allows us to do is to keep each of these elements separate, so we can use an appropriate tool to manage each type of data.

For OSes, the right tool means delivering the right OS at the current patch level. Applications, on the other hand, need to be delivered by the most appropriate means and at the correct version. The user environment needs to be applied to both the applications and the OS to give users a familiar and productive working environment. It also should be able to configure the standardized applications and OS to fit that specific business user. Managing the user environment is the way that desktop virtualization delivers maximum benefits to the organization.

In practice, many organizations are adopting these technologies in a pragmatic way; some starting with OS virtualization, others starting with application or user virtualization. However, the key is that everyone is working towards the goal of managing each of the components in the most appropriate way.

How does this help us with our laptop estates? The objective of managing each of the components in the most appropriate way still applies, and both user virtualization and application virtualization products typically support off-line use. The missing piece of the puzzle has been the ability to virtualize the OS on laptops. In 2010 we will see the first offering from Citrix and possibly VMware to provide a hypervisor for laptops that will allow the virtualization and management of client OSs on laptops.

This event is going to be extremely significant because there are a number of challenges, specific to laptops, that need to be addressed in order to make this technology successful. Partly this is a result of laptops not always being connected to the corporate network and partly because of the variances between laptop models.

Although servers have very few variations in their hardware and, hence, in the drivers needed to support that hardware, the opposite is the case for laptops. Even within a particular model run you can find that hardware components will change. Across a typical enterprise you will usually find many differing models, all with different driver requirements. This did not matter with a fixed OS per machine, but as we move to treating the OS as a standardized component across the business, we do not want to support all the hardware variants in that single image. In other words, the hardware variances need to be abstracted. This is the other key role for the hypervisor -- to abstract drivers out of the OS in order to standardize it.

In essence, the client hypervisor creates a well-defined boundary between the hardware and the OS that allows us to hide hardware variations and easily replace the client OS. Of course, that does not prevent us from running more than one OS on the client. In fact, some security vendors are planning to move some security capabilities out of the primary OS into a self-contained and better-protected virtual machine on its own.

For some use cases it will make sense to provision the machine with multiple client OSs with different security policies. These might be a locked-down corporate image and a more lax personal image, but the concern is that users will find this split model of working difficult to handle.

With the arrival of the first product from the major vendors, we will have our first opportunities to validate the ability of client hypervisors to hide machine variance. Perhaps what will be more significant is the opportunity to build out our management models to understand how OS, application, and user virtualization can be used together to manage laptops.

Desktop virtualization has revolutionized the way we think about managing desktops inside the business by allowing us to manage each of the components of the desktop image in the most effective way. This year we will start to see the move to virtualization for laptops. The key to this will be a management model that leverages the success of hosted virtual desktops to deal with this most challenging of platforms.

Martin Ingram is the vice president of strategy at AppSense. You can contact the author at