Desktop virtualization has its own infrastructure needs
Server virtualization is well established at most agencies, and the next step for many is at the desktop. But virtualizing desktop images and applications is a different animal and it has its own infrastructure needs, so getting the answers to those right is key to success.
Although the focus of all agencies in the past several years has been on server virtualization and consolidation, virtual desktop infrastructure (VDI) has been seen as an obvious next step. For various reasons — lack of funds, doubts about security, concerns about increased complexity — VDI has not taken off as quickly as many assumed it would, though the need for cost savings and tangential trends such as bring your own device and teleworking are pushing it to the fore again.
In its survey of government IT professionals, MeriTalk found that a quarter of all federal agencies had plans to virtualize at least some of their applications, though only a small number expected to virtualize all applications for all their users. It also pointed out that, if VDI garners just half of the savings expected from server virtualization, agencies could cut nearly 10 percent from their IT budgets.
Cost is a big reason for the Census Bureau to go with VDI, both to minimize the cost of endpoint computing by using zero or thin clients and to centrally manage such things as maintaining and patching software, an expensive process at organizations with hundreds or thousands of individual desktop PCs.
Ironically, given the general doubts about security, Census CIO Brian McGrath believes another huge benefit of VDI is the boost it provides to security, particularly for the dispersed and mobile workforce the bureau employs.
“With VDI, we are providing the applications and data out of a private cloud, so the only thing the user sees is really just light that’s being pushed down the wire,” he said. “Since there’s no opportunity to store data on the endpoint, that ensures the security of that data and the applications.”
Security is also enhanced by providing the ability to remotely kill an image on a mobile device, said Adrian Gardner, CIO at NASA’s Goddard Space Flight Center. He is looking to VDI to improve the way scientists at the center can collaborate with the many visiting scientists and students who contribute to NASA’s mission and who want to use their own devices to do so.
The biggest potential problem that affects performance with VDI is network latency, said Christopher Fudge, Census’ virtual infrastructure branch chief. Some of that is out of the bureau’s hands — if a worker in the Midwest can’t get a good mobile connection, for example — but some of the issues can be handled internally. Although not aimed wholly at VDI, Census has at the same time modernized its compute platform, rationalized its storage environment and upgraded its internal network capabilities to 10 gigabits/sec speeds as a part of an overall IT infrastructure transformation.
It’s a big mistake for an organization to assume that if it’s done server virtualization, then it knows what’s needed for desktop virtualization, said Jose Padin, systems engineer manager at Citrix Systems.
“Server and desktop have a hypervisor in common and not much more,” he said. “With server virtualization, it’s a server providing a service that users access through a browser, and they don’t generally have to log on to the server. With desktop virtualization, the desktop Windows operating system is running on the back-end infrastructure and being remotely controlled, and because of that the requirements for RAM, CPU and storage are vastly different.”
Also, he said, although VDI has obvious advantages for supporting the increasing numbers and kinds of devices being used in organizations today, there are other ways to virtualize the desktop, such as sharing a single operating system running on a server with many different users, something that could be used as a stepping-stone to full VDI. The key is knowing what users are actually doing in their daily business and what their specific requirements are.
That also points to the network latency issues that will crop up. You can’t assume that desktop virtualization will only run in large-bandwidth and low-latency scenarios, he said, so you have to plan for situations where you won’t have those things to deliver a truly great virtual desktop solution.