Citrix Systems is buying a young and aggressive desktop virtualization startup, RingCube Technologies, for an undisclosed amount, the company announced Wednesday.

RingCube's vDisk capabilities will be added to Citrix' XenDesktop product set. When they are integrated–no timeline announced as yet--Citrix will have another distinguishing capability in the desktop virtualization marketplace.

Citrix is the leader in the desktop virtualization market, although the market has been slow to develop due to its complexity and the potential of user backlash against newly instituted virtual desktops. VMware, with VMware View, and a number of spot solutions, such as MokaFive, Wanova, and Virtual Computer compete with Citrix in the space.

RingCube had its coming out party during the 2006 Demo Show, when CTO Mike Larkin tripped as he stepped onto the stage in San Diego. The move caused the laptop he was carrying to crash to the floor and the Demo screens to go dark. Then he pulled an iPod out of his pocket and reloaded a virtual desktop on a nearby machine to pick up where he had left off. The stunt demonstrated that a user's personal computer workspace could be stored as a file on any digital memory device and be reactivated as a virtual machine.

RingCube stored the virtual desktop on a memory device that it called its Mojopac. That virtual desktop file could then be uploaded to run with its usual applications and identifying characteristics, while piggybacking on top of the local Windows operating system. Citrix will adopt some of the tricks that RingCube has pioneered to offer a more flexible way to distribute virtual desktops in its own product line.

John Fanelli, VP of enterprise desktops and applications at Citrix, said that in the past, implementers of virtual desktops have been forced to choose between highly individualized desktops that are each stored, incurring high storage costs, or highly standardized pooled desktops, where one size fits all.

The idea is to marry IT control and administration from central servers with accommodation of individual preferences. With the RingCube acquisition, Fanelli said Citrix will be able to offer more flexibility in a virtual desktop infrastructure than in the past. It will be based on what RingCube calls a personal vDisk, which will isolate and store only the unique parts of each individual's virtualized desktop. The parts used in common will exist as one shared copy in the data center, running on central servers capable of handling many end users at a time.

With RingCube, Fanelli said in a telephone press conference Wednesday, personalized settings and applications can be stored, then combined with a pooled copy of the operating system when the desktop is activated. Such a move eliminates the need to store slightly varied versions of Windows with many different desktops. Each user's desktop runs on a server in the data center, with interactions taking place between an end user client and server over the local area network.

Call centers or customer contact units often work from highly standardized applications amenable to a one-size-fits all virtualized desktop based on one copy of the Windows operating system. But individual power users often have a list of personal applications they want to keep on their machines, and personalized settings and configurations for the operating system. This group can also be accommodated, Fanelli said.

In response to a question from InformationWeek, he said individual IT departments will be able to decide how much of the desktop they wish to build from pooled parts and which applications they wish to offer only as virtualized services from central servers, such as Microsoft Outlook email and Office apps. Applications used only by individuals or small groups would be stored on the user's vDisk.

The approach makes it easier to move from physical desktops to virtual desktops, Fanelli claimed, because the vDisk approach makes the change relatively transparent to end users. At the same time, IT gains more centralized, end user desktop administration.

End users may be given the option of installing additional personalized applications, including non-business ones, on their vDisk and having them available, if a company policy decides to allow such a move, he said.

Citrix was an early leader in end user virtualization when it centralized Windows applications on data center servers and offered them to hundreds or thousands of end users at a time through its Presentation Manager centralized server. Oracle, HP, Wyse, and other major parties have jumped into end user virtualization. But Fanelli said market researcher IDC, in a designation earlier this year, said the "Desktop Virtualization Marketspace" had a single leader, Citrix. It listed VMware, MokaFive, and Kaviza as major players as well.

In May, Citrix purchased Kaviza, supplier of a Citrix virtual desktop infrastructure environment "in a box" for ease of installation by small business.

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