Gartner: Microsoft Must Embrace Virtualized OS After Vista

deliver updates on a more frequent schedule

"The sale of new operating systems has to start coming in more closely-defined periods," said Brian Gammage, a Gartner vice president and resident expert on virtualization. "The way to do this is with modules."

Microsoft's mistakes in Vista's development have been well-chronicled, and the company's leaders recognize that another five-year gap between major updates of their money maker could be disastrous. In July, chief executive Steve Ballmer told financial analysts "we will never repeat our experience with Windows Vista, we will never have a five-year gap between major releases of flagship products."

But exactly how will Microsoft do this? How can it handle the increasingly unwieldy amount of code in Windows, better secure the operating system, and maintain backward compatibility with the legions of legacy applications? Gartner's Gammage and two colleagues, Michael Silver and David Mitchell Smith, believe they know.

"Microsoft will have to move toward virtualization at its core to change direction," said Gammage. "We think this is what will happen. Microsoft, at the moment, disagrees with us.

"But we don't see another way of doing this."

In the scheme that Gammage sees playing out, Microsoft will be forced into adding a "hypervisor," a layer of virtualization software that runs between the operating system and hardware, to Vista by no later than 2009. Virtualization-enabled processors and chipsets, such as the newer offerings from both Intel and AMD, allow hypervisors to run, which in turn let developers separate functions of an OS into chunks, then have those pieces run simultaneously in multiple virtual machine partitions.

"We expect this hypervisor to provide the key enabling technology for reversing the trend in functional integration," wrote Gammage, Silver, and Smith in a research report they issued nearly two weeks ago.

"This is how Microsoft will be able to deal with 25 years of backward compatibility," Gammage said. Virtualization, he said will allow a future Windows to run the legacy kernel -- to support aged applications -- alongside a new kernel, just as current virtual machine technologies let users run different operating systems side-by-side.

"It's not possible for Microsoft to do what Apple's done," said Gammage, referring to Apple Computer's two moves in the last decade -- one to Mac OS X, the other to Intel processors -- that have abandoned an older operating system, and thus some of its applications. "Apple has a much smaller installed base, and a lot of user satisfaction and goodwill that Microsoft doesn't. Apple has a much different client constituency that has accepted these changes. Microsoft's wouldn't."

An OS-integrated hypervisor and virtualization may also solve security problems that are introduced each time Microsoft rewrites the operating system, and expands its code. By building future versions of Windows from smaller modules that sit atop mature code -- mature in that it's been real-world tested by attacks and those holes patched -- the Redmond, Wash. developer might be able to construct more reliable releases. And by separating old code and applications from the new in separate virtual partitions, future Windows can protect itself from the vulnerabilities attackers now exploit.

Gartner's Gammage is convinced that Vista is the last major release of Windows built on what he called a "monolithic architecture." In fact, the release of Vista makes the next few years a perfect opportunity for Microsoft to switch gears.

Because Microsoft has alternated major and minor Windows upgrades -- Windows 2000, which was major, led to the minor Windows XP, which in turn led to the major Vista -- "this is the junction when they have the opportunity to go off in another direction," said Gammage.

Gammage believes that Microsoft will have to move to make Windows more modular by 2008, and embrace a hypervisor in a minor update to Vista (or even a Vista Service Pack) in the 2008-09 timeframe. By 2010, it could deliver the follow-on to Vista -- Gartner dubs it Windows NG, for Next Generation -- in two virtualized partitions: one dedicated to system management and security functions, and the other to user applications.

"Microsoft disagrees with this vision for its client OS," Gammage said. Instead, Microsoft, which at one point in the development of Vista thought virtualization was the answer, believes its current approach of building Windows into a stack of more than 50 layers -- in which the ones below are not dependent on those above -- is the answer. "They think the layered approach is going to help them set themselves up for faster product cycles. But we don't see any assurance of that."

In the end, Gammage expects Microsoft to see the light.

"They have to do this, if only because of the resources they're dedicating to maintaining the product in its current form."