In-Depth

Microsoft Reveals Its Virtualization Vision

VMware might be far out in front, but don't count Microsoft out.

• By Stephen Swoyer
• 01/27/2008

Last week, however, Microsoft sounded like an unambiguous proponent of virtualization, touting its acquisition of Calista Technologies (which it says should improve the end-user experience for virtualized desktops and applications), along with its expanded alliance with Citrix Systems Inc., among other virtualization-friendly developments.

Elsewhere, the company announced virtualization-friendly licensing options for its Windows Vista operating system (i.e., virtualization support for both Vista Home Basic and Vista Home Premium), price cuts for large-scale Windows virtualization adopters, and new tools to help speed the deployment of Microsoft's virtualization software.

Redmond also outlined its own virtualization vision, touting a new strategy -- which it calls Dynamic IT -- which the company claims can deliver an efficient, flexible, resilient, and cost-effective computing environment.

Not a bad move for a company that sometimes sounds like a curiously reluctant proponent of virtualization.

A Very Big Deal for Microsoft

Last week's summit was a Very Big Deal for Microsoft, according to industry veteran Charles King, a principal with consultancy Pund-IT. Microsoft's fitful interest in virtualization parallels (and is, in a sense, proportionate to) the threat that the technology poses to its Windows operating system juggernaut. To the extent that virtualization abstracts everything -- even the operating system itself -- it's a threat to Microsoft's Windows cash cow.

"Two issues heightened interest in Microsoft's Virtualization Deployment Summit: the exploding interest in x86 virtualization technologies and the anticipation of a coming horse race between Microsoft and virtualization market leader VMware," he points out.

"To its credit, Microsoft mostly kept things on the up and up, though there were occasional snipes about the cost and complexity of competing products [i.e., from VMware]," King says. "[Microsoft] focused on what it sees as the profound strategic role that virtualization will play in next-generation computing processes from the desktop to the datacenter."

Microsoft wasn't just paying lip service to the importance of virtualization, King maintains. "One company executive spoke at length about the ability of virtualization to 'abstract' -- or disconnect -- applications and processes from both physical hardware resources and specific OS instances. From a user's perspective, applications become simply available and reliably usable."

It's in this respect, however, that the virtualization wave threatens to overwhelm Microsoft, some industry watchers content. After all, notes Gordon Haff, a senior IT advisor with consultancy Illuminata, two of the principal functions of the operating system -- namely, the abstraction from and communication with underlying hardware resources -- are replicated in the virtual arena, typically by a hypervisor.

"Because the hypervisor is the code that is actually sitting directly on top of the server and controlling it, the hypervisor implements a lot of the low-level hardware resource management that the OS historically had to handle on its own," Haff explains. "A hypervisor also adds capabilities that most operating systems didn't traditionally have -- specifically, e ability to itself host a number of isolated OS instances and their associated applications."

The upshot, Haff argues, is that hypervisors go operating systems one better on the abstraction front. "[A] hypervisor also presents a more abstracted view of hardware to the higher layers. For example, 'virtual CPUs' and 'virtual NICs' don't need to correspond to the quantity of physical hardware actually present. They also strive to be as generic as possible -- although, in practice, the desire to completely abstract the underlying hardware has to be balanced against the desire to take advantage of existing driver software, vendor-specific hardware acceleration, and other features."

This doesn't mean that the operating system itself will go the way of the Dodo, just that the role (and scope) of the operating system will likely change, according to Haff.

"One significant implication of all this is that the operating systems that sit on top of a hypervisor don't necessarily have to be OSs in the traditional vein, because the hypervisor is already handling many of the tasks associated with scheduling and other functions associated with the physical hardware," he explains. "Rather, the OS running atop a hypervisor can major in just providing system services for applications."

To a degree, Haff argues, this is already happening. "Linux on the mainframe, running under z/VM, uses precisely this approach. Linux scalability has improved greatly over the past decade, but still can't hold a candle to the biggest of the Big Iron operating systems, but under z/VM, it doesn't have to. The z/VM foundation -- and a lot of support by and for System z hardware -- does almost all the heavy lifting."

The salient point, Haff argues, is that the operating system as we know it is almost certainly going to go away.

"[O]ne can even imagine specialized OSs that provide a well-defined subset of services for specific applications, the idea being that a stripped-down OS tailored to a specific purpose could have a smaller footprint and be more efficient than the historical general-purpose OS that had to be prepared to do anything," he says. "This sort of architecture isn't wholly theoretical even today. BEA's LiquidVM -- a virtualization-enabled version of BEA's JRockit JVM -- can run directly on top of VMware's ESX Server without a conventional OS present. BEA claims performance boosts of up to 40 percent relative to running a JVM on top of a standard operating system."

That's assuming Microsoft can't commandeer the virtualization juggernaut -- much as it did that of the Web browser -- and recast it to serve its own ends.

Should it succeed, industry watchers say, Redmond could even pull off a veritable coup. "If [Microsoft's] strategy ever fully succeeds, the effects on the larger market would be remarkable, tilting balances in the IT market and helping to propel Microsoft to the kind of overwhelming enterprise and data-center leadership to which it has long aspired," he says. "That conclusion may be far in the future, but it is one that, through efforts like the Virtualization Deployment Summit and Dynamic IT, Microsoft hopes to write some day."

In spite of VMWare's commanding market share -- which some industry watchers peg at about 80 percent of the x86 virtualization segment -- King thinks Microsoft's traditional pull with enterprise IT buyers will help give its virtualization push some much-needed traction.

Nor is Microsoft simply banking on brand recognition, either: its expanded partnership with Citrix -- which a decade ago developed the technology on which Microsoft's Windows Terminal Services is based -- gives it access to that company's XenSource hypervisor. Furthermore, Citrix is working on software that can transfer VMs between XenSource XenServer and Microsoft's Hyper-V hypervisor.

King admonishes: don't count Microsoft out.

"Does Microsoft have the intellectual and financial resources necessary to succeed? Absolutely, but fundamental transformations of this sort require time, sustained effort, and visionary leaders empowered to institute change," he says.

"For the time being, we doubt VMware will be significantly affected by Microsoft's efforts, but if the company gains a toehold among the enterprise clients at whom many of its new offerings are aimed, it could shift the dynamics of the x86 virtualization market."