VMware attacks Microsoft virtualization strategy

Microsoft is "trying to restrict customers' flexibility and freedom to choose virtualization software by limiting who can run their software and how they can run it."

Those are the charges levied by Microsoft virtualization competitor VMware, which over the past few days, has come out swinging against Microsoft.

On the heels of a New York Times profile of the company and its many complaints against Microsoft, VMware posted a white paper to its Web site that detail its gripes, which range from licensing terms, to closed programming interfaces and formats. (The white paper is dated February 23, but seems to have been made public some time after The Times story was published.)

"Microsoft is leveraging its ownership of the market leading operating system and numerous applications that are market leaders in their respective categories (Exchange, SQL Server, Active Directory) to drive customers to use Microsoft virtualization products. Their tactics are focused on software licensing and distribution terms (for SQL Server, Exchange, Windows Server, Vista) and through the APIs and formats for virtualized Windows," the white paper continued.

Among VMware's specific charges:

• "Microsoft has posted language that restricts use of their VHD-formatted VMs (“VHDs”) to MS Virtual Server and/or Virtual PC only (as opposed to VMware products, which also run VHDs)."

• "Microsoft is strictly enforcing their VHD format on users and ISVs as a closed ecosystem and not allowing compatibility or translation with other formats."

• "Recent changes in Microsoft licensing have taken a negative stance on mobility and virtualization. These new Microsoft licensing policies ask for permanent assignment of operating system licenses to hardware and then restrict the movement of those operating system licenses, even for virtualized environments that can be moved seamlessly from machine to machine."

• "Microsoft has recently announced a prohibition on virtualizing the less expensive versions of Vista (Vista Home Basic and Vista Home Premium)." Microsoft also is limiting the number of times virtualized environments can be moved to different machines, and what kinds of content (anything "protected by Microsoft digital, information, or enterprise rights management technology" can be virtualized.

• "Microsoft has developed proprietary APIs (including but not limited to what Microsoft calls “Enlightenments”) for Longhorn that manage communication between Windows and Microsoft’s hypervisor. Microsoft disclosed these API specifications at the WinHEC conference in June 2006, but is not permitting use of these APIs by other virtualization vendors or open source projects. The one exception is Novell, which agreed to give Microsoft critical operating system intellectual property rights and ongoing payments to Microsoft in return."

In early February, Microsoft officials reiterated the company's decision to allow only certain versions of Vista (Business, Enterprise and Ultimate) to be virtualized, whether the user employed a Microsoft or third-party-developed virtualization product. Microsoft's reason for prohibiting the virtualization of Vista Home Basic and Home Premium: "Virtualization is a fairly new technology, and one that we think is not yet mature enough from a security perspective for broad consumer adoption."

On February 25, Microsoft Virtualization Strategy General Manager Mike Neil posted to the Windows Server team blog an overview of Microsoft's current thinking around virtualization. (His post seemingly was prompted by The New York Times' story on VMware.)

Neil explained Microsoft's multi-pronged virtualization strategy and addressed a number of the criticisms in VMware's white paper in his post. In terms of licensing, Microsoft is allowing Business, Enterprise and Ultimate users up to four installs of Windows in virtualization managers, he said. Neil added security as another reason for Microsoft's decision to limit the virtualization permissions in Vista.

He posted:

"In Windows Vista Enterprise edition we allow the user to have 4 installs of Windows in VMs and they can install and use Vista Business Edition in a VM. Virtualization is a new technology for consumers, and one that isn’t mature enough yet from a security perspective for broad consumer adoption. But for the enthusiasts and early adopters we do provide Vista Ultimate to be used in a VM. As an example we have researched these issues with current virtualization hardware architectures. One area that is clear is that our security and data protection features can potentially be subverted by a malicious virtualization layer. We’re working with the hardware and software industry to improve the security of virtualization technologies and we will evolve our licensing policies as virtualization becomes more widely used on client systems."

On the issue of closed vs. open application programming interfaces (APIs) and interoperability in the virtualization space, Neil said:

"The APIs for Virtual Server 2005 have been available publicly since day 1 on MSDN. And much of the preliminary details on Windows Server virtualization (part of Longhorn) APIs were shared at WinHEC last year, in the included documentation shared with each attendee. And like other Windows APIs, we plan to publish these publicly at beta. We’re doing this because in the end customers with mixed environments expect it all to work together."

Microsoft officials did not respond to a request for more direct feedback to the specific charges in the VMware white paper by the time this blog entry was published. Update: On February 27, I received via e-mail from Microsoft an official response to the VMware white paper. It's at the bottom of this post.)

My biggest question, after reading The Times story and the VMware white paper is when will VMware file a lawsuit? It sounds like VMware -- in spite of its 80 percent virtualization market share -- is gearing up to lodge one heck of an antitrust complaint against Microsoft. (I wonder if VMWare parent EMC Corp. is really up for that kind of move. Maybe.)

What do you think? Is VMware going to sue? Are we heading toward another Microsoft-Netscape contest, but this time in the virtualization space?

Addendum: On February 27, Microsoft supplied an official response to the VMware white paper, attributable to Neil. Here it is in full:

“Microsoft believes the claims made in VMware’s whitepaper contain several inaccuracies and misunderstandings of our current license and use policies, our support policy and our commitment to technology collaboration.  We believe that we are being progressive and fair with our existing licensing and use policies and creating a level playing field for partners and customers.  We are deeply committed to providing high-quality technical support to our customers who are utilizing virtualization technology.  In addition, we are committed to working collaboratively with industry leaders to foster an environment of interoperability and cooperation that best serves our customers.

“We believe it's better to resolve VMware’s claims between our two companies so that we can better serve customers and the industry. EMC is a long-time partner of Microsoft. We've extended this courtesy to VMware due to our mutual customers and partnership with EMC. We are committed to continuing to collaborate with VMware as we have been doing on regular basis. Consistent with this, Microsoft believes that we will be able to accommodate a mutually agreeable solution between our two companies and clear up any existing misunderstanding with regard to the points raised in the whitepaper.”