In a white paper published on its website, VMWare said that Microsoft's changes the terms of its licenses restricted 'customers' flexibility and freedom to choose virtualisation software by limiting who can run their software and how they can run it.'
The authors of the paper said that Microsoft is using its ownership of Windows, alongside Exchange, SQL Server and Active Directory, to drive customers to use Microsoft virtualisation products.
'In particular, Microsoft does not have key virtual infrastructure capabilities (like VMotion), and they are making those either illegal or expensive for customers,' the authors claimed. 'Microsoft doesn't have virtual desktop offerings, so they are denying it to customers; and Microsoft is moving to control this new layer that sits on the hardware by forcing their specifications and APIs on the industry.'
The company argued that Microsoft has restrictive terms on the use of published virtual machines. '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),' it said.
It said that Microsoft needed to accommodate market choice and interoperability.
'Customers require freedom of choice to implement both Microsoft and non-Microsoft applications running on Windows with any chosen system virtualisation layer,' the author's of the white paper said. 'Customers do not benefit from being forced into a homogenous virtualisation/OS/application stack.'
