Red Hat has announced a deal with Microsoft that will help boost virtualization compatibility between Windows and Red Hat Enterprise Linux. Both sides are touting the agreement as an important step for empowering interoperability in mixed environments where both platforms are used.

Unlike the controversial agreement between Microsoft and Novell, this deal does not contain any patent provisions or exclusionary intellectual property indemnification arrangements. This represents a major change in direction for Microsoft, because the Redmond giant has consistently refused to make interoperability agreements under such terms in the past.

Shortly after Microsoft and Novell announced their partnership in 2007, Microsoft publicly declared that Linux technologies infringe on hundreds of Microsoft's patents—a claim that has never been substantiated. Microsoft said that it would not negotiate any interoperability pacts with Linux vendors unless they agreed to also sign Novell-style patent indemnification agreements that are hostile to the kind of downstream redistribution that is inherent in the open source development model.

Red Hat offered several times to collaborate with Microsoft on interoperability issues outside the scope of patent agreements, but Microsoft argued that interoperability can't be addressed without first "solving the licensing issue." Microsoft has apparently reversed its position on that matter.

Under the terms of the new agreement, the two companies will mutually participate in each other's virtualization certification programs and collaboratively provide customers with official support for mixed deployments. What compelled Microsoft to do this without an IP indemnification deal? The company claims that it is in response to customer demand.

"Customer demand is the main driver behind these agreements with our competitor," said Microsoft virtualization manager Mike Neil in a blog entry. "Microsoft is pragmatically focused on helping customers and partners be successful in a heterogeneous IT world. We're committed to enable and support interoperability with non-Windows OSes. As a result we take a multifaceted approach to interoperability."

There is a growing body of evidence which demonstrates that Microsoft's approach to open source software is changing. For example, Microsoft is now a contributing member of the Apache software foundation and has released several of its own projects—including the Dynamic Language Runtime—under OSI-approved open source licenses. Microsoft's agreement with Red Hat is yet anther sign that Microsoft is accepting the reality of the open source software industry's large and growing relevance.

Red Hat is the top Linux server vendor and Microsoft has been sacrificing business opportunities by refusing to play ball in Red Hat's court. Microsoft has surely realized by now that Red Hat is never going to back down from its position on intellectual property issues, so Microsoft loses nothing by dropping the IP prerequisite. In the end, this is a win for both companies and their customers.