Sam Ramji gave an excellent short talk at OSCON 2007 on Linux and Windows Interoperability: On the Metal and on the Wire. Sam described the collaborative work being done inside the Microsoft open source labs to better enable virtualization with the Xen world.
Indeed, Xen comes from a GPL licensed project where Microsoft was a sponsor of the original University of Cambridge work. HP and Intel are still sponsors. (Of course you need to use the Wayback machine to begin to see hints of this.) This is all good. But I couldn't help but wonder at two questions during Sam's presentation:
- What is the patent landscape around virtualization?
- What is Microsoft's position with respect to Xen and Xensource if someone were to attempt a patent run against the project?
A quick check of the USPTO patent database can give us a initial inexact feel for the space:
- Patents with VMWare as the assignee (22)
- Patents with Microsoft as the assignee (7117)
- Patents with Microsoft as the assignee and containing "virtualization" (20)
- Patents with Advanced Micro Devices and containing "virtualization" (4)
- Patents with International Business Machines and containing "virtualization" (130) !!!
- Patents with SWSoft as assignee and containing "virtualization" (2)
- Patents with SWSoft as assignee [SWSoft makes Parallels] (6)
- Patents with Intel as assignee and containing "virtualization" (100)
- You get the idea ...
It's a potentially messy space. As virtualization lives so firmly on the hardware/firmware/software boundary, we don't even need to have the debate over the relevance and merits (or lack thereof) of software patents. Somewhere in that collection of patents there are likely to be hardware patents, or firmware patents indistinguishable from hardware, and they may read on the Xen space.
Are we afraid yet? I'm rattling the sword very very loudly. Worried at all? Even an eensy-weensy bit? Hopefully NOT. VMware, Microsoft, Apple and SWsoft at a glance have been shipping products for some time. Intel, AMD, and IBM have been building hardware to be virtualized for some time. And Xen has existed for some number of years squarely in this space, and academia is not naive when it comes to patent filings. As a company, Xensource has been basing its race for the gold ring on the Xen project. Xensource may even be an easy first target to pursue for a patent troll on the way to bigger and better shakedowns (although I certainly wouldn't bet against Intel, HP, VMware, Microsoft, etc. getting involved early.)
Which brings us to the second question.
Here is a perfect (and safe) opportunity for Microsoft to get out ahead of the curve, and demonstrate that they can learn and that they do "get it" and indeed that they can lead with respect to the licensing debate. They can make the patent grant, here and now, to the Xen project. As an intellectually interesting challenge for their legal team, they would be creating a deliberate license directly related to a project licensed under the GPL and stating (within their control) how their patent license does apply downstream, so as to not interfere with their assertion of patent rights in other areas. The point would be to see how promiscuous they could be with their patent rights in a well defined way. Sort of an interesting idea. Indeed, it becomes a historical and game changing idea with respect to their competitors.
To date their competitors keep rolling positional hand grenades out into the field and the Microsoft legal team feels obliged to leap on every one of them. Mention the GPL and the Microsoft legal team runs screaming with their hair ON FIRE (to borrow a phrase from Eben Moglen's great Ubuntu Live keynote.) Develop an enabling and protective patent license around Xen, and they begin to provide a basis for future interesting debate. [Some of the lawyers may even get to make a name for themselves publishing the brief!]
Of course hell could freeze over too. But it's great to dream.