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September 20, 2007

Virtual machine specifications, the new BIOS

Way back when IBM first launched the PC, PCs had a BIOS which was necessary to run operating systems on the box. Clean room copying the BIOS allowed the clone PC business to take off. I saw deals with Xen and VMWare to ship the hypervisor with the server hardware from vendors last week. This is interesting because this may be the beginning of a new BIOS. This new BIOS may well be the virtual hardware architecture of these virtual machines. The virtual machines define a spec for a virtual computer. There are virtual network chips, video cards, disk controllers. This combination of virtual hardware is important because when an operating system is installed, it configures itself and installs drivers for that specific collection of emulated hardware.

This is a really important point for customers using these hypervisors as it allows them to create virtual images that can be moved from one server to another and be sure that the image works on the new server. This is the case because the virtual machine doesn't depend on the hardware definition of the physical server it's running on because it uses virtualized hardware not the actual hardware on the server hosting the virtual image. This is great for vendors as it clearly couples the virtual machine image to the hypervisor that created it as it will only run on a hypervisor that emulates that exact virtual server.

There are programs to convert a Microsoft Virtual PC to a VMWare image by switching the device drivers in the image from the ones defined by vendor A to those defined by vendor B but this doesn't always work, especially with virtual machines running Windows as the hardware change is detected and then it requires another activation key from Microsoft.

So, I'm wondering if these vendors are protecting the definition of their virtual machines. If they were protected then effectively they are locking in customers creating virtual images or vendors creating virtual appliances to their hypervisor. VMWares early lead and the fact that XEN and other competitors are using different virtual hardware specifications means that VMWare has a lot of appliances etc available on its hypervisor and they won't run easily on competitive hypervisors, especially if they are windows based.

So, are we seeing virtual machine vendors using their virtual machine specifications as a form of IP that is legally protected? I don't know the answer to that but it's easy to see why a forward thinking vendor would try to get protection around a virtual machine specification. If any vendor can use VMWares virtual machine specification then customer will be able to move away from VMWare. If not then switching hypervisor vendors won't be easy and a significant amount of work. This then means that once a customer starts to use a particular hypervisor then they may well be locked in to that hypervisor.

We need an open source virtual machine specification as an industry standard.

What customers need but vendor may not pursue without a lot of pressure is an open source or industry standard virtual machine definition thats implemented by all vendors. That would of course prevent lockin and so is unlikely to be vigorously pursued by the dominant vendors but it would clearly benefit customers and allow competition to keep prices reasonable as the technology matures due to the ability of customers to switch vendors based on price or other factors without incurring a huge migration cost.

So, who will be the first to clone the new BIOS and create the new clone business or is the new BIOS/virtual machine specification protected? Thats the question today.

Download devwebsphere_2007_09_20.m4a

September 20, 2007 | Permalink


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