A group of six server builders and virtualisation vendors plans to reveal a new standard to help IT departments automate the installation and deployment of virtual machines.

The proposed Open Virtual Machine Format (OVF), created by Dell, HP, IBM, Microsoft, VMware and XenSource, provides metadata about virtual machines such as memory, storage and networking requirements.

OVF also lists special feature requests like the need for certain chip instruction sets or large demands for floating point or integer calculations.

The standard allows for integrity checks, ensuring that a machine has not been altered during storage or shipping.

Makers of virtual appliances can use OVF to include licensing information, requiring the user to agree to certain terms and listing the maximum number of allowed installations, for instance.

OVF will not enforce the licences, although such technology could be created at a later stage.

The standard also allows the creation of application stacks where multiple virtual systems are stored in a single OVF file with one set of metadata.

As a file is deployed, the virtual machine monitor could automatically create each of the machines.

The group of vendors has submitted OVF as a draft to the Distributed Management Task Force (DMTF) standards body, and a version 1.0 is expected in six to nine months.

"Being able to encapsulate images to load or distribute virtual machines in a standard way is becoming really important," Winston Bumpus, president of the DMTF and director of standards architecture at Dell, told vnunet.com. "This represents a paradigm shift in how virtual machines are deployed."

IT staff installing a new virtual machine have to manually assign storage, memory and a number of processor cores. OVF offers a standard way to describe such requirements by allowing this step to be automated.

Fully automating the deployment and installation of virtual machines, as well as the image integrity checks, will mostly benefit the market for virtual appliances.

A virtual appliance is a preconfigured application that ships with its own operating system, allowing users to load the image into their virtual machine monitor.

"The appliance business model is in its earliest stages," said Simon Crosby, chief technology officer at XenSource, which offers an implementation of the Xen open source hypervisor.

"It took these added requirements for integrity checks and a licence check [to mature]."

Crosby expects that OVF will initially find the most use in large enterprises, where administrators could use it to create standard packages with working configurations that can be deployed across multiple servers.