Organisational issues within large IT departments are the major factor holding back virtualisation, according to VMware chief executive Diane Greene.

Virtualisation spans areas such as storage, servers and network security, often requiring cooperation between several groups within a company.

"[Organisational silos are] one of the things that holds back virtualisation deployments because the different groups have to agree about procedures and impact," Greene told vnunet.com in an interview at the VMworld 2007 conference in San Francisco.

"You want to start shifting to an organisation where a certain group does the hardware and a certain group does the infrastructure and then a different group does the business applications.

"The people that do the business applications really do not need to be concerned with operating systems or the hardware or anything like that."

Large firms typically have an advantage over small businesses, in that they are often the first to use new technologies because they can afford the required investment and have the necessary staff.

But these roles are reversed with virtualisation. Small businesses typically have only one person managing IT, so they are able to deploy virtualisation and gain the benefits such as increased server consolidation and power savings.

Greene explained that VMware plans to develop additional tools to help firms set up and manage virtual systems, allowing the technology to span these groups with a minimal impact on the organisation.

VMware actually derives more revenue from the sale of tools than from its hypervisor. Such tools assist users in moving virtual workloads to different servers while running through VMware's Vmotion technology.

The ability to perform so-called live migrations is one of the strengths of VMware compared with Microsoft's Viridian technology, which is slated for availability some time next year.

Microsoft was forced to delay the product earlier this year and had to pull several features, including a live migration capability and the ability to add processors and memory to a running machine.

The software giant also scaled back the maximum number of supported processors from 64 to 16.

• A video of the full Diane Greene interview is available on vnunet.com TV