Virtualisation is not just about consolidating servers, but has far reaching implications across corporate cultures.

"Virtualisation raises questions of politics, such as who owns the servers, who pays for them and who manages them," said Richard Curran, director of Intel's digital enterprise group. 

"They have to start thinking of the data centre as a shared capability, a service, not a room housing 'my box'."

Curran pointed out that culture changes more slowly than technology and that it will be some time before users accept that they cannot point to 'their server' in the data centre.

Virtualisation provides users with shared access to applications and computing resources, regardless of the physical location of the resources.

Vendors and users have concentrated on consolidation, the ability of virtualisation to shrink the number of hardware boxes in the data centre by deploying a smaller number of more powerful servers to share between the same number of applications and users.

The main advantage has been better use of computing resources. For example, during the daytime traders in a New York financial services company can use their data centre for trading applications. But at night software engineers in India can use the same data centre for development.

Companies are now focusing on business continuity. If a business consolidates six mail servers into one, and that server fails, all mail fails rather than one-sixth of mail.

Consequently, vendors building servers to support virtualisation are concentrating on high-reliability features, and companies deploying virtualised applications are seeking service level agreements not on individual servers, but on entire application services.

However, virtualisation changes the way people think about IT assets because they can no longer point to a server and say 'there is my data'.

It is a cultural change that virtualisation vendors such as VMWare and Zeus are having to overcome.