IT contractors helping businesses with cloud computing should be aware that virtualised servers are likely to be less secure than traditional physical servers, a leading IT research company has claimed.

According to research by Gartner, only 18 per cent of company data that can be virtualised had been so by the end of 2009, yet this figure is expected to rise to 50 per cent by 2012.

By this point, 60 per cent of virtualised networks will be less secure than the physical servers they replaced, Gartner claimed.

Vice president at the company, Neil MacDonald, said that virtualised networks are not "inherently" insecure.

"However, most virtualised workloads are being deployed insecurely. The latter is a result of the immaturity of tools and processes and the limited training of staff, resellers and consultants," Mr McDonald added.

Adoption of cloud computing systems is growing at a rate six times faster than that of traditional IT, according to market intelligence company IDC.