The new product should help Citrix keep pace with VMware, which announced its own bare-metal hypervisor at the VMworld conference last October. VMware's product is also due in the second half of this year, a spokeswoman said.

Virtualization has been widely adopted on servers but its use on desktops has been limited. Proponents say it can offer big savings for IT departments because it allows them to create and manage desktop images centrally, instead of on each client individually.

But today's products have drawbacks. In one model, used by Citrix XenDesktop and VMware View, desktop images are stored in virtual containers on a server and streamed to end users. That model can create performance issues for end users, since data is constantly shuttled back and forth over a network. It also doesn't allow users to work offline.

Another model, used by VMware ACE, installs the desktop image on a Type 2 hypervisor on the client OS. That provides better performance and the ability to work offline, but critics say security is weaker because it is dependent upon the security of the client OS.

"The Type 2 hypervisor provides no security to stop the host from snooping on what the virtual machine is doing. It can arbitrarily corrupt it and steal data from it," Pratt said.