Red Hat has expanded its support for virtualization technologies with the acquisition of Israeli software company Qumranet, developer of the open-source KVM (kernel-based virtual machine) project, for US$107 million.

KVM is an extension to the Linux kernel that allows it to be used as a "bare-metal" hypervisor, running directly on the underlying hardware and hosting guest operating systems, said Red Hat CTO Brian Stevens.

Hypervisors allow several operating systems to run independently on the same processor at the same time, with the hypervisor managing resources and ensuring that they don't interfere with one another. Depending on the technology used, the operating systems may be different from one another, or different instances of the same operating system.

A closer hold on KVM will be useful for Red Hat, which announced in June that it is building an embedded hypervisor with Web-based management capabilities, Ovirt, based on the software.

"Through this acquisition, Red Hat is assuring that KVM will remain open," Stevens said Thursday, on a conference call with the press.

Red Hat also sees the acquisition as a way to maintain a lead in the market.

"VMware runs on a version of Linux, and Citrix runs on a clone of Red Hat. Both companies need to wait for Red Hat to introduce new features," Stevens said.

Until now, Red Hat has concentrated its virtualization efforts on a rival open-source hypervisor, Xen. That project is hosted by XenSource, a company acquired in 2007 by Citrix Systems.

However, Red Hat will continue to provide support for Xen to users of Red Hat Enterprise Linux 5 at least until 2014, and will continue to contribute to development of the Xen project, Stevens said.

Qumranet also develops Solid ICE, a virtual desktop infrastructure that allows enterprises to host multiple virtual Windows and Linux desktop operating systems on a server running KVM.

All Qumranet employees, including the executive team, will join Red Hat, the companies said.

"We see this as a great opportunity to extend the KVM vision. We couldn't find a better partner for KVM and Solid ICE," Qumranet CEO Benny Schnaider on the same conference call.

The IDG News Service is a Network World affiliate.