XenSource founder Ian Pratt and his sidekick Simon Crosby are leaving Citrix, which bought XenSource for a half-a-billion dollars in late '07, to start a new company called Bromium.

The name obviously suggests Chromium but might easily be mocked like Itanium's been and Chromium might be if they don't come up with "the very cool technology that's going to get a lot of heads spinning" that Citrix claims the stealth operation's working on.

The start-up's reportedly focused on virtualization and security, promising an infrastructure product in the second half that's supposed to let the enterprise embrace consumerization and the cloud.

Apparently it's supposed to address the risks to data and applications implicit in the cloud and with insecure mobile devices and potentially address the threats posed by the recent slew of high-profile attacks on business and government systems.

The big-talkin' start-up expects, it said, to deliver "fundamental changes in platform security from client to cloud."

Citrix, which isn't letting on what it is, believes the development will complement its stuff. Bromium, however, will reportedly be agnostic.

It's gotten a $9.2 million A round from Andreessen Horowitz, which aims to be into anything smelling of money these days, Ignition Partners and Lightspeed Venture Partners.

According to Andreessen Horowitz partner Peter Levine, who's on Bromium's board, "Today's computing infrastructure is brittle and insecure, and that ought to horrify us given the recent growth of cybercrime. Bromium turns today's security model on its head and exploits virtualization and the latest hardware features to shift the balance of power in favor of the good guys." The hypervisor as cop?

Bromium has offices in Cambridge in England and Cupertino in California and its board includes McAfee CTO George Kurtz. McAfee, you will recall, is now owned by an increasing security-conscious Intel.

The start-up says it's already collected engineering talent from Microsoft, VMware, Oracle, McAfee and Nvidia, including CEO and co-founder Gaurav Banga, erstwhile CTO and engineering SVP at BIOS maker Phoenix Technologies Ltd, credited with the creation of HyperSpace - a new platform for instant-on and power efficient computing, and FailSafe - a cloud-based anti-theft and device management system for the PC.

Pratt is officially SVP, products, and Crosby, who had been CTO of Citrix' Data Center & Cloud Division and was CTO of XenSource, is CTO again. (All these lateral moves, Simon.)

Pratt, who was technically VP of advanced products in the Virtualization and Management Division at Citrix, will remain chairman of Xen.org, which houses the open source Xen project, and active in the OpenStack cloud project as well as the Open vSwitch project for virtual networking.

By the way, Xen Summit North America is scheduled for August 2-3.

See www.citrix.com/blogs/bromium.