Enterprises that want to keep desktops stable and safe can virtualise individual programs, said enterprise IT management vendor LANDesk Software, as it launched new technology that isolates applications from the operating system.

LANDesk Application Virtualization, has been billed as a new way for IT administrators to distribute software to clients. It could be used to run older applications without the overhead of virtualisation software; support multiple versions of mission-critical software, like browsers; and add another layer of security, said Coby Gurr, LANDesk's product manager.

"Enterprises are not moving to Vista yet, but they're looking at what it will take to move to Vista," said Gurr. "And what they're seeing in some cases is a 40 percent failure rate of their current applications. What do they do? Virtualisation? Suddenly I have to patch two operating systems, learn two ways of doing things, support two OSes. That's where we're starting to see application virtualisation, or application isolation, step in."

To take the case with Vista, applications not yet compatible with the OS can be run virtualised on its desktop, giving an enterprise the ability to retain legacy apps without relying on an actual virtual machine, where an older OS - Windows 2000, for instance - consumes memory and requires additional support.

LANDesk's process packages the application code - including everything from drivers to registry keys, then adds a small 400KB runtime to produce an executable file (.exe) that can be run without installation or disturbing the client's operating system.

"We take an application, take its registry keys, and compress it in a single .exe that never installs," said Gurr. "It can be run from a thumb drive, from the desktop, or streamed from a network share." The application packaging takes less than five minutes, and with the small runtime, which Gurr characterized as "like a mini OS," the performance impact compared with a non-virtualised version of the applications, is "minimal."

LANDesk itself uses the new Application Virtualization to run both the older Internet Explorer 6 and the newer Internet Explorer 7 side-by-side on the same system. "We have external systems that just do not work with IE 7," said Dan Cook, LANDesk's director of public relations.

"Running the two on the same machine isn't possible except with application isolation," added Gurr. "With it, I can get used to the new UI [of IE 7] without the two conflicting or fighting with each other."

And the technology can also be used by enterprises to give users choice without the hassle of top-to-bottom support from IT. "If some want to use Firefox as their browser, I can virtualize it and put it on the desktop without installing it," Gurr said. The install-free concept means that the enterprise-mandated desktop environment remains pristine and sacrosanct.

Securing that desktop can also be simplified by isolating applications. The Department of Defense, which is testing Application Virtualization, requires desktops to be completely locked down, said Gurr. "Users aren't allowed to install, they can't write to the registry." But using LANDesk's technology, the DoD can provide workers with virtualized applications that don't disturb the system.

It's even possible to replicate the kind of additional security that Internet Explorer 7 (IE7) offers in Vista, said Gurr. In Microsoft Corp's newest operating system, IE7 runs in what the developer calls "protected mode," which blocks changes to Windows and prevents hackers from easily installing their own malicious code if the browser is exploited. "[Application Virtualization] can isolate the app entirely," Gurr said. "You can go in and modify settings before packaging it, so that any changes [the browser] makes are kept without the isolation layer."

Packaging an application for virtualization is done by taking a snapshot of a machine, installing the application, then taking a second snapshot. The difference is what's bundled into the executable.

The application isolation technology has been integrated with LANDesk's management software, which lets administrators track virtualised programs just as if they were "real" applications. That includes, said Cook, inventorying virtualised applications, tracking license usage, distributing apps to client systems and streaming applications from network shares.

Application Virtualization is priced starting at US$38 per seat, said Cook. "Street is going to be less than that," he said.