Carrier-Grade Capabilities May Ring Up Big Linux Sales; Now Eyes Telecom Customers; The software near a quality level that puts Unix's top, core customers in its sights.(INTERNET & TECHNOLOGY)

Byline: KEN SPENCER BROWN

If Linux can run your business, why not your phone system?

Companies that sell the open-source software hope more telecom and networking firms start asking that question.

They're launching beefed-up versions of the open-source software to convince users that Linux can do the job of trusty old Unix -- for a lot less money.

"Linux is quickly becoming the preferred platform for carriers in delivering next-generation services," said Peder Ulander, marketing head for MontaVista Software.

The shift could open a huge new market for MontaVista and other Linux vendors such as Wind River, Novell and Red Hat. It could spell more trouble for Sun Microsystems and other Unix sellers, which count on sales of high-end systems to the telecom market.

Ulander and others are betting on two recent developments: a beefed-up version of the core Linux software called the kernel, and an industrywide standard known as carrier-grade Linux.