The last time Reston-based Noblestar spun off a company, it was sold to Aether Systems Inc. for $900 million after just 13 months as an independent firm.

A repeat of the success encountered by that spinoff, Riverbed Technologies Inc., might be a lot to ask, but Jill Stelfox is taking her chances. In early 2002 Stelfox led another Noblestar unit on its own, and she now serves as the chief executive of Defywire Inc.

Unlike engineering services firm Noblestar, Defywire sells a software product that connects cellular phones and handheld computers with business networks. The premise is not a novel one, but Stelfox claims the technology is.

The main questions the company sought to answer, she said, were "How do you get data to mobile workers so that it's fast, efficient and secure? How do you get the ability to place a customer order, or get your new schedule or order parts remotely, without logging on to a laptop?"

Defywire's answer was to build a Java-based application that presents users with familiar icons that connect them with company data within two seconds. The firm, also headquartered in Reston, is targeting companies with large forces of sales or service workers and transportation firms. Installation of the system usually takes fewer than 10 days, Stelfox said, and because the screen looks like that of a laptop, no training is needed.

The software took nearly 10 months to develop, but went on sale in October. Defywire has partnerships with a number of big companies, including Sun Microsystems Inc. and Sharp, and so far has generated about $500,000 in revenue, Stelfox said.

"After Riverbed, we spent a long time looking for the next big thing," and now, she said, she believes they've found it.

Defywire chief executive Jill Stelfox and Chief Technology Officer Chuck Gautney hope to repeat the success of a previous Noblestar spinoff.