Sun's Executive VP for Software, Rich Green, has resigned, just as Sun says it will lay off 15-18% of its employees. This is an awkward juxtaposition. Sun is reorganizing its software unit; open source software is at the heart of its business strategy; and the leading spokesman for open source is going away.Change comes, whether we like it or not. But there was much to like with Rich Green at the helm of Sun's software effort. I talked to him in May at JavaOne about Sun's approach and more recently, for a story on where open source code is headed in the enterprise. In Monday's edition of Information Week, Green will be found talking about Sun's strategy two days after he left the company.

Green was a buoyant, always positive personality, admirably so, but so much so that I sometimes wondered if Sun was grappling with the risks of its position. In theory, open source is a disruptive force, overturning the bloated and expensive products that have come before it and generating revenue based on a better-valued, fuller customer relationship. That's what open source companies do. But to play the role of disruptor, the open source code has to be leading edge. It has to offer something that the commercial vendors haven't thought of or haven't been able to deliver. Then, having a toehold in software's No Man's Land, the open source company has to expand it until it reaches some commanding high ground from which it can't be dislodged. Linux did it. JBoss did it. MySQL did it. But few pieces of open source code actually do it and achieve commanding market positions.

Can Sun do it? Yes, I'm sure it can, in select cases, such as the Solaris operating system, identity management and the application server. In the GlassFish Enterprise Server version 3 Prelude, it's incorporated the latest Java 6 improvements while implementing a modular, OSGi architecture, catching the wave of demand for light weight computing on the Web.

The question for Green wasn't whether Sun could do it but could it do it on a comprehensive scale, assembling a large stack of open source Java software, and realize the resulting revenue in time.

Could Sun proceed with the lean, deferred-rewards timeframe that establishing an open source product requires? Green himself was well acquainted with that elongated timeframe and the hazard it posed to a publicly traded company, but he was game to try.

His favorite metaphor, whether talking about open source or getting demo results in front of a live audience, was that of the plane accelerating down the runway toward lift-off. Lift-off, we hope, will still occur, but when it does, clearly someone else will be at the controls.