For Columbia University sociologist Duncan Watts, Microsoft's continuing battle with the hacker and the aftermath of 9/11 share a striking similarity: both reveal the peril and the power of networks. Watts is one of the leaders in an emerging field he terms the "new science of networks." Here, large-scale groups of people and micro-scale networks of biological cells form and reform according to many of the same principles. Watts, who is exploring these theories at Columbia's Collective Dynamics Group, recently published a book on the subject titled Six Degrees: the Science of a Connected Age. TR editors caught up with Watts to discuss, among other things, why engineers should start paying close attention to how human networks operate.

Watts: Well, that name is a bit misleading. Theories of networks have been around for a long time, so the science itself really isn't new. What is new is the synthesis of ideas from a variety of disciplines: math, computer science, sociology, biology. Until recently these fields haven't been aware that we're all working on the same kinds of problems. But now, physicists are starting to get ideas from sociologists, and so on. Collaborations are also starting. That's exactly what our group at Columbia is all about.

TR: What are some basic applications of network science?

Watts: There are lots of applications in, say, the life sciences, social sciences, and engineering. One application that already works is Google. Google takes advantage of the fact that the Web is a network and that the links are created by individuals who all know something. Many links pointing to a particular site is a consensus. That's how Google ranks search results-results far better than those based on content analysis. It's about being connected to people who are connected.

TR: So, this is more than academic theory.

Watts: Absolutely. Corporations could benefit a great deal by thinking about their problems not just as technology or engineering problems but as network problems.

Look at Microsoft. I find it ironic that Microsoft is fighting so hard to not have its software packages segregated. What the company doesn't understand is that its biggest enemy is not the government or Netscape, it's the hacker. You see, one of the software industry's fundamental assumptions is that universal homogeneity is good because you can share all sorts of things. And you can-like viruses. The code red virus spread universally within minutes. If it had a payload, that could have caused massive problems.

Now, if you're a corporation and you get a couple of those things because you have a Microsoft platform, you'll be switching to Linux tomorrow. Microsoft has a tremendous business problem to deal with, and I don't think the company realizes that. By simply trying to make their software more robust, they're approaching the problem in the obvious way. Instead, why not break yourself into a few competing companies that don't produce identical code? That way you decrease the homogeneity so that problems in one software package don't leak over into the other. Then businesses can invest in portfolios of different packages. As antithetical as it sounds, it may be the only way to disrupt the "network"-which is why they have all these problems in the first place.