Here's a typical technology trajectory: at first the new technology is the property of a few visionaries and engineers. They do their best to bring it to market and spread the appetite for it. They succeed. Too well, in fact, and in a few short years, the general public is sold on the revolutionary promise of the new way of doing things. Investors and consumers expect the world to change-and fast. But the payoff can't keep up with the public appetite, and pretty soon public expectation crashes, coming to rest way down below what the payoff might ultimately be. The technology itself, however, just keeps chugging along, and a decade or two later-presto, the revolution does happen. But by then, everybody's forgotten about it. It's just part of life.

That generic fable of boom and bust describes lots of technologies. Think of electricity. Or the automobile. Both roused enormous hopes, disappointed many people, then more quietly transformed just about everything. The same is true of the bandwidth revolution now underway.