On a giant screen at the Corning Museum of Glass in upstate New York, video images flash by-news footage of a war, an inauguration, a spaceshot, a game show-along with real-time projections of museumgoers staring up in wonder. The source of all these images? A strand of glass, thinner than a human hair, yet wide enough to carry more information than three million copper wires, the technology it replaced. Cor-ning is justified in showing off its invention: optical-fiber technology ranks as one of the technological miracles of the 20th century.

Too bad we're in constant need of new miracles to keep up with the voracious network demands that this century is placing on these thin glass fibers. Fiber optics is, after all, a pre-Web technology; and much of the fiber that carries-in addition to telephone conversations-today's e-mail messages, music downloads and video streams was installed before most people were even aware of those media. What used to seem like a shameless waste of capacity now seems woefully inadequate. Our appetite for bandwidth is growing at an exponential rate, with no sign of slowing. Tracey Vanik, technical director at telecommunications consulting firm RHK, compares the Internet to Star Trek's voracious Borg: "Whatever bandwidth is made available, the Internet will swallow."