Tech story on traffic lights in San Francisco. WS of Geary St. CU of traffic light and Van Ness Ave. street sign. Interview with Mike Schubush(sp?) of Cabletron who wants to change how traffic lights work. Computer diagram about smart traffic lights syncing to signal light problems in the City. Richard Hart in front of traffic sign on Van Ness street. Computer diagrams of "Spectrum" system used to control lights. Explanation of how system works when one traffic light breaks. MS shot of two men in front of large desktop computer on expo floor.