A car with Onstar is connected via cellular phone to a center in Michigan, where advisers use satellites to locate the vehicle, provide directions, and offer other services like remote locking and unlocking of doors. Onstar is far from perfect, however. The patchwork nature of the nation's cellular communications systems means that when a driver moves from one area to another, the Onstar center often cannot quickly establish communications with the vehicle. And the system is sometimes too slow in providing information. The advisers in Michigan must rely on maps and travel advisory services, so they can't offer instant tips on which bridge or tunnel to use in a tricky metropolitan area like New York.
Rival products rely on maps that are loaded into computers inside the car.
But neither can be updated with real-time information. Internet on wheels. The system shows accidents or traffic jams on a map displayed on the computer screen. It can download about 30 kilobits of data per second, about as fast as a good modem in a personal computer but still not very fast. Daimler says it has made a crucial advance, however, thanks to Metricom, the maker of Ricochet communications systems.