The public Internet is currently far smaller, in both capacity and traffic, than the switched voice network. The private line networks are considerably larger in aggregate capacity than the Internet. They are about as large as the voice network in the U.S., but carry less traffic. On the other hand, the growth rate of traffic on the public Internet, while lower than is often cited, is still about 100 % per year, much higher than for traffic on other networks. Hence, if present growth trends continue, data traffic in the U.S. will overtake voice traffic around the year 2002 and will be dominated by the Internet. 1.