re importantly, the number of users was increasing rapidly. Internet service providers were popping up everywhere; although counts were not defini- tive, Boardwatch Magazine was estimating the number of ISPs in the United States and Canada, in August 1997, as 4,133 [14], up from only around 90 in 1993 [15]. The number rose much more slowly over the next couple of years, stabilizing as some small providers consolidated. The older on-line service pro- viders either faded away or became ISPs. Some of the largest bulletin board operators also became ISPs; the "BBS" business itself rapidly faded. Data Traffic Finally Tops Voice It is hard to tell exactly when the telecommunications industry carried more data than voice traffic, but it probably occurred during the 1995-1997 explo- sion in Internet traffic. To be sure, it is hard to precisely quantify the actual amount of data carried across the Internet. The TCP/IP protocol suite is rather inefficient, SO many links are run at a fairly low percentage of utilization. Band- width is often purchased by ISPs in bulk, ahead of demand, in part because tele- communications providers make bulk bandwidth available in rather coarse multiples (most often 1.544 Mbps, 44.7 Mbps, 155 Mbps, 622 Mbps, and 2,488 Mbps). So bandwidth provided in bulk to an ISP is not necessarily being fully utilized. But it creates demand for the telecommunications providers. And it was the data providers that were sucking up the available bandwidth, not voice-oriented long distance networks. The Internet Boom and the Limits to Growth By 1996, the fiber-optic and SONET networks, installed during the pre- ceding decade by AT&T, Sprint, MCI, and WorldCom's various predecessors, suddenly found themselves running low on capacity. The long-term growth rate for voice traffic had been a few percent a year, giving plenty of time for plan- ning. Competition in the long distance business had led to lower prices and increasing demand but at manageable rates. Interstate long distance calling rose 158% between 1985 a