hundreds of kilobits per second effective bandwidth or better), but they span a wide range of speeds, with consequences for the types of applications they are able to support. A service may, for example, be fast enough to support rapid Web browsing or a few channels of telephony, but too slow to support even a single TV-quality video stream.

Various groups have struggled to develop appropriate definitions of broadband, and these definitions have changed over time. In the 1980s and early 1990s, broadband referred to rates greater than 45 megabits per second (Mbps), and “wideband” referred to rates between 1.5 and 45 Mbps. Then, circa 1995, broadband commonly referred to anything 1.5 Mbps and higher in most circles; thus, it was an order of magnitude greater in capacity than ISDN service.2 Mandated to report to Congress on deployment, the FCC, in its 2000 report on broadband deployment,3 defined an “advanced telecommunications service” as one that is at least 200 kbps in each direction. The speed and two-way requirement attempted to capture the intent expressed in the Telecommunications Act of 1996—that the speeds of what the act terms “advanced telecommunications services” should exceed the rates offered by the technologies available to residential customers at the time of the act’s passage.4 At the time of the act’s passage, residential customers were generally limited to dial-up service (then typically no more than 33.6 kbps). Hinting that a definition should also be, at least in part, driven by the requirements of user applications, the FCC report also observed that the 200-kbps threshold it selected is roughly the threshold above which the time it takes to load a Web page becomes comparable to the time it takes to turn the page of a book. But a 200-kbps service would be inadequate to support even a single TV-quality video stream to each house, let alone the multiple such streams that a family might reasonably use, which would require multiple megabits per second. Nor do TV-quality video streams represent the most bandwidth-demanding application one could imagine in the future.

These definitional questions also arise in an international context as other countries explore policy options concerning broadband. For ex-

2  

For a historical view of prospective services, see IEEE Network special issue on the North Carolina Information Highway, November/December 8(6), 1994.

3  

Federal Communications Commission. 2000. Inquiry Concerning the Deployment of Advanced Telecommunications Capability to All Americans in a Reasonable and Timely Fashion, and Possible Steps to Accelerate Such Deployment Pursuant to Section 706 of the Telecommunications Act of 1996 (Second 706 report). CC Docket No. 98-146, Second Report, FCC 0-290 (rel. August 21). Available online at <http://www.fcc.gov/Bureaus/Common_Carrier/Orders/2000/fcc00290.pdf>.

4  

The FCC report defines a broader class of services—“high-speed services,” defined as services that exceed 200 kbps in at least one direction—of which advanced telecommunications services are a subset.



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