l switches that are currently interlaced throughout networks. In densely populated urban and suburban regions within the United States and throughout most of the developed countries in Asia, the Middle East, and Europe, consumers and commercial organizations have reasonably priced high-speed Inter- net access. However, many rural areas lack these connections due to the economics The Public Network of sparse populations and long distances between providers and customers. This is because there are fewer customers in these areas over whom providers can spread the costs of upgrading cabling and equipment. Furthermore, long distances result in higher initial costs to install new fiber-optic cabling. These are major roadblocks that in addi- tion to high consumer prices and slow Internet access have also rendered these areas unattractive to private investors. Rural areas are attempting to overcome these hurdles through a combination of government subsidies and municipally backed build-outs. THE PUBLIC NETWORK The structure of public networks can be broken up into three categories: the core sec- tion, Metropolitan Area Networks (MANs) within cities, and last-mile or access net- works. The list that follows provides a brief description of each. Workers in the telecommunications and data-network industry often use different nomenclature for the same equipment or type of network. For example, core networks are also referred to as long-haul and backbone networks and last-mile networks are sometimes referred to as first-mile networks. Long-haul has the same meaning as core networks, and first- mile and last-mile networks are used synonymously with access networks. In addition, the terms "providers," "carriers," and "Internet Service Provid- ers" (ISPs) are also used synonymously. They all provide voice, mobile service, video, or Internet access. Core networks These links span hundreds of miles and carry traffic between distant cities. In the United States, examples of core networks are those connecting Los Angeles to New York