How are the new networks different? First, they are integrated, meaning that all media— be they voice, audio, video, or data—are increasingly communicated over a single common network. This integration offers economies of scope and scale in both capital expenditures and operational costs, and also allows different media to be mixed within common applications. As a result, both technology suppliers and service providers are increasingly in the business of providing telecommunications in all media simultaneously rather than specializing in a particular type such as voice, video, or data.
Second, the networks are built in layers, from the physical layer, which is concerned with the mechanical, electrical and optical, and functional and procedural means for managing network connections to the data, network, and transport layers, which are concerned with transferring data, routing data across networks between addresses, and ensuring end-to-end
The telecommunications-related industries are also a major employer—communications services employed 1 million U.S. workers in 2002, representing 1.1 percent of the total private workforce, and communications equipment companies employed nearly 250,000 people.5 Moreover, telecommunications is a high-tech sector, with many highly skilled employees.
Telecommunications is a growth business. Although markedly reduced investment in some parts of the sector (following the bubble years of the late 1990s) may have given an impression of low growth in the long run, a longer-term view taking into account the need for humans and machines to communicate suggests that telecommunications will continue to grow apace, as evidenced by the ongoing expansion of wireless and broadband access services throughout the world.
Telecommunications is also a key enabler of productivity across the U.S. economy and society.6 Not only is telecommunications an industry in itself, but it also benefits nearly every other industry. In the 1990s the U.S. GDP grew rapidly, and the U.S. economy was among the strongest in the world. It is widely believed that the Internet economy played a significant role in this success.
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