Communication Technology Update and Fundamentals, 11th Edition

17

Telephony

Ran Wei, Ph.D. & Yang-Hwan Lee, M.A.^*

Since the 20th century, the telecommunications industry has grown rapidly thanks to the emergence of new technology, services, and the expansion of the telecommunications market. New technologies including wireless telephony and VoIP (voice over Internet protocol) have been eroding the market share of traditional wired telephones. However, the telephone still plays an important role in the telecommunications market, with billions of customers enjoying reliable and high-quality voice services. As of 2006, the number of wired telephone subscribers in the world was approximately four billion, averaging 61 subscribers per 100 inhabitants (ITU, 2008a).

Meanwhile, the U.S. telecommunications market ...