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Chapter 2Overview of current CATV network p2.2 Evolution of CATV networks and cable modemtechnologyCommunity Antenna Television (CATV) began in 1948 in Astoria, Oregon. It wascreated as a way to improve television reception for people who lived in remote or hillyareas, where good television signal reception was difficult. Since that time, cabletelevision has become a common source of video entertainment for more than 500million viewers around the world [125]. Early interest in cable modem technologyemerged in the 1980s and was focused around the IEEE 802.4 token bus over CATVnetworks.At the same time, research institutions and universities began using the CATVinfrastructure for two-way campus data networking. These institutional networks werecalled I-Nets and were mainly used to connect institutional Local Area Networks(LAN). Unfortunately, such cable modem products were relatively costly tomanufacture and maintain and the resulting broadband data networks were expensive tooperate [63]. Technical obstacles combined with a lack of financial incentive restricteddevelopment. In essence, large-scale investment was required to serve sufficientcustomers for good return.The first organisation to partly overcome these technical difficulties was LANcityCorporation of Andover, Mass. USA in 1990, which became a commercial success withthe development of cable modem technology. LANcity’s cable modems became anessential device as it allowed the CATV networks to extend communications services toentire cities. Soon after LANcity developed its cable modem, Zenith introduced asimilar type of cable modem. By 1992, both of these companies were offering“Symmetrical LAN over cable” [63]. Since then, diverse groups have worked togetherto help cable modem technology and cable data networks standards. Section 2.5presents a number of the CATV standards that support this technology.2-2