is used by telecommunications companies to transmit telephone signals, Internet communication and cable television signals. It is also used in other industries, including medical, defense, government, industrial and commercial. In addition to serving the purposes of telecommunications, it is used as light guides, for imaging tools, lasers, hydrophones for seismic waves, SONAR, and as sensors to measure pressure and temperature.
[pdf] Passive optical networks were first proposed by in 1987. Two major standard groups, the (IEEE) and the of the (ITU-T), develop standards along with a number of other industry organizations. The (SCTE) also specified f.
[pdf] Telecommunications in consists mainly of , analog,,,, and , and the. Telephone service is provided through (Telecommunications Company of Cuba), mobile telephone service is provided through the Cellular Telephone Company of Cuba (CUBACEL) and, previously, Caribbean Cellular (Celulares del Caribe, C-COM - no longer operating). Cuba's main international telecommunications links are through,.
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