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] This guide provides a practical, standards-based approach to selecting managed industrial Ethernet switches and designing robust OT networks. Industrial fiber optic Ethernet switches are designed to deliver stable, long-distance, and interference-resistant network connectivity in harsh industrial environments where copper Ethernet is limited by distance or electromagnetic noise. Unmanaged switches are the simplest active network. To overcome the barriers caused by different protocols, the International Electrotechnical Commission (IEC) developed IEC 61850, which provides a standard communication protocol for electrical substations and power grid automation.
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