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Analog |
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Digital |
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Both are two-state in data communications: |
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Two frequencies for analog |
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Two voltage levels for digital |
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Each bit is encoded as voltage or frequency
state |
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Group of bits is encapsulated with start and
stop and parity bits |
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Encoded data is merged onto existing signal |
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Principle devices for this are |
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MODEM (modulator/demodulator) |
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Multiplexer (MUX) |
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Twisted pair (STP and UTP) |
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Coax |
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Optical Fiber |
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Microwave |
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Satellite |
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Radio |
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Infrared |
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Cellular Radio |
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Traits: |
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Speed (T-1) |
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Accuracy |
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Privacy |
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Cost (installation and maintenance) |
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EMI resistance |
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Weather resistance |
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Theft resistance |
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You are asked to recommend a wiring system for
your company. What questions would
you have to ask before you could make an informed recommendation? |
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Notes