Answer to Question 1
Cable performance can be impaired by attenuation, crosstalk, and distortion. Radiated media are affected by fog, rain, snow, and solar disturbances. Transmission impairment can result in the transmission signal sent not being the transmission signal received.
Answer to Question 2
Fiber-optic cable, unlike twisted-wire pair or coaxial, transmits signals using light rather than electricity. Because light signals are used, fiber-optic cables do not suffer from electromagnetic interferencesa major advantage. Also, fiber-optic cables experience much less resistance to the signals they carry; therefore, signals travel much farther before they need to be boosted or regenerated. Consequently, fiber-optic signals encounter much less attenuation than those transmitted over a copper mediuma second major advantage. In addition, fiber-optic cable provides excellent bandwidth. Speeds of up to 100 Gbps (billion bits per second) are possible a third advantage. And finally, fiber-optic cables are extremely hard to tap intoa fourth advantage. Fiber-optic circuits provide excellent security. Fiber-optic technology, with all its benefits, is also quite expensive.
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