Advantages of optical fiber over copper

Optical fibre carries data as light pulses through a glass or plastic core, instead of electrons in copper wire. Its advantages over copper:

1. Very high bandwidth: terahertz range, so the data rate (Gbps to Tbps) is far higher than copper.
2. Low attenuation: about 0.2-0.5 dB/km, so repeaters are needed only every 50-100 km, whereas copper needs them every 1-2 km.
3. Immunity to electromagnetic interference: no pick-up from motors, power lines or lightning; no crosstalk.
4. Electrical isolation: no ground loops, safe in explosive or high-voltage areas (no sparks).
5. Security: difficult to tap without detection.
6. Light weight and small size: thin, light cable, easier to install in ducts.
7. Non-corrosive material and long life; resistant to many chemicals and weather.
8. Plentiful raw material (silica), cost per bit is lower on long links.