Optical fiber advantages and disadvantages

Optical communication sends information as light pulses through optical fibers (core with higher refractive index than cladding, guiding light by total internal reflection).

Advantages

1. Huge bandwidth: supports Gbps to Tbps data rates and many channels.
2. Low attenuation: about 0.2 to 0.5 dB/km, so repeaters are needed only after tens of km.
3. No EMI or crosstalk: light is not affected by electrical noise, lightning or nearby cables.
4. Security: tapping is hard and detectable.
5. Small size and light weight: easy to install and handle compared with copper.
6. Safe: no sparks, no ground loops; safe in explosive areas.
7. Cheap raw material: silica (sand) is abundant.

Disadvantages

1. High initial cost of terminal equipment (transmitters, receivers, connectors).
2. Difficult jointing and splicing: needs special tools and trained persons.
3. Fragile: glass fiber breaks if bent too sharply or pulled; needs protective jacketing.
4. One-way link per fiber: two fibers are usually needed for two-way communication.
5. Cannot carry electrical power to repeaters or devices; a separate supply is needed.
6. Dispersion and attenuation limit the distance and rate in long links; repair is costly.