What type of fiber optics is typically used for long-distance communication?

Single-mode fiber is typically used for long-distance communication due to its design and characteristics. This type of fiber has a small core diameter (around 8 to 10 micrometers) that allows only one mode of light to propagate through it. This restriction minimizes modal dispersion, which occurs when multiple modes of light travel at different speeds and angles, leading to signal degradation over long distances.

As a result, single-mode fibers can transmit data over much greater distances compared to multi-mode fibers, which have a larger core (about 50 to 62.5 micrometers) and support multiple light modes. While multi-mode fibers may be suitable for shorter distances in LANs and other local applications, they become less efficient over longer distances due to increased signal loss and modal dispersion.

Plastic optical fiber is designed for short-distance applications and is less suitable for long-range communication due to higher attenuation and signal degradation. Step-index fiber refers to a type of fiber where the core has a uniform refractive index; while it can be either single-mode or multi-mode, it’s the single-mode variant that is most effective for long distances.

Thus, the use of single-mode fiber is a crucial factor in achieving high data transmission rates and maintaining signal quality over extensive networks