Is multi-mode fiber the optimal choice for long distance runs?

Multi-mode fiber is not the optimal choice for long-distance runs primarily due to its modal dispersion characteristics. In multi-mode fiber, light travels through multiple paths or modes, which can cause the signals to spread out over distance. This dispersion leads to limit on the effective distance over which data can be transmitted without significant loss of signal quality.

Typically, single-mode fiber is preferred for long-distance communication because it allows light to travel down a single path, minimizing modal dispersion. This enables longer distances (typically tens of kilometers) to be achieved without degradation of the signal. Hence, for applications requiring extensive network runs, single-mode fiber is the best choice to ensure high bandwidth and minimal signal loss over long distances.