Fiber actually has limitations based on the length of the cable. Photons that travel perfectly straight arrive faster than photons that enter the cable at a ste

Fiber actually has limitations based on the length of the cable. Photons that travel perfectly straight arrive faster than photons that enter the cable at a steep angle and bounce off the walls a lot. Because of this, as you increase transmission rate, you start to get interference between signals, and instead of a clear On-Off, you start to get various degrees of brightness until the signal becomes too degraded.