Multiplexing is nothing new. It allows for extremely intricate communications between multiple users. Back in the day it was called trunking but with the rise of digital communications the ability to multiplex via time division, frequency division, code division, wavelength division and using mathematics to encode onto those multiplexing schemes reduced bit symbology for larger bit-words and the increase in electronic sensitivity (i.e. ability to recognize smaller and smaller channels) allows for massive increases in data throughput. Fiber is only the physical transport means (layer 1) and is limited by physical response of the systems supporting layer 1. Electronic systems can only process so fast. This is much slower than the theoretical bit rate available in fiber optic cable. This is why there is so much interest in quantum processing to overcome many of the physical limitations. As channels become narrower and narrower noise becomes a huge problem in distinguishing signaling between the channels. Regenerative repeaters (both electronic and optical) do create some delays but the systems cannot operate without them. There will only be small, incremental increases in throughput from refining processing at the normal communcations layers up to layer four. At this point increasing bandwidth is a matter of increasing the number of fibers in the ground. I remember, again back in the day, thinking we were styling because we had a few OC48s running through our building. When I left the communciations business having twenty OC192s was no big deal. More and more fiber is the current solution. Adding more wavelengths within a fiber only works to a degree. Inherent noise tends to blur the demarcation between the signaling in a fiber even with regenerative repeaters (fiber lasers) in the mix. As such we run back into the problem of electronics being able to distinguish between the signals. There are many factors that determine this but we used to calculate capacity on almost all components using Erlang calcuations which are probabilistic/statistical methods.
The Frothy Chimp
Cynic Extraordinaire
Back off man, I'm a scientist
Good whiskey, fine cigars, long legged women and blues guitar.
That's what I like.
The strong shall stand, the weak shall fall by the wayside.