Terrestrial optical fiber communication with added capacity

An optical communication system comprising:

• an optical fiber connected to a first signal regeneration node located at a first end of the optical fiber and a second signal regeneration node located at a second end of the optical fiber;
• intermediary nodes located between the first and second signal regeneration nodes, wherein one or more pairs of adjacent intermediary nodes each define a span distance along the optical fiber;
• and
• one or more Raman amplifiers located within each span distance along the optical fiber, wherein at least one of the one or more Raman amplifiers comprises:
• a case that encases:
• one or more lasers;
• and
• a temperature controller comprising:
• a temperature sensor to monitor a temperature of the one or more lasers;
• and
• a temperature regulator to control a temperature of the one or more lasers.

A method, comprising:

• measuring a first signal power of an optical signal at a node upstream and adjacent to a Raman amplifier;
• measuring a second signal power of the optical signal at another node downstream and adjacent to the Raman amplifier;
• calculating a difference signal power value based on a comparison between the first signal power to the second signal power;
• determining whether the Raman amplifier is working based on the difference signal power value;
• and
• generating an alert if it is determined that the Raman amplifier is not working