Raman amps are pretty cool but tricky. For one thing, the power required is pretty high. +1W dBm isn't uncommon for certain Raman amps. At those power levels, you need to be careful you dont cause burns to personel when they are working on the equipment.
The power to run the lasers is usually carried on conductors that are part of the cable itself. The voltages are somewhere in the several kilovolt range so laying submarine cable is also kinda like laying a high-volage transmission line across the ocean.
