AFAIK light can travel for up to 40km in fibre without requiring booster(s).
But in answer to the OP, yes there is light loss in a FTTP circuit at various points. During the testing phase of my FTTP line and also later on when there was a fault*, i saw Openreach go around the various points (ONT/CSP/DP/splitter/agg node) measuring light loss. I believe there is a certain tolerance wrt light loss, though I have no idea what the actual numbers are.
But at the end of the day, if your FTTP service works then you have nothing to worry about.
*the "fault" actually turned out to be a human error as someone had messed up my line profile at the exchange - a line reconfig cured this but only after the Engineer had spent 8 hrs outside in the pouring rain tracing the fibre all the way back to the exchange.
FluidOne FTTPoD 330/30 Mbps
Netgear XR700 running DumaOS
Edited by baby_frogmella (Sat 08-Dec-18 12:02:05)