This is about as big as it gets, there are not many systems bigger than this and even if there are, it's pretty difficult to exceed the 200km distance with any amount of power due to the earths curvature. Wit.
Dense wavelength-division multiplexing (DWDM) refers originally to optical signals multiplexed within the 1550 nm band so as to leverage the capabilities (and cost) of EDFAs, which are effective for wavelengths between approximately 1525–1565 nm (), or 1570–1610 nm (). EDFAs were originally developed to replace optical-electrical-optical (OEO), which they have made pra.