L band. The long span (90km) is compensated by the very low attenuation fiber (0.166 dB/km). The first two systems presented in the table are for long haul application. The first exper- iment is interesting since its scope was not to transmit a huge capacity but to verify what dispersion compensating scheme is optimum for such a system. The result, achieving the performances reported in the table, was that the optimum performance is attained by elec- tronic equalization via nonlinear equalizer without any DCF in line. It is possible that this result depends on the particular system scheme, a low number of channels, recirculating loop, and SO on; in any case it is an interesting suggestion. The third system is a sort of prototype of a potential long haul native 100 Gbit/s system, showing all the potentialities of the employed technologies. The fourth system is a long single span system. It uses the remote Raman pumping tech- nique with an impressive Raman pump injecting 5.5W power into the fiber to create gain of about 140 km far from the end terminal. The fourth system is a demonstration of the possibility to go beyond 100 Gbit/s, with a comb of 175 Gbit/s channel transmitted on more than 400 km of fiber. References 1. Shabtay, G., Mendlovic, D., Itzhar, Y., Optical single channel dispersion compensation devices and their application, Proceedings of European Conference on Optical Communications ECOC 2005, Glasgow, U.K., Vol. 3, pp. 321-323, 2005. 2. Drummond, M. V. et al., Tunable optical dispersion compensator based on power splitting between two dispersive media, IEEE Journal of Lightwave Technology, 28(8), 1164-1175 (2010). Ikuma, Y., Tsuda, H., AWG-based tunable optical dispersion compensator with multiple lens structure, IEEE Journal of Lightwave Technology, 27(22), 5202-5207 (2009). 4. Seno, K. et al., Tunable optical dispersion compensator consisting of simple optics with arrayed waveguide grating and flat mirror, IEEE Photonics Technology Letters, 21(22), 1701-1703 (2009). 5. Seno, K. et al., 50-Wavelengt