EML Based Real-time 112 Gbit/s (2×56.25 Gbit/s) PAM-4 Signal Transmission in C-band Over 80 km SSMF for Inter DCI Applications

•For inter-DCI applications, a cost effective solution for high capacity transmission over 80 km SSMF is required.•In this paper, the optimal driving conditions of electro absorption modulated integrated lasers are investigated for transmitting real-time PAM-4 optical signal over 80 km SSMF.•The required OSNR and dispersion tolerance as a function of EAM driving conditions are measured and utilized for transmitting 100 Gigabit Ethernet traffic.•This technique can be applied for optimizing multi-level modulation transmission which use optical transmitter with non-linear transfer curve.