assessed in trend as a potential solution to improve transmission equipment power efficiency EON's benefit is based on the current trend towards coherent 40 Gbps and 100 Gbps solutions and even higher speed implementations. Instead of having transparent connections underutilized (either because of their overcapacity with respect to actual traffic demands or due to the wide capacity gap between the transponder types). EON exploits the so called Bit-rate Variable Transponder(BVTs), which have different working modes.