Energy Efficient Ethernet Passive Optical Networks (EPONs) in Access Networks

As concerns about energy consumption grow, the power consumption of the EPON becomes a matter of increasing importance in the heterogeneous networks. In respect of energy efficiency, the current standard has no management protocols aiming to reduce power consumption in EPONs. To increase energy efficiency while satisfying diverse QoS requirements, the sleep mode operation is introduced in an Optical Network Unit (ONU) and a suitable sleep/wakeup time schedule is determined at the Optical Line Terminal (OLT). The scheduling algorithms are tightly coupled with the upstream bandwidth allocation and downstream transmission profile. Simulation results show that a well designed scheduling discipline is essential to achieving significant energy saving while meeting the delay constraint.