QoS-aware cyclic sleep control with proportional-derivative controllers for energy-efficient PON systems

This paper proposes a cyclic sleep control scheme on the basis of the queue length (QL) information for energy-efficient passive optical network (PON) systems to cope with diversified quality-of-service (QoS) requirements. Cyclic sleep control is an effective power-saving technique for optical network units (ONUs) in PON systems. In conventional controllers based on the frame inter-arrival time (FIAT) information, however, downstream queuing delay at an optical line terminal is greatly affected by the amount of downstream traffic. Our proposed QL-based controllers with feedback control techniques, i.e., QL-based proportional and proportional-derivative controllers, effectively reduce the power consumption of ONUs while maintaining the downstream queuing delay at a constant level. The simulation results confirm that the proposed controllers provide better performance than the conventional FIAT-based controller in terms of power consumption and average queuing delay.