Receiver ON time optimization for Watchful sleep mode to enhance Energy Savings of 10-Gigabit Passive Optical Network

Abstract

The Passive optical network (PON) has opened new avenues for the provisioning of very high bandwidths per user through a pure optical fiber based Access Network. However, increasing split ratios in PON are leading to higher power consumption of the PON due to 60% of the power being consumed by the optical network units (ONUs). Recently, watchful sleep mode (WSM) has been added to the PON standards that combines both the cyclic doze and sleep techniques in a single operation by periodically turning on the ONU receiver (RX) during the sleep cycle. However, still, the impact of RX on time on the energy-saving performance of WSM has not been studied.  Therefore, this study presents a performance evaluation of the WSM in a 10 Gb/s PON (XG-PON) network with varying RX (ON) times. The investigation is performed with a dynamic bandwidth assignment scheme and real traffic data from Broadcom CATV headend. A comprehensive review of the power saving techniques for XGPON is also presented. The results of the simulation study show that the maximum energy savings are achieved if the RX ON and  OFF times are set to 100% duty cycle of the Watch state with non-significantly increases in upstream and downstream delays and variance.