Adaptive control and performance evaluation of burst transmission in energy efficient GPON

Recently standards organizations have started to make efforts on reducing power consumption in communication networks. For example, IEEE 802.3az is designed to reduce power consumption in Ethernet networks. ITU-T has also proposed a draft of power management for GPON networks. In this paper, we first express that GPON power saving is strongly dependant on network traffic patterns. Even if two systems with the same mean traffic load, different traffic distribution would result in different power consumption. Therefore, we propose a new power management scheme for energy efficient GPON and define a state diagram for the system. Unlike using fixed periods in the ITU-T draft, the state sojourn time in our system is dynamically adjusted. By analyzing the proposed approach, we show that our system can determine the best state to stay so as to minimize power consumption. The second contribution of this work comes from the proposed burst transmission scheme while an ONU is in the power saving state. A light loaded ONU can maximize its sleeping time until either the buffer is full or the maximum packet waiting time reaches a pre-determined value. We have carried out extensive simulations to evaluate the performance of the proposed green GPON approach. Simulation results reveal that the proposed scheme significantly outperforms IEEE 802.3az based control scheme on reducing power consumption for GPON networks.