ONU-driven Energy-saving Method in an EPON by Implementing Look-ahead MPCP-2

We propose a simple and effective optical network unit (ONU)-driven energy-saving method in an Ethernet passive optical network implementing a look-ahead-enhanced multipoint control protocol with a parameter 2 (MPCP-2). In the proposed method, with help of MPCP-2, each ONU has the knowledge of next cycle's transmission before executing current cycle's transmission. Therefore, each ONU enters power-saving mode between two consecutive upstream transmissions with a self-defined sleep time immediately after the completion of the current cycle's transmission. In addition, when the sleep time expires, the ONUs can prolong himself the power-saving mode without waking up in every cycle if specific conditions are satisfied and consequently, no sleep-control message between the ONU and the optical line terminal is required. Thus, energy can be saved at ONUs during the idle time between consecutive cycle transmissions or over several cycles by allowing the ONUs enter power-saving mode under ONU's self-decision. The simulation results demonstrate that the power consumption of ONUs could be reduced by 52.5- 56.0% over the entire traffic load.