Cooperative cyclic sleep and doze mode selection for NG-PONs

This paper presents an energy efficient medium access control (MAC) protocol exhibiting intelligent switching among optical network unit (ONU) transceiver power levels. This is implemented by introducing a new methodology at the ONU ActiveFree state of next generation passive optical networks (NG-PONs) based on the adaptation of standard local sleep and local doze queue indicators (LSI and LDI) to a more comprehensive grated mode selection policy. In particular the mode selection is not only based on Q_low and Q_high traffic conditions, representing the absence or presence of traffic. Dense mode selection thresholds are applied instead that grate queue traffic providing fine switching between cyclic sleep and doze. Performance evaluation figures such as transceiver power consumption percentage, delay, and queue size were drawn under different network loads and varying sleep intervals. Computer simulations have shown transceiver power consumption levels of 44%, following the application of only cyclic sleep, a power consumption of 63% with only doze mode and a reduced consumption down to 25% in the presence of the proposed grated mode selection policy.