Patent ID: 8731399

Claim:
A power saving method in a passive optical network, comprising: when a power supply of an optical network unit (ONU) is turned off and the ONU which is still supported by an electric power stored in a power unit receives an upstream burst timeslot allocated by an optical line terminal (OLT), the ONU dividing the upstream burst timeslot into one or more upstream burst timeslots; and when the upstream burst timeslot is still one upstream burst timeslot, the ONU turning on its own laser unit in said one upstream burst timeslot of the ONU, sending one or more emergent physical layer operations, administration and maintenance (PLOAM) messages in said one upstream burst timeslot without sending data frame or idle frame in the residual bandwidth of the upstream burst timeslot, and immediately turning off its own laser unit after sending said one or more emergent PLOAM messages; when the upstream burst timeslot is divided into two or more upstream burst timeslots, the ONU turning on its own laser unit in each upstream burst timeslot of the ONU, sending one or more emergent PLOAM messages in said each upstream burst timeslot without sending data frame or idle frame in the residual bandwidth of the upstream burst timeslot, and immediately turning off its own laser unit after sending said one or more emergent PLOAM messages; thereby decreasing the usage volume of the electric power stored in the power unit for supporting the ONU completing the procedure of transmitting the emergent PLOAM messages.