Patent ID: 8428456

Claim:
A passive optical network (PON) protection method, comprising: monitoring, by a switchover control device, optical transmission data from ports of an optical network unit (ONU) or optical network terminal (ONT) via an optical splitting device connected to an optical link of a working optical line terminal (OLT); determining whether the working OLT or the optical link of the working OLT fails according to a monitoring result; if the working OLT or the optical link of the working OLT fails, connecting a protection optical link, wherein the switchover control device is connected to optical splitting devices on optical links of at least two working OLTs and further connected to a protection OLT via the protection optical link; and instructing the protection OLT to assume control over an ONU or ONT under the working OLT; wherein: the switchover control device is specifically connected to the optical splitting device on the optical link of the working OLT through an optical detector, OD, or a transceiver; and monitoring, by the switchover control device, the optical transmission data from the ONU or ONT port by using the optical splitting device connected to the optical link of the working OLT comprises: monitoring, by the OD or transceiver, uplink optical transmission data from the ONU or ONT port by using the optical splitting device connected to the optical link of the working OLT; wherein after instructing the protection OLT to take over the ONU or ONT under the working OLT, the method further comprises: enabling, by the protection OLT, a laser, and setting up a communication connection with the ONU or ONT under the working OLT; determining, by the switchover control device, whether the OD monitors uplink transmission data of the ONU or ONT within a preset time; and if the uplink transmission data of the ONU or ONT is monitored, the protection OLT continuing to take over the ONU or ONT under the working OLT; if the uplink transmission data of the ONU or ONT is not monitored, disabling, by the protection OLT, the laser and giving up a communication connection with the ONU or ONT.