Patent ID: 8886041

Claim:
An optical line terminal to be coupled to a plurality of optical network units via optical communication, comprising: at least one processor; and at least one non-transient storage medium connected to the processor which stores information of time points at which the optical network units respectively start to enter a first transient period from a powered-on state to a powered-off state or a second transient period from the powered-off state to the powered-on state during which said optical network unit can emit an unintended light signal, and the at least one non-transient storage medium storing instructions which cause the processor to execute: a determination part configured to determine a first time point at which a first optical network unit of the optical network units starts to enter one of the first transient period or the second transient period; a transmission part configured to transmit a state control signal containing the first time point to the first optical network unit in order to control the first optical network unit to start to enter the one of the first transient period or the second transient period; and an allocation part configured to stop allocating a bandwidth, used to transmit a signal to the optical line terminal, to a second optical network unit of the optical network units other than the first optical network unit during the one of the first transient period or the second transient period during which the first optical network unit can emit the unintended light signal.