A method for channel management in an optical network unit includes receiving a disable channel action message sent by an optical line terminal, wherein the disable channel action message is used to instruct disabling a first channel of the optical network unit; transferring the state machine of the optical network unit on the first channel from the association substate of the operation state to the pending substate according to the disable channel action message; and turning off the transmitter and/or the receiver on the first channel after a specified time is reached, transferring the state machine from the pending substate of the operation state to the disabling channel status, and starting a timer.

Methods and apparatus are provided for receiving an optical signal. In one aspect, a method includes receiving a first optical signal comprising time division multiplexed transmissions from a plurality of optical transmitters, and determining that a transmission is not received during a time period from a first optical transmitter of the optical transmitters that is scheduled to transmit during the time period. A second optical signal is inserted into the first optical signal during the time period, the second optical signal having at least a non-zero power portion.

A method of communication includes receiving, by an optical line terminal (OLT), a registration request from an optical network unit (ONU) through a specific upstream wavelength, assigning, by the OLT, out of a plurality of normal service upstream wavelengths and a plurality of normal service downstream wavelengths in a wavelength resource pool, a normal service upstream wavelength and a normal service downstream wavelength to the ONU for a normal service between the ONU and the OLT, and informing, through a specific downstream wavelength, the ONU of information regarding the normal service upstream wavelength and the normal service downstream wavelength. The specific downstream and upstream wavelengths are reserved for a registration process that includes receiving, through the specific upstream wavelength, the registration request and sending, through the specific downstream wavelength, the information regarding the normal service upstream wavelength and the normal service downstream wavelength.

The present invention discloses a high-precision and large-dynamic-range fault monitoring device and method for a WDM-PON. The monitoring device includes a WDM-PON optical network system and an optical network monitoring system. The optical network system includes an OLT I, a feeder fiber II, a 1×n AWG III, a branch fiber IV, and an optical network unit V The optical network monitoring system includes an FP laser, a coupler, an optical coupling device, a photodetector, a signal acquisition and processing device, and an optical feedback device, where the FP laser is connected to the coupler; a large-coupling-ratio output end of the coupler is connected to an input end of the optical coupling device, and a small-coupling-ratio output end of the coupler is connected to an input end of the photodetector; the optical coupling device is installed on the feeder fiber II.

This disclosure describes devices and methods related to multiplexing optical datasignals. A method may be disclosed. The method may comprise receiving, by a dense wave division multiplexer (DWDM), one or more optical data signals. The method may comprise combining, by the DWDM, the one or more optical data signals. The method may comprise outputting, by the DWDM, the combined one or more optical data signals to a first circulator. The method may also comprise combining, by the WDM, the second optical data signal and one or more third signals, and outputting an egress optical data signal to an optical switch. The method may also comprise outputting, by the optical switch, the egress optical data signal on a primary fiber.

An optical access network includes an optical hub having at least one processor. The network further includes a plurality of optical distribution centers connected to the optical hub by a plurality of optical fiber segments, respectively, and a plurality of geographic fiber node serving areas. Each fiber node serving area of the plurality of fiber node serving areas includes at least one optical distribution center of the plurality of optical distribution centers. The network further includes a plurality of endpoints. Each endpoint of the plurality of endpoints is in operable communication with at least one optical distribution center. The network further includes a point-to-point network provisioning system configured to (i) evaluate each potential communication path over the plurality of optical fiber segments between a first endpoint and a second endpoint, and (ii) select an optimum fiber path based on predetermined path selection criteria.

The present invention discloses a passive optical network communications method: reporting, by an optical network unit, ONU, a calibration record of the ONU, where the calibration record includes an ID of a calibrated wavelength channel; sending a first message to the ONU when the OLT determines, according to the calibration record, that a target wavelength channel ID corresponding to a target wavelength channel to which the ONU needs to switch is not in the calibration record, where the first message includes a forced wavelength switching flag; and instructing the ONU to switch to the calibrated target wavelength channel. In this way, the ONU can implement wavelength switching quickly after calibrating a new wavelength channel so as to perform data communication over the calibrated new wavelength channel.

Methods and apparatus are provided for receiving an optical signal. In one aspect, a method includes receiving a first optical signal comprising time division multiplexed transmissions from a plurality of optical transmitters, and determining that a transmission is not received during a time period from a first optical transmitter of the optical transmitters that is scheduled to transmit during the time period. A second optical signal is inserted into the first optical signal during the time period, the second optical signal having at least a non-zero power portion.

The present invention discloses a high-precision and large-dynamic-range fault monitoring device and method for a WDM-PON. The monitoring device includes a WDM-PON optical network system and an optical network monitoring system. The optical network system includes an OLT I, a feeder fiber II, a 1n AWG III, a branch fiber IV, and an optical network unit V The optical network monitoring system includes an FP laser, a coupler, an optical coupling device, a photodetector, a signal acquisition and processing device, and an optical feedback device, where the FP laser is connected to the coupler; a large-coupling-ratio output end of the coupler is connected to an input end of the optical coupling device, and a small-coupling-ratio output end of the coupler is connected to an input end of the photodetector; the optical coupling device is installed on the feeder fiber II.

In one embodiment, a first group of splitters receives a group of signals from a group of transmitters. Each splitter in the first group of splitters splits a signal into a plurality of signals that are sent to a plurality of multiplexers. A multiplexer in the plurality of multiplexers receives one of the plurality of signals from each splitter in the group of splitters and multiplexes the received one of the plurality of signals into a multiplexed signal. The multiplexer sends the multiplexed signal through a single connection in which upstream signals are sent to a group of nodes and downstream signals are received from the group of nodes. A de-multiplexer de-multiplexes the multiplexed signal into the group of signals and sends the group of signals to the group of nodes via a second group of splitters that are connected to the group of nodes.