Methods and systems for reducing power consumption in a multi-channel passive optical network (PON). A processor in the PON may monitor the channels in the multi-channel PON to detect a currently inactive channel, determine whether the detected channel has been inactive for an extended period of time, and deactivate the detected channel (by deenergizing transmitter(s) and/or receiver(s) associated with the detected channel) in response to determining that the channel has remained inactive for an extended period of time. The processor may re-activate the channel in response to determining that an optical signal has been reliably present on the channel for a sufficient period of time.

Systems and methods for delivering multiple passive optical network services are disclosed. One system includes a first optical transmission service comprising a common wavelength pair routed from a source to each of a plurality of subscribers and a second optical transmission service comprising a plurality of unique wavelength pairs, each of the unique wavelength pairs assigned to a subscriber among the plurality of subscribers. The system includes a splitter optically connected to first fiber carrying the first optical transmission service, the splitter including a plurality of outputs each delivering the first optical transmission service, and a wavelength division multiplexer connected to a second fiber, the wavelength division multiplexer separating each of the unique wavelength pairs of the second optical transmission service onto separate optical fibers. The system further includes a plurality of second wavelength division multiplexers optically connected to a different output of the plurality of outputs of the splitter and to a different one of the unique wavelength pairs from the wavelength division multiplexer, thereby combining a unique wavelength pair and a common wavelength pair onto a single fiber to be delivered to a subscriber.

This application discloses a bandwidth allocation method, an optical line terminal (OLT), an optical network unit (ONU), and a system, where the method includes receiving a bandwidth request from each ONU, where the ONU includes an ONU1, generating a bandwidth map (BWMap) message according to bandwidth requested by the ONU and bandwidth configured for the ONU, where the BWMap message includes a first allocation identifier (Alloc-ID1), a first time corresponding to the Alloc-ID1, a second allocation identifier (Alloc-ID2), and a second time corresponding to the Alloc-ID2, and both the Alloc-ID1 and the Alloc-ID2 are allocated to the ONU1 for use, and sending the BWMap message to each ONU. Therefore, a problem that a transmission delay does not satisfy a requirement when a passive optical network (PON) system is applied to mobile backhaul is resolved, a data transmission rate and data transmission efficiency are improved, and user satisfaction is improved.

In one embodiment, an apparatus is configured to perform mapping an interleaved bit stream into a sequence of 4-level pulse amplitude modulation (PAM4) labels according to a mapping scheme, with a respective PAM4 label including a least significant bit (LSB) and a most significant bit (MSB) respectively corresponding to a bit in the interleaved bit stream; transmitting a sequence of PAM4 symbols generated based on the sequence of PAM4 labels to the ONUs; and wherein, bits from respective one of the N codewords are assigned to LSBs of a first subset of labels, and to MSBs of a second subset of labels, with the first and the second subset of labels being determined based on the interleaving scheme and the mapping scheme and respectively comprising labels located N labels apart in the sequence of PAM4 labels.

An optical network system includes an optical line terminal, an optical splitter that is connected to the optical line terminal via one first optical fiber, and a plurality of optical network units that are connected to the optical splitter via respective second optical fibers. The plurality of optical network units communicate with the optical line terminal using an optical signal of a working wavelength uniquely assigned to each of them. The optical line terminal communicates with an optical network unit that is connected to the optical splitter using an optical signal of a working wavelength and an optical signal of a spare wavelength that is common to a plurality of optical networks.

The invention provides a method and apparatus for reconfiguring wavelength of the ONU. To be specific, the OLT sends a Deactivate_ONU-ID message to the ONU, the Deactivate_ONU-ID message including a reconfiguration flag, a new receive wavelength assigned for the ONU and a new transmit wavelength assigned for the ONU. After receiving the Deactivate_ONU-ID message from the OLT, the ONU discards the TC layer parameters related to the current wavelength channel, and determines whether the reconfiguration flag included in the Deactivate_ONU-ID message indicates the receive wavelength and the transmit wavelength of the ONU are required to be reconfigured. If so, then the ONU replaces its original receive wavelength and original transmit wavelength with its new receive wavelength and the new transmit wavelength included in the Deactivate_ONU-ID message, and enters initial state; and if not, then the ONU enters initial state directly.

Systems and methods for delivering multiple passive optical network services are disclosed. One system includes a first optical transmission service comprising a common wavelength pair routed from a source to each of a plurality of subscribers and a second optical transmission service comprising a plurality of unique wavelength pairs, each of the unique wavelength pairs assigned to a subscriber among the plurality of subscribers. The system includes a splitter optically connected to first fiber carrying the first optical transmission service, the splitter including a plurality of outputs each delivering the first optical transmission service, and a wavelength division multiplexer connected to a second fiber, the wavelength division multiplexer separating each of the unique wavelength pairs of the second optical transmission service onto separate optical fibers. The system further includes a plurality of second wavelength division multiplexers optically connected to a different output of the plurality of outputs of the splitter and to a different one of the unique wavelength pairs from the wavelength division multiplexer, thereby combining a unique wavelength pair and a common wavelength pair onto a single fiber to be delivered to a subscriber.

An integrated dynamic bandwidth allocation method and apparatus in a passive optical network (PON) are provided. The bandwidth allocation method performed by an optical line terminal (OLT) includes generating a service level agreement (SLA) table including an SLA required for calculation for bandwidth allocation corresponding to at least one service queue included in at least one optical network unit (ONU) connected to the OLT, calculating maximum allocatable bandwidths for respective predetermined cycles based on the generated SLA table, and, when a service queue requiring bandwidth allocation is present in the ONU, performing bandwidth allocation according to different bandwidth allocation methods based on a priority level of the service queue using the calculated maximum allocatable bandwidths.

Example embodiments describe an optical line terminal, OLT, configured to perform determining a fragmentation allocation for respective ONUs; and notifying, the respective ONUs, of the fragmentation allocation. Other example embodiments relate to an optical network unit, ONU, configured to perform receiving, from the OLT, fragmentation allocation for fragmenting one or more packets; processing the packets in accordance with the fragmentation allocation to obtain fragmented and unfragmented packets; and forwarding, to the OLT, the fragmented and unfragmented packets in accordance with the dynamic upstream allocation map.

A QTTH system based on multicore optical fiber mode division multiplexing, wherein comprising: an OLT end, a MDM-ODN and an ONU end, wherein the OLT end, the MDM-ODN and the ONU end are sequentially connected by an optical fiber; the MDM-ODN comprising a mode multiplexer and a mode demultiplexer, and the mode multiplexer and the mode demultiplexer are connected with each other through MCF, the OLT end comprising a classical signal transmitter, N DV-QKD units and N+1 mode convertors of the OLT end; the ONU end comprising N DV-QKD receivers, a classical signal receiver, N+1 mode convertors of the OLT end, 2N+1 PDs and one OC of the ONU end; the N DV-QKD receivers are respectively connected with the mode demultiplexer through PDs; the N+1 mode convertors of the OLT end are connected with the demultiplexer.