A transparent optical overlay network (1) for providing end-to-end optical spectrum services over multiple transparent optical network domains (2) is described. The transparent optical overlay network (1) includes network domain interface devices, NDIDs, (3) provided at domain boundaries between adjacent transparent optical network domains (2). The network domain interface device, NDID (3), monitors and adjusts incoming optical signals received by the NDID (3) from a first transparent optical network domain (2-1) and monitors and adjusts outgoing optical signals output by the NDID (3) to an adjacent second transparent optical network domain (2-2). An overlay network controller (5) manages and controls the end-to-end optical spectrum services by controlling the NDIDs (3). The overlay network controller collects telemetry data (TDATA) for optical spectrum service characterization and SLA policing of the optical spectrum services.

According to an aspect of an embodiment, an optical line terminal (OLT) configured for downstream transmission in a passive optical network (PON) may comprise a processing device and a transceiver. The processing device may be configured to: generate a first downstream signal for transmission on a first channel at a first signal level, and generate a second downstream signal for transmission on a second channel at a second signal level. The first signal level may be greater than the second signal level. The PMD transmitter may be configured to transmit a combined downstream signal comprising the first downstream signal and the second downstream signal. The first transmit power of the first downstream signal may be selected based on a comparison to a second transmit power of the second downstream signal to facilitate reception of the first downstream signal from the combined downstream signal at an optical network unit (ONU).

This application provides a port detection method, an optical network device, and a passive optical network system, to quickly and accurately detect a port connected to an ONU, and improve efficiency of determining the port connected to the ONU. The method includes: an optical line terminal sends optical signals corresponding to all of N wavelengths to at least one optical network unit, where the N wavelengths are different from each other, and N is a positive integer; the OLT receives optical power values that are of the optical signals corresponding to all of the N wavelengths and that are sent by a first ONU, where the first ONU is any one of the at least one ONU; and the OLT determines, bases on the optical power values of the optical signals corresponding to all of the N wavelengths, information about an optical splitter port corresponding to the first ONU.

A method implemented by an optical line terminal (OLT) comprising a memory storage comprising instructions, a processor in communication with the memory, wherein the processor executes the instructions to generate a multi-rate downstream frame having a pre-defined length, the multi-rate downstream frame comprising a plurality of subframes that are each associated with a respective data rate, and a transmitter coupled to the processor and configured to transmit each subframe of the plurality of subframes of the multi-rate downstream frame at the respective data rate.

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.

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.

Example packet processing methods and devices are described. One example method includes that a first device identifies a received first packet through a first FlexE shim layer disposed in the first device. When identifying that the first packet is a flexible Ethernet (FlexE) packet, the first device performs timeslot mapping on the first packet, then encapsulates the first packet into a first gigabit passive optical network encapsulation mode (GEM) frame. One first identifier is selected by the first device from at least one identifier reserved for a FlexE service, and is allocated to the first GEM frame, where the first identifier is used to indicate that the first GEM frame is a GEM frame corresponding to the FlexE packet. The first device sends the first GEM frame that carries the first identifier.

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.

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 by 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-1D2), 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.