Systems and methods are implemented at an Optical Add/Drop Multiplexer (OADM) node using virtual sections to provide sectional control over an optical link over a foreign-controlled optical network. The systems and methods include obtaining and storing a first power spectral density snapshot of an optical link, from an optical spectrum monitor and when the optical link is in a non-fault condition; responsive to detection of a fault on channels traversing the optical link, obtaining a second power spectral density snapshot at a receiving end of the optical link; analyzing the first power spectral density snapshot and the second power spectral density snapshot; and determining the fault is on the optical link based on the analyzing.

An automatic power reduction (APR) system for an optical network module, including: a multi-fiber interface including a plurality of ports adapted to be coupled to one or more multi-fiber connectors; a card processor operable to detect a loss of signal on an input port of the plurality of ports and comparing the power of an associated output port to an activation threshold received by the card processor; and a module processor operable to, in the event that the loss of signal is detected on the input port and the power of the output port exceeds the activation threshold, trigger the optical network module to execute an APR routine and attenuate spectrum associated with an affected port using a wavelength selective switch coupled to the plurality of ports.

Aspects of the present disclosure provide a technical solution that enables various passive optical network (PON) type infrastructures to coexist with dense wavelength division multiplexing (DWDM) network infrastructures. According to an embodiment, an optical communication network framework uses an optical coexistence topology to enable coexistence of PON type components and DWDM components. An optical coexistence system uses an optical coexistor to convey an upstream optical signal to one of an arrayed wave grating (AWG) of a DWDM system and an optical line terminal (OLT) of a PON by conveying unfiltered portions of the upstream optical signal to the OLT and filtered portions of the upstream optical signal to the AWG.

A remote node includes a first node input, a second node input, and an optical switch. The optical switch includes a first switch input optically coupled to the first node input, a second switch input optically coupled to the second node input, a first switch output switchably coupled to the first switch input or the second switch input, and a second switch output switchably coupled to the first switch input or the second switch input. The remote node includes a photodiode optically coupled to the second switch output, and a capacitor electrically coupled to the photodiode and the optical switch. When the first switch input is switchably coupled to the first switch output, the second switch input is switchably coupled to the second switch output. Light received by the second switch input passes out the second switch output to the photodiode. The photodiode charges the capacitor to a threshold charge.

A remote node includes a first node input, a second node input, and an optical switch. The optical switch includes a first switch input optically coupled to the first node input, a second switch input optically coupled to the second node input, a first switch output switchably coupled to the first switch input or the second switch input, and a second switch output switchably coupled to the first switch input or the second switch input. The remote node includes a photodiode optically coupled to the second switch output, and a capacitor electrically coupled to the photodiode and the optical switch. When the first switch input is switchably coupled to the first switch output, the second switch input is switchably coupled to the second switch output. Light received by the second switch input passes out the second switch output to the photodiode. The photodiode charges the capacitor to a threshold charge.

A communication system of a passive optical communication network includes an optical line terminal (OLT) system including a first OLT, a second OLT, and an OLT control device that controls the first OLT and the second OLT, a plurality of splitters that connect the first OLT and the second OLT with an optical communication path, and an ONU that is connected to each of the splitters with an optical communication path. The splitter distributes and outputs an optical signal transmitted from the OLT system to the ONU connected to the splitter and a succeeding device that is another splitter or the OLT system, and the OLT control device determines a distribution ratio at the splitter, the distribution ratio indicating a ratio between the intensity of the optical signal distributed to the succeeding device and the intensity of the optical signal distributed to the ONU.

An optical transmission apparatus of an embodiment is an apparatus for redundantly transmitting a multiplexed signal obtained by multiplexing N (N is an integer of 2 or greater) optical signals having different wavelengths, the apparatus including: a first demultiplexing unit to which a first multiplexed signal is input, the first demultiplexing unit configured to demultiplex the input first multiplexed signal into the N optical signals; N first detection units to which the N optical signals demultiplexed by the first demultiplexing unit are respectively input, each of the N first detection units configured to detect presence or absence of deterioration of a corresponding input optical signals of the input optical signals based on a signal level of the corresponding input optical signal; a second demultiplexing unit to which a second multiplexed signal is input, the second demultiplexing unit configured to demultiplex the input second multiplexed signal into the N optical signals; N second detection units to which the N optical signals demultiplexed by the second demultiplexing unit are respectively input, each of the N second detection units configured to detect presence or absence of deterioration of a corresponding input optical signal of the input optical signals based on a signal level of the corresponding input optical signal; and a selection unit configured to select, based on the detection result of presence or absence of deterioration of each of the optical signals by the first detection units and the second detection units, N optical signals having different wavelengths from either the optical signals demultiplexed by the first demultiplexing unit or the optical signals demultiplexed by the second demultiplexing unit.

An example system includes a first network device having first circuitry. The first network device is configured to perform operations including receiving data to be transmitted to a second network device over an optical communications network, and transmitting first information and second information to the second device. The first information is indicative of the data, and is transmitted using a first communications link of the optical communications network and using a first subset of optical subcarriers. The second information is indicative of the data, and is transmitted using a second communications link of the optical communications network and using a second subset of optical subcarriers. The first subset of optical subcarriers is different from the second subset of optical subcarriers.

A route switching device includes a first selection section for outputting a first main signal, a second selection section for outputting a first switching command signal, a first transmitter transmitting an inputted signal, a second transmitter, a first receiver, a second receiver, a first monitor for outputting an abnormality notification if an abnormality in a second main signal is detected, and outputting a first switching command notification if second information is included in a second switching command signal, a second monitor, and a third selection section for obtaining a second main signal from a selected receiver. The first selection section and the second selection section switches a selection destination when a first switching command notification is input. The second selection section outputs a switching command signal including second information when an abnormality notification is input. The third selection section switches a selection source when an abnormality notification is input.

Concepts and technologies for multi-lane optical transport network recovery are provided herein. In an embodiment, a system includes multi-lane optical transceiver. The multi-lane optical transceiver can include a transmitter optical sub-assembly, a receiver optical sub-assembly, and a controller that includes a processor and a memory that stores computer-executable instructions that, in response to execution by the processor, cause the processor to perform operations. The operations can include detecting an optical interruption event corresponding to an optical lane within a multi-lane optical path. The operations can further include instantiating an optical protocol alarm based on the optical interruption event. The operations can further include generating an optical protocol message based on the optical protocol alarm. The operations can further include instructing a peer multi-lane optical transceiver to alter optical transmission along the multi-lane optical path based on the optical protocol message.