A transmission apparatus executes a reception processing that receives a first alarm detected in a first transmission apparatus different from the own apparatus from among a plurality of transmission apparatus from a second transmission apparatus different from the own apparatus from among the plurality of transmission apparatus, executes a detection processing that detects a second alarm of the own apparatus, executes a mask processing that masks alarms including the first alarm received by the reception processing and the second alarm detected by the detection processing, and executes a sending processing that sends an alarm that is not masked by the mask processing from among the alarms to a third transmission apparatus different from the own apparatus and the second transmission apparatus from among the plurality of transmission apparatus or sending the alarm to a given apparatus different from any of the plurality of transmission apparatus.

An optical transmission apparatus includes a first transmitter configured to transmit a first optical signal in a first wavelength band and a second optical signal in a second wavelength band located next to the first wavelength band; a second transmitter configured to transmit a third optical signal in a third wavelength band located next to the second wavelength band and a fourth optical signal in a fourth wavelength band located next to the third wavelength band; and a processor coupled to the first transmitter and the second transmitter and configured to select the third wavelength band among the first wavelength band, the second wavelength band, the third wavelength band and the fourth wavelength band, and control the first wavelength band, the second wavelength band, and the fourth wavelength band based on the third wavelength band.

Adaptive bundling of capacity changes in an optical section includes, responsive to a request for a capacity change for a plurality of channels on an optical section, determining spectral loading of the optical section; determining a bundling of changes for the capacity change based on the spectral loading of the optical section; and performing the capacity change based on the bundling. The bundling includes a number of steps to achieve all of the capacity change and a maximum allowable amount of optical spectrum that can be changed in each step. The maximum allowable amount of optical spectrum that can be changed in each step can be adaptively determined based on the channel loading.

This disclosure relates to wavelength division multiplexed (WDM) passive optical networks (PON), and the transmission of point-to-point and broadcast or multicast channels from an optical line transmitter (OLT) to an optical network unit (ONU). There is provided a WDM PON (100) comprising: an OLT (105) coupled to a plurality of ONU (110a, 110b) using an optical fiber network (160); the OLT (105) having one or more WDM transceivers (115a, 115b) each arranged to receive multi-cast and point-to-point channels and wherein the or each WDM transceiver (115a, 115b) is arranged to transmit a said channel to a respective said ONU (110a, 110b) using a respective dedicated wavelength (λa, λb); an input channel switch (130a, 130b) associated with the or each WDM transceiver (115a, 115b) and arranged to selectively couple the input of the WDM transceiver to the multi-cast channels and the point-to-point channels (140,135); wherein the selected multi-cast or point-to-point channels are directly converted to the respective dedicated wavelength.

Provided are a method and device for mapping, multiplexing, demapping and demultiplexing data are provided. The method includes: mapping an Ethernet service data stream the rate of which is m*100 Gb/s sequentially into m Optical Payload Unit Sub-frames (OPUC) and multiplexing the m OPUC into an Optical Payload Unit Frame (OPUCm) the rate of which is m*100 Gb/s according to the way of byte interleave; and adding an Optical Channel Data Unit (ODU) overhead to the head of the OPUCm to obtain an Optical Channel Data Unit Frame (ODUCm) the rate of which is m*100 Gb/s, wherein the frame structure of the OPUC consists of 4 rows and 3810 columns; the frame structure of the OPUCm consists of 4 rows and 3810*m columns; and the frame structure of the ODUCm consists of 4 rows and 3824*m columns, wherein m is a positive integer. The present disclosure improves the spectrum efficiency of optical fibers and the systematic flexibility and the compatibility.

A multi-channel optical transmitter or transceiver includes transmitter optical subassembly (TOSA) modules optically coupled to and directly aligned with mux input ports of an optical multiplexer without using optical fibers. The optical multiplexer may include an arrayed waveguide grating (AWG) or a reversed planar lightwave circuit (PLC) splitter and may be located in a multiplexer housing having at least one side wall with input apertures aligned with the mux input ports. The TOSA modules may include a base supporting at least a laser, laser driving circuitry, and a lens for focusing the light output from the laser. Z-rings may be used to facilitate alignment and to mount the TOSA bases to the side wall of the multiplexer housing, for example, by laser welding.

An optically-switch data network includes an optical data bus, an optical wavelength bus, and multiple nodes connected by the optical data bus and the optical wavelength bus. A first node determines that it has communication information to transmit to a second node, and determines if a first subscription signal is present on the optical wavelength bus. The first subscription signal includes a target frequency. If the first subscription signal is not present on the optical wavelength bus, the first node injects an optical communication signal onto the optical data bus. The optical communication signal includes the communication information and a carrier wave. The carrier wave includes the target frequency. The second node receives the optical communication signal using the optical data bus. If the first subscription signal is present on the optical wavelength bus, injection of the optical communication signal onto the optical data bus is postponed.

A multi-channel optical transmitter or transceiver uses a reversed planar lightwave circuit (PLC) splitter as an optical multiplexer to combine optical signals at different channel wavelengths into a multiplexed optical signal. The reversed PLC splitter includes splitter output ports that are used as the mux input ports and a splitter input port that is used as the mux output port. The mux input ports may be optically coupled to respective transmitter optical subassembly (TOSA) modules with or without optical fibers. The PLC splitter includes wavelength independent branched waveguides that combine the optical signals received on the mux input ports into the multiplexed optical signal on the mux output port.

Spatial division multiplexing (SDM) allows multiple optical signals to be multiplexed onto a single optical link. Performance of SDM systems may be improved by monitoring performance metrics indicative of crosstalk between the spatially multiplexed signals and adjusting at least one transmission characteristic of one or more of the multiplexed signals in order to reduce the impact of the intermodal crosstalk.

In one embodiment, a method includes receiving, by a network controller and from a first node of a network, information associated with a data stream of the network and determining, by the network controller, a segmentation for the data stream. The segmentation includes a plurality of data segments and the plurality of data segments includes a first data segment. The method further includes determining, by the network controller, a data flow path for each of the plurality of data segments and determining, by the network controller, a first wavelength to assign to the first data segment. The first wavelength is one of a plurality of wavelengths spanning between the first node and a second node of the network.