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.

Aspects of the present disclosure describe distributed fiber optic sensor systems, methods, and structures that advantageously enable/provide for the proper placement/assignment of sensors in the DFOS network to provide for high reliability, fault tolerant operation that survives fiber failures.

An optical element including a plurality of first circuits, the optical element includes a first cascade circuit in which one or more of first circuits are connected in cascade, a second cascade circuit in which one or more of first circuits are connected in cascade, and a combiner circuit configured to connect the first cascade circuit and the second cascade circuit. A first circuit included in the plurality of first circuits includes a first cascade structure in which N (N is an integer of 1 or larger) of 2-input and 2-output phase shifters and (N+1) of 2-input and 2-output couplers are alternately connected in cascade, and a first controller configured to control the N phase shifters in a direction in which optical input power decreases, the first controller being connected to one of two outputs of the first cascade structure.

A fault location in an optical cable at a long distance is easily measured and detected with low-cost equipment in a configuration in which an isolator is disposed in the vicinity of an optical amplifier for improved optical transmission performance and for stabilization. An optical amplifier has a configuration in which multiplexing/demultiplexing units as first WDM filters and that multiplex/demultiplex main signal light and OTDR light and (measurement light) for submarine cable fault measurement transmitted to a submarine cable in opposite directions from a transmission device side and a reception device side, transmit the multiplexed/demultiplexed main signal light to a main path passing through an isolators and an EDF, and transmit the multiplexed/demultiplexed OTDR light to a bypass path bypassing the isolators and the EDF are included on both sides of a set of the isolators and the EDF of the submarine cable.

A fault location in an optical cable at a long distance is easily measured and detected with low-cost equipment in a configuration in which an isolator is disposed in the vicinity of an optical amplifier for improved optical transmission performance and for stabilization. An optical amplifier has a configuration in which multiplexing/demultiplexing units as first WDM filters and that multiplex/demultiplex main signal light and OTDR light and (measurement light) for submarine cable fault measurement transmitted to a submarine cable in opposite directions from a transmission device side and a reception device side, transmit the multiplexed/demultiplexed main signal light to a main path passing through an isolators and an EDF, and transmit the multiplexed/demultiplexed OTDR light to a bypass path bypassing the isolators and the EDF are included on both sides of a set of the isolators and the EDF of the submarine cable.

An apparatus and a method for optically linking at least two AC and DC low voltage cascading power grids connecting at least two intelligent support boxes (ISB) each powered by two distinct AC standard power grid and separately powered by DC low voltage power grid with each grid is further linked by a cascading segments of optical cable grid, enabling two way control, operate and report electrical activity through plug in wiring devices (PWD) for supporting DC and AC plurality of connected/attached loads.

An apparatus and a method for optically linking at least two AC and DC low voltage cascading power grids connecting at least two intelligent support boxes (ISB) each powered by two distinct AC standard power grid and separately powered by DC low voltage power grid with each grid is further linked by a cascading segments of optical cable grid, enabling two way control, operate and report electrical activity through plug in wiring devices (PWD) for supporting DC and AC plurality of connected/attached loads.

Methods, systems, and apparatuses, among other things, may integrate one or more first alarms reported by routers and Ethernet switches with one or more second alarms reported by reconfigurable optical add/drop multiplexers (ROADMs) and optical transport network (OTN) network elements. Moreover, one or more troubleshooting actions may be performed based on the integrated first alarms and second alarms.

A photonics device includes a silicon wafer including a cathode region, an anode region, a trench region formed between the cathode region and the anode region, and a linear ridge formed between the cathode region and the anode region. A laser diode chip is mounted on the silicon wafer. A conductor layer disposed between the silicon wafer and the laser diode chip includes a first section disposed between the laser diode chip and the cathode region on a first side of the trench to electrically connect the laser diode chip to a cathode electrode of the photonics device and a second section disposed between the anode region and the laser diode chip on a second side of the trench to electrically connect the laser diode chip to an anode electrode of the photonics device.

A photonics device includes a silicon wafer including a cathode region, an anode region, a trench region formed between the cathode region and the anode region, and a linear ridge formed between the cathode region and the anode region. A laser diode chip is mounted on the silicon wafer. A conductor layer disposed between the silicon wafer and the laser diode chip includes a first section disposed between the laser diode chip and the cathode region on a first side of the trench to electrically connect the laser diode chip to a cathode electrode of the photonics device and a second section disposed between the anode region and the laser diode chip on a second side of the trench to electrically connect the laser diode chip to an anode electrode of the photonics device.