Abstract: A 2×2 optical multi-input-multi-output (MIMO) demultiplexer is disclosed. A first optical phase shifter applies a first relative phase shift between a first pair of optical transmission paths that are received from MIMO inputs, and a first 2×2 optical coupler combines the first pair of optical transmission paths and outputs a second pair of optical transmission paths. A second optical phase shifter applies a second relative phase shift between the second pair of optical transmission paths, and a second 2×2 optical coupler combines the second pair of optical transmission paths and outputs a third pair of optical transmission paths. A third optical phase shifter applies a third relative phase shift between the third pair of optical transmission paths, and a third 2×2 optical coupler combines the third pair of optical transmission paths and outputs a fourth pair of optical transmission paths, which are output by a pair of MIMO outputs.

Abstract: A block processing method, node and medium are provided. The method includes: determining, in a metro transport network, Ethernet or flexible Ethernet, 64B/66B blocks of a forward error correction (FEC) codeword with errors that cannot been corrected; replacing all of the 64B/66B blocks in the FEC codeword with error control blocks, or replacing each invalid 64B/66B block in the FEC codeword with an error control block.

Abstract: The invention relates to a communication device comprising a docking station and a central processing unit. The docking station comprises a plurality of photoreceptors and a plurality of light sources interjacent with the photoreceptors. The plurality of photoreceptors and the plurality of light sources are suitable for visible light communication (VLC). The central processing unit is configured for obtaining an initialization signal, selecting a portion of the plurality of light sources of the docking station, ordering an emission of a pairing signal, obtaining a response signal, and ordering a pairing of the terminal with a portion of the plurality of photoreceptors of the docking station and with a portion of the plurality of light sources of the docking station.

Abstract: A wireless device and methods for handling wake-up signaling is presented. The wireless device is configured to receive a wake-up signal comprising wake-up information and authentication information, determine whether the wake-up signal is intended for the wireless device based on the wake-up information, and determine whether the wake-up signal is authentic based on the authentication information. Upon determining that the wake-up signal is intended for the wireless device and determining that the wake-up signal is authentic, the wireless device is further configured to initiate wake-up of radio circuitry comprised in the wireless device. Related computer program, computer program product and carrier are also described.

Abstract: The present disclosure discloses a protection switching method and a node. The method can include: receiving, by an intermediate node, a first protection switching request message sent by an upstream neighboring node, where the first protection switching request message is used to request to activate a first protection path, and the intermediate node is a node on the first protection path; determining, by the intermediate node, that the first protection path needs to occupy N1 timeslots, and selecting N1 timeslots for the first protection path from N2 available timeslots in a preset order; and sending, by the intermediate node, a second protection switching request message to the downstream neighboring node, where the second protection switching request message is used to request the downstream neighboring node to complete a cross-connection, on the first protection path, between the downstream neighboring node and the intermediate node based on the first group of timeslots.

Abstract: A system and method is disclosed in which circuitry of a first controller of a first node on a first path within a transport network receives a first signal indicating a failure within the first path from a second controller. The first node is an end node of the first path. A first client signal failure clear signal is received from a second node upstream of the first node on the first path. The first client signal failure clear signal indicates that a non-restorable fault has been resolved such that the first path can be considered for carrying data traffic. The non-restorable fault is a failure at the source. Subsequent to receiving the first signal indicating the failure within the first path, a backward defect indication clear signal is transmitted to the second node, the backward defect indication clear signal indicating an absence of a failure in the first path.

Abstract: The present disclosure relates to a signal processing system applied to remove OTDR noise, comprising: an analog-to-digital converter, a laser and driving unit, a sequence accumulator, a preprocessing counter, a pulse generator, a dual-port memory, a self-adaptive filter, an event decision device, and a preprocessing data decision device. The self-adaptive filter reads preprocessing data from a read-only port of the dual-port memory, and performs noise processing on the read preprocessing data by using a self-adaptive filtering method of wavelet transform. The event decision device performs an event decision on the filtered data output from the self-adaptive filter; The preprocessing data decision device decides whether a certain set of preprocessing data in m groups of preprocessing data is correct data or high-signal-to-noise data according to the difference of the m groups of preprocessing data after passing through the event decision device.

Abstract: Disclosed in some examples, are optical devices, systems, and machine-readable mediums that send and receive multiple streams of data across a same optical communication path (e.g., a same fiber optic fiber) with a same wavelength using different light sources transmitting at different power levels—thereby increasing the bandwidth of each optical communication path. Each light source corresponding to each stream transmits at a same frequency and on the same optical communication path using a different power level. The receiver differentiates the data for each stream by applying one or more detection models to the photon counts observed at the receiver to determine likely bit assignments for each stream.

Abstract: A protection path determination method and apparatus based on an elastic optical network are provided. The method includes: searching a virtual working topology for a virtual working link satisfying a condition on receipt of a routing request of a target service; updating a residual bandwidth of the virtual working link if the virtual working link is found; otherwise, creating a working link for the target service and creating a virtual working link in the virtual working topology; searching a virtual protection topology for a virtual protection link satisfying a condition according to a shared path protection mechanism; updating a residual bandwidth of the virtual protection link if the virtual protection link is found; otherwise, creating a protection link for the target service according to the shared path protection mechanism and creating a virtual protection link in the virtual protection topology.

Abstract: Systems and methods for characterizing an optical fiber performed in part by an optical node in an optical line system include performing one or more measurements to characterize the optical fiber with one or more components at the optical node, wherein the one or more components perform functions during operation of the optical node and are reconfigured to perform the one or measurements independent of the functions; and configuring the optical node for communication over the optical fiber based on the one or more measurements. The one or more components can include any of an Optical Service Channel (OSC), an Optical Time Domain Reflectometer (OTDR), and an optical amplifier. The configuring can include setting a launch power into the optical fiber based on the one or more measurements.

Abstract: The present disclosure provides an optical equalizer for photonics system in an electric-optical communication network. The optical equalizer includes an input port and an output port. Additionally, the optical equalizer includes a filter having a number of stages coupled to each other in a multi-stage series with an output terminal of any stage being coupled to an input terminal of an adjacent next stage while the input terminal of a first stage of the multi-stage series being coupled from the input port. Each stage includes a tap terminal configured to pass an optical power factored by a coefficient of multiplication from the corresponding input terminal of the stage to a tap-output path characterized by a corresponding phase delay. Furthermore, the optical equalizer includes a combiner configured to sum up the optical powers respectively from the number of tap-output paths of the multi-stage series to the output port.

Abstract: Methods, systems, and apparatus for communicating over a radio link by devices with broadband connectivity are disclosed. In one aspect, a telecommunications device includes a first transceiver, a second transceiver, and a state monitor. The first transceiver communicates over a broadband link. The second transceiver communicates over a radio link. The radio link is a Low-Power Wide-Area Network (LPWAN) link. The state monitor includes one or more processes that monitor a state of the telecommunications device, and in response to the state of the telecommunications device being one of a plurality of pre-specified states, transmit, using the second transceiver, data specifying the state of the telecommunications device over the radio link.

Abstract: Communication apparatus includes multiple interfaces configured to be connected to respective links in a packet data network. Switching circuitry in the apparatus is coupled between the interfaces and is configured to receive, via a first interface among the multiple interfaces, an adaptive routing notification (ARN) requesting that a specified flow of packets from a given source to a given destination in the network be rerouted. The switching circuitry is configured, upon verifying that the first interface serves as an egress interface for the packets in the specified flow, to reroute the specified flow through a different, second interface among the multiple interfaces when there is an alternative route available in the network from the second interface to the given destination, and after finding that there is no alternative route available from any of the interfaces to the given destination, to forward the ARN to a plurality of the interfaces.

Abstract: A method and a device are provided for processing data in an optical network. The method includes the steps of events of a login scan are recorded by a first optical network element; the events are conveyed to a second optical network element; and the events are processed by the second optical network element. A communication system is described that includes the device.

Abstract: A device is provided that mitigates the effects of an optical network unit (ONU) that is in a rogue state. A main processor is arranged as part of a monolithic semiconductor chip, the main processor configured to process signals from an optical telecommunication connection. A laser driver controls a laser coupled to the laser driver. Hardware logic is arranged as part of the monolithic semiconductor chip and arranged physically separate from the main processor. The hardware logic independently effects the laser driver to turn the laser off or reduce power output of the laser significantly to mitigate the effects of the ONU in the rogue state.

Abstract: Powering an active/splitter and providing information to ONUs to cause adjustments to ONU operating wavelengths. An ONU may identify the port of a splitter to which the ONU is connected in order to make wavelength adjustments. Various techniques enable the ONU to identify from which port the ONU is receiving signals, such as a splitter that splits signals to ONUs in a cable network and signals to one or more ONUs the port to which it is connected. The splitter may lack electrical power and may perform the signal function by harvesting optical power from optical power provided to the splitter. In this manner, an active splitter may behave passively with respect to powering components in the absence of electrical power.

Abstract: A node (20, 25) for a single fiber bidirectional WDM optical ring network has a first optical protection switch (100) having first and second ports for coupling to the single fiber bidirectional ring, while providing a pass through optical path for wavelengths on the bidirectional ring. A further port is coupled to an external optical path. In operation the switch couples optically bidirectional selected wavelengths between the external optical path and either of the first and second ports selectively, according to an indication of a fault on the ring, so as to use different portions of the bidirectional ring respectively as working path and protection path. This combines coupling wavelengths with the ring, with the selection of protection or working path, which simplifies the optical equipment, and upstream and downstream optical delays can be symmetrical.

Abstract: The disclosure provides a method and device for detecting rogue behaviour. The method comprises: for the upstream optical signal of each Passive Optical Network (PON) port, an Optical Line Terminal (OLT) constructs a short timeslot and transmits it via an optical transceiver; the OLT controls the optical transceiver to conduct a first Signal Detect (SD) sampling detection on the upstream optical signal according to the short timeslot to obtain a first detection result; the OLT judges, according to the first detection result, whether the upstream optical signal is valid; if so, the OLT constructs a long timeslot and transmits it via the optical transceiver, and controls the optical transceiver to conduct a second SD sampling detection on the upstream optical signal according to the long timeslot to obtain a second detection result; and the OLT determines, according to the second detection result, whether the current PON port is experiencing rogue behaviour.

Abstract: A system and method for connectivity configuration of a network node permits an optical signal to be passed through the node and shifted from a first connector position to a second connector position that is offset from the first connector position. The shifted optical signal permits a number of distant nodes in the network to be reached with a direct optical connection, which can be configured to be bidirectional. The disclosed connectivity configuration reduces the cabling requirements for the network and simplifies the interconnections.

Abstract: A method and network include receiving a Time Division Multiplexing (TDM) connection; determining information in overhead of the TDM connection; and if match/action rules defined by controller exist for the TDM connection, establishing the TDM connection based on matching an associated rule in the match/action rules. A Software Defined Networking (SDN) controller is configured to receive a request from a node related to a new TDM connection in the network; determine one or more routes in the network for the new TDM connection; determine match/action rules for the one or more routes at associated nodes of the one or more nodes; if the one or more routes include at least two routes, determine a group table at associated nodes of the one or more nodes to distinguish between the at least two routes; and provide the match/action rules and the group table to the associated nodes.

Abstract: A testing tray includes a receiving member and a connector. The receiving includes a tray and a latching member. The tray includes a bottom wall, a peripheral sidewall protruded from the bottom wall, a resisting member and a guide groove. The resisting member includes a resisting portion and two elastic portions coupling the resisting portion with the peripheral sidewall. The tray includes at least one latching portion protruded from the peripheral sidewall. The latching member includes a sliding portion slidably mounted on the bottom wall to cover the guide groove and an elastic member located between the sliding portion and the bottom wall. The connector includes a fixed member detachably mounted on the at least one latching portion and a conducting member detachably mounted on the fixed member. The conducting member is capable of coupling the electronic device with a testing device.

Abstract: A system and method for connectivity configuration of a network node permits an optical signal to be passed through the node and shifted from a first connector position to a second connector position that is offset from the first connector position. The shifted optical signal permits a number of distant nodes in the network to be reached with a direct optical connection, which can be configured to be bidirectional. The disclosed connectivity configuration reduces the cabling requirements for the network and simplifies the interconnections.

Abstract: A network apparatus used in an optical network is disclosed. The network apparatus includes one or more first tunable and temperature controlled (TTC) lasers, one or more transmitters each of which is connected to one of said one or more TTC lasers, one or more second TTC lasers, one or more digital signal processing (DSP) transponders (TPNDs) each of which is connected to one of said one or more second TTC lasers, one or more receivers, and a controller to control said one or more transmitters and said one or more DSP TPNDs, wherein said one or more transmitters defragment an optical access spectrum, and said one or more DSP TPNDs exploit a newly available spectrum. Other apparatuses, systems, and methods also are disclosed.

Abstract: The disclosure relates to a method and device for detecting a fault of signal processing equipment and an optical interface board on line. The signal processing equipment includes n function modules F1, F2, . . . Fn, and n fault detecting points T1, T2, . . . Tn for determining whether there is a fault in said n function modules, wherein n is a natural number. When the detecting result of said detecting point Ti indicates there is a fault in the function module Fi, the corresponding detecting points of other function modules directly associated with the function module Fi are detected continuously, and the reason of the fault is determined according to all the fault function modules. The present disclosure divides the equipment or the board into different modules in accordance with functions, a fault detecting point being set in each module.

Abstract: A method and arrangement in an Optical Network Terminal, ONT for monitoring the state of an Optical Distribution Network, ODN, in a Passive Optical Network, PON, is provided. The ONT receives an optical signal, from an Optical Line Terminal, OLT, having optical power, Po,sat, causing a Semiconductor Optical Amplifier, SOA, comprised in the ONU, to reach a saturated state. One or more parameters are measured. The parameters relates to the power provided from a power source to the SOA during a predefined time period, where the SOA is in a saturated state during the predefined time period. Information relating to the measured parameters are provided to the OLT and thereby enabling the OLT to compare the current state of the ODN to a previously measured reference state of the ODN.

Abstract: The embodiments disclosed herein provide a mechanism for sharing protection resources in an arbitrary network topology involving pre-computing the protection resources so that data-plane-based protection can be used to activate the protection resources upon detection of a failure, thus, providing faster switching times than typical control-plane-based solutions. This is accomplished by configuring a mesh network to include, for a working path in the network, one or more protection paths with the same end nodes as the working path, where each protection path includes at least one intermediate node that is not part of the working path. The intermediate node accepts a protection request from one of the end nodes and determines whether a local resource for a protection path is available.

Abstract: An optical transceiver that reduces the EMI radiation leaked therefrom is disclosed. The optical transceiver includes a top cover and the bottom base to form a cavity into which a TOSA, a ROSA, and a circuit are set. The top cover provides a combed structure in a rear portion thereof, where the combed structure has a plurality of fins with a distance preferably less that quarter wavelength ?/4 of the noise wavelength to be reduced. The combed structure operates as a short stub for the electromagnetic wave traveling longitudinally in the cavity.

Abstract: An apparatus and method for fault indication and localization in a Passive Optical Network (PON) comprising a multistage power splitter (100, 200, 300) with at least one 1:N splitter (120, 221, 222, 321, 322) followed by N items of 2:M splitters (131, 132, 231-233, 331-336), wherein N and M are integers greater than 1. The apparatus also comprises an Optical Time Domain Reflectometry (OTDR) device (110, 210, 310) capable of inserting an OTDR signal into the power splitter (100, 200, 300), and adapted to insert the OTDR signal between the first stage of the at least one 1:N splitter (120, 221, 222, 321, 322) and the second N items of 2:M splitters (131, 132, 231-233, 331-336).

Abstract: An arrangement at a Remote Node, a Remote Node, a Central Office, a WDM-PON and a method in an arrangement at a Remote Node, and a method in a Central Office are provided for supervision of the WDM-PON. The arrangement comprises at least one filter connected to the feeder fiber links and adapted to separate a data signal and an original OTDR signal received on either of the feeder fiber links. Further, the arrangement comprises a first splitter adapted to receive, from the at least one filter, the original OTDR signal, to split the original OTDR signal into a plurality of OTDR sub-signals and to output, to an N*M AWG, the plurality of OTDR sub-signals. The at least one filter is further adapted to output the original OTDR signal to the first splitter and to output the data signal to the AWG, thereby enabling supervision of the WDM-PON.

Abstract: An arrangement in a node in a WDM-PON and a method therein for supervision of the WDM-PON are provided. The arrangement comprises X splitters of splitting ratio 1:Y, each splitter having one input and Y outputs such that X*Y equals N, wherein X, Y, N are integers. The one input of each of the X splitters is configured to receive an Optical Time Domain Reflectometry, OTDR, signal and to split the received OTDR signal into Y OTDR sub-signals such that a total of N OTDR sub-signals are outputted from the X splitters. The arrangement further comprises an N*N Arrayed Waveguide Grating, AWG, and a first filter configured to mix a feeder signal comprising data communication from an Optical Line Termination, OLT, with one of the N OTDR sub-signals. One input of the AWG is configured to receive the mix of the feeder signal and the one OTDR sub-signal, and the remaining N-inputs of the AWG are each configured to receive a respective one of the N-remaining OTDR sub-signals.

Abstract: The invention discloses a system, a method and an apparatus for optical network protection. The system includes: an output control apparatus for obtaining protection mode information configured by a system and controlling an input signal to be output from a set line corresponding to said protection mode information; and a detection control apparatus for detecting powers of signals transmitted on an active line and on a standby line, if it is determined that the active line is abnormal and the standby line is normal according to detection results, then controlling the input signal to be output from a protection line corresponding to the protection mode information; if it is determined that the active line is normal, or that the active line and the standby line are abnormal according to the detection result, then controlling the input signal to be output from a set line corresponding to the protection mode information.

Abstract: An Ethernet-based transmission system using a dying gasp according to the present invention includes an SMPS for supplying power to an Ethernet-based lower level system, detecting a state of a power fault, and outputting a dying gasp alarm signal. A CPU receives the dying gasp alarm signal, and generates and transmits an alarm packet. A PHY chip receives the alarm packet, and uplinks the alarm packet so that the alarm packet is transferred to a higher level stage. An L3 switch receives the alarm packet and determines whether a power fault has occurred in the lower level system. Accordingly, the present invention applies a dying gasp to an Ethernet-based or EPON-based transmission system and is then capable of generating and transmitting an alarm packet so that when a power fault occurs, a device in a higher level network can rapidly determine the occurrence of the power fault.

Abstract: A device may include a component, a first switch, a repeater, and a second switch. The component may configure optical paths between ports. The component may comprise a first pair of optical ports connected to a first pair of optical fibers, and a second pair of optical ports connected to a second pair of optical fibers. The first switch may be configured to output one of two optical signals received by the first pair of optical ports from the first pair of optical fibers. The repeater may reshape or amplify the outputted optical signal. The second switch may be configured to direct the reshaped or amplified signal to one of the second pair of optical ports.

Abstract: An apparatus and method for monitoring an optical line is provided. The optical line monitoring apparatus may include a comparison unit to extract first identification information about an optical network terminal (ONT) from reflected data that is reflected and received from the optical line, and to compare the extracted first identification information to predetermined second identification information about the ONT, and a processor to analyze a state of the optical line using the reflected data when the first identification information is identical to the second identification information.

Abstract: System and method embodiments are provided herein to obtain minimum or optimal spare capacity allocation (SCA) using partial disjoint paths (PDP) for bi-connected network topology. Both an integer linear programming (ILP) optimization model and an approximation algorithm, referred to herein as Successive Survivable Routing (SSR), are formulated for resolving the SCA with PDP. The embodiments include assigning a working path and a primary backup path on two disjoint routes between two end nodes, and assigning a plurality of secondary backup paths that are partially disjoint and that each pass through one fiber cut group on one of the two disjoint routes and all remaining fiber cut groups on the other one of the two disjoint routes. Each of the fiber cut groups includes all fiber cut pairs on both disjoint routes that have the same effect of interrupting a flow on both disjoint routes.

Abstract: Methods, algorithms, architectures, circuits, and/or systems for determining the status of parameters associated with optical transceiver operation are disclosed. The method can include (a) accessing and/or monitoring parametric data for each of a plurality of parameters that are related to operation of the optical transceiver; (b) storing the parametric data in one or more memories; (c) comparing the parametric data for each of the plurality of parameters against at least one of a corresponding plurality of predetermined thresholds; and (d) generating one or more states indicating whether the parametric data for a unique one of the parameters has crossed one or more of the corresponding plurality of predetermined thresholds. The invention also relates to an optical triplexer, comprising the described optical transceiver.

Abstract: The disclosure discloses a de-mapping method and a device for an Optical Transport Unit (OTU) frame. The method includes: setting a receiving reference clock and a de-mapping path according to a highest priority of an OTU frame mapping mode of a local device (S102); receiving an OTU frame of an opposite device by using the receiving reference clock and the de-mapping path (S104); determining a de-mapping priority of the OTU frame according to a clock recovery result of the received OTU frame and a customer service alarm instruction (S106); and de-mapping the OTU frame of the opposite device by using a receiving reference clock and a de-mapping path corresponding to the determined de-mapping priority of the OTU frame (S108). By means of the present invention, the de-mapping efficiency and accuracy of the OTU frame in an optical transport network are improved.

Abstract: A node of an optical transport network system transmits optical wavelengths to an adjacent node through an operational line. An apparatus for protection switching of the optical transport network system transmits only an optical channel with a fault among a plurality of optical channels composed of flexible optical channel data units in an optical wavelength of the operational line, via a reserve line.

Abstract: A system comprising a first optical line terminal (OLT) comprising a first integrated optical network unit (ONU), and a first OLT transceiver, and a second OLT coupled to the first OLT, wherein the second OLT comprises a second integrated ONU, and a second OLT transceiver. Included is a first OLT comprising an optical transceiver, at least one processor coupled to the optical transceiver, wherein the processor working in conjunction with the optical transceiver is configured to determine an upstream wavelength corresponding to a second OLT, join, via a first ONU in the first OLT, the second OLT using the upstream wavelength corresponding to the second OLT, and transmit data to the second OLT by the first OLT via the first ONU, wherein the second OLT comprises a second ONU.

Abstract: A method for shared mesh restoration includes configuring a switch to allow sharing of a plurality of backup line cards across a plurality of node degrees associated with a reconfigurable optical add/drop multiplexer (ROADM). The switch is communicatively coupled to the ROADM. The method further includes configuring a number of backup line cards coupled to the switch. The number of backup line cards is based on determining a number of active backup lightpaths for each of a plurality of network failures associated with each of the plurality of node degrees of the ROADM, identifying which node degree and failure has the largest number of active backup lightpaths for all of the plurality of node degrees of the ROADM and for each of the plurality of network failures, and determining the number of backup line cards to configure based on the identified largest number of active backup lightpaths.

Abstract: A method for time synchronization on a passive optical network is disclosed, including: an optical line terminal (OLT) receives clock information sent by a first optical network unit (ONU); the OLT adjusts local time of the OLT according to the clock information, to implement clock synchronization between the OLT and the first ONU; the OLT sends the clock information to a second ONU, to implement clock synchronization between the second ONU and the OLT. The OLT in an embodiment of the present invention does not need to obtain clock signals from an upper network and the clock information does not need to be transmitted in a multi-level mode over a packet network; therefore, the precision of ToD can be greatly increased.

Abstract: The disclosure includes an apparatus comprising: a path computation element (PCE) comprising a processor configured to: receive a path computation element protocol (PCEP) path computation request from a path computation client (PCC), wherein the path computation request comprises an impairment validation request that directs the PCE to perform an impairment validation of a network path; after receiving the path computation request, compute a network path; and perform an impairment validation of the network path specified by the impairment validation request. In another embodiment, the disclosure includes a method comprising: sending, by a PCC a PCEP path computation request to a PCE, wherein the request directs the PCE to perform routing and wavelength assignment (RWA) and a first impairment validation of a network path, wherein the request comprises a type of signal quality of the network path which indicates the first type of impairment validation to be performed.

Abstract: A manner of providing for testing of access fibers in a PON (passive optical network) using OTDR (optical time-domain reflectometry). According to the invention, a PON includes an optical splitter module having one or more optical couplers that combines downstream light from 1×N optical splitter directing the output of an OLT (optical line terminal) and a cyclic AWG (arrayed waveguide grating) for transmission toward one or more ONUs (optical network units). The splitter module is preferably formed on a single semiconductor chip, such as a PIC (photonic integrated circuit) chip and may reside in an outside plant of the PON.

Abstract: Novel tools and techniques that can be used to detect network impairment, including but not limited to impairment of optical fiber networks. In an aspect, such tools and techniques can be deployed at relatively low cost, allowing pervasive deployment throughout a network. In another aspect, such tools and techniques can take advantage of a “dying gasp,” in which a network element detects a sudden drop in received optical (or electrical) power, resolution, etc. at short time scales and sends a notification across the network before the connection is completely compromised. In yet another aspect, some tools can include a supervisory function to analyze aspects of the dying gasp with the goal to determine network segments associated with an impairment and an estimate of the location of an impairment within the network.

Abstract: An optical transceiver having an integrated optical time domain reflectometer monitoring unit and methods for using the same are disclosed. The disclosure relates to an optical transceiver comprising an optical device comprising a wavelength division multiplexing system (WDM), a data signal driver, a data signal limiting amplifier, and an optical time domain reflectometer (OTDR) data processing module. Furthermore, the optical transceiver is particularly advantageous in an optical line terminal (OLT) and/or a passive optical network (PON). The integrated OTDR data processing module can protect the optical transceiver, ensure successful monitoring data, simplify network wiring and decrease system and network costs by decreasing the number of OTDR modules and WDM units.

Abstract: An optical transport network signal (OTM) comprising at least one optical channel is received at a first network equipment. The optical transport network signal (OTM) is processed to extract optical data units (ODUk) for each optical channel (OCh). There is detection for defects during the processing. The optical data units are retransmitted within optical transport units (OTUk) towards a second network equipment. When a defect has been detected, the retransmitting comprises inserting an optical channel transport unit alarm indication signal (OTUk-AIS) in an optical channel transport unit (OTUk) containing optical channel data units (ODUk) that are affected by the detected defect.

Abstract: A method for realizing an automatic protection switching of a transmission device is provided, and the method includes that: according to a received automatic protection switching trigger condition and information of each line sub-card, which are transmitted by a cross sub-card via a Time Division Multiplexing Fabric to Framer Interface (TFI5) frame, a control sub-card determines to execute protection switching, and sends a protection switching command to the cross sub-card; and the cross sub-card completes the protection switching action. A system for realizing an automatic protection switching of a transmission device is also provided. According to the technical solution of the present invention, the automatic protection switching of the transmission device in an Optical Transport Network (OTN) is achieved conveniently.

Abstract: An optical communication module includes a control unit, a nonvolatile memory and a volatile memory. The control unit monitors the optical communication module and repeatedly receives log information about a state of a host substrate from the host substrate. The control unit stores the log information in the volatile memory, together with a result of monitoring of the optical communication module. When a hazard signal indicating an abnormality relating to power supply from the host substrate is detected, the control unit writes, in the nonvolatile memory, the result of monitoring of the optical communication module and the log information from the host substrate.

Abstract: A wireless communications link comprising an RF link and a free space optics (FSO) link, a switch, an RF signal monitoring apparatus, an optical signal monitoring apparatus, alarm apparatus and a controller. The switch operates in a normal mode to aggregate the links to form a link aggregation group and to route traffic on the link aggregation group, a first protection mode to route traffic on the FSO link, or a second protection mode to route traffic on the RF link. The controller is arranged to receive an alarm signal and to generate and transmit a control signal to cause the switch to operate in the first protection mode when a first alarm signal is received, the second protection mode when a second alarm signal is received, and the normal mode when an indicator is received indicating that both signal quality parameters are above their threshold values.

Abstract: In a first aspect, the method and apparatus of the present disclosure can be used to periodically and/or intermittently place one or more ONUs attached to a PON in a power savings mode so that an OTDR test can be performed. While in the power savings mode, the ONUs temporarily suspend their transmitter function and power down their upstream lasers. In a second aspect, the method and apparatus of the present disclosure can be used to coordinate the performance of OTDR during one or more periodic or intermittent discovery slots used to detect and register ONUs recently connected to the PON. Because new ONUs are infrequently connected to the PON and ONUs already registered are not permitted to transmit during the discovery windows, OTDR can be performed during these windows without impacting, to a great degree, the normal operation of the PON.