Abstract: A system has a first rack with a first set of servers and a first top of rack switch and a second rack with a second set of servers and a second top of rack switch. A first optical switch is connected to the first top of rack switch. A second optical switch is connected to the second top of rack switch and the first optical switch. The first optical switch and the second optical switch each employ wavelength selective switching.

Abstract: Optical devices in optical network exchange signals at a plurality of wavelengths via a plurality of pathways. Each of the optical devices is associated with a corresponding wavelength and includes multiple optical inputs/outputs (I/Os) to exchange signals at the corresponding wavelength via the plurality of pathways. During maintenance or failure of one of the optical I/Os in an optical device associated with a wavelength, communications are maintained in the optical network by switching communications at a same wavelength to another a different pathway and/or reforming the optical network using other wavelengths. For example, an optical network unit (ONU) may identify an error in a first wavelength associated with a first optical device included in an optical line terminal (OLT) and may forward data using a second wavelength associated with the other optical device included in the OLT.

Abstract: Systems and methods for method for data transport using secure reconfigurable branching units, including receiving signals from a first trunk terminal and a second trunk terminal by branching units. Broadcasting is prevented for secure information delivery by dividing, within the branching units, the signals from the first trunk terminal and the second trunk terminal into three or more sections. Signals may be received from a branch terminal by one or more branching units using a single branch fiber pair, and the signals from the branch terminals may be divided into three or more groups of optical channels, wherein at least e of the channels includes dummy light. The divided signals from the first trunk terminal, the second trunk terminal, and dummy light from the branch terminal may be merged, and the merged signal sent to the branch terminal.

Abstract: The present principles are directed to a transponder aggregator-based optical loopback in a multi-degree colorless, directionless, contention-less, reconfigurable optical add/drop multiplexer. The multiplexer includes a reconfigurable optical add/drop multiplexer section for performing connect operations for wavelength division multiplexing signals among all degrees. The section has a plurality of subsections. Each of the subsections corresponds to a respective one of the degrees and has an optical separator at an input side and an optical combiner at an output side. The multiplexer further includes a transponder aggregator section having a split-and-select switch-based transponder aggregator. The multiplexer also includes an optical line loopback having a connection path between the optical separator at the input side and the optical combiner at the output side of at least one of the subsections.

Abstract: An optical network for reassigning a carrier wavelength of an optical signal may include first and second optical nodes. The first optical node may be configured to transmit an optical signal along an optical path. The first optical node may also be configured to tune a carrier wavelength of the optical signal from a first wavelength to a second wavelength, according to a continuous function, to reassign the carrier wavelength of the optical signal. The second optical node may be configured to receive the optical signal and may include a feedback loop configured to adjust a wavelength of a reference optical signal to approximate the carrier wavelength of the optical signal.

Abstract: An optical fiber transmission system adapted to provide a remote passive identification of components deployed in said transmission system, wherein each component comprises an associated passive optical identification unit adapted to provide identification of a component type of the respective component on the basis of a received optical identification signature carried in an optical identification signal to said component.

Abstract: A wavelength selective switch includes a wavelength dispersive element that divides a beam input from an input port, a beam director that deflects a wavelength component, and a free space optical system that optically couple a input/output unit, the wavelength dispersive element, and the beam director. The free space optical system converts a shape of the beam such that a size extending in a second plane is relatively smaller than a size extending in a first plane, and to have a long axis and a short axis in a third plane. The long axis is inclined with respect to the first direction. The beam director includes a beam directing region in which a plurality of beam directing elements are arranged. The beam directing region deflects the respective wavelength components toward the predetermined output port. The beam directing region is provided to correspond to the shape of the beam.

Abstract: The present invention is directed to data communication system and methods. More specifically, various embodiments of the present invention provide a communication interface that is configured to transfer data at high bandwidth using PAM format(s) over optical communication networks. In various embodiments, amplitude and phase of the optical wave are modulated. There are other embodiments as well.

Abstract: A packet switch 40 comprises wavelength tunable optical transmitters 12, an optical switch fabric 42, optical detectors 30 and a controller 32. The transmitters 12 are arranged to receive at least one electrical signal packet to be switched and convert it into a corresponding optical signal packet at an input wavelength. The optical switch fabric 42 comprises an ingress stage 44 comprising wavelength selective routers 46 and an egress stage 50 comprising wavelength selective routers 54 and tunable wavelength converters 26 arranged to receive an optical signal at the input wavelength and to output an optical signal at an output wavelength. The controller 32 is arranged to set the input wavelength of a transmitter 12 and the output wavelength of a wavelength converter to configure a path across the switch fabric 42 connecting the transmitter 12 to a detector 30. A communications network router 90 comprises an input module 92, a packet switch 40, an output module 96 and a scheduler 94.

Abstract: The present invention provides a method and device for routing and wavelength assignment in an optical network. The method comprises: a topology step in which a topology network of the optical network is obtained; a route calculation step in which at least one route in the topology network is calculated, a first node and a last node of the route being predetermined, and the at least one route being part of all routes from the first node to the last node; and a wavelength assignment determination step in which for each node on the route, it is determined whether link attribute information of the node meets a predetermined constraint condition, if the predetermined constraint condition is met, the route is selected as a working route, and the method ends; if the predetermined constraint condition is not met, the method returns to the route calculation step.

Abstract: There is provided an optical transmission device, the optical transmission device including a wavelength selective switch configured to select a first optical signal having a first wavelength from an input signal of wavelength division multiplexing, an optical filter circuit configured to include an optical tunable filter having a pass wavelength that is tunable to a second wavelength of a second optical signal for passing therethrough, a splitter configured to split the input signal, a split signal split by the splitter being transferred to the optical filter circuit, and a coupler configured to couple the first optical signal selected by the wavelength selective switch and the second optical signal passed through the optical filter circuit.

Abstract: Methods and apparatus for monetizing a carrier network are provided. In an example, a wavelength service is captured from deployed network assets in a carrier network. A revenue factor (R), a capital expenditure factor (C), an operational expenditure factor (O), and a service level agreement factor (S) are selected from an analytic profile of the carrier network based on the wavelength service requirements. The R, C, O, and S factors are hexadecimal numbers, and can be weighted relative to each other. An index is calculated by concatenating the R, C, O, and S factors a prioritized order and converting the resultant hexadecimal number into a decimal number. The calculated index is assigned to the wavelength service. The index can be displayed, along with indices for other wavelengths on other paths, to a user in a graphical form.

Abstract: An optical functional device equivalent to a 2×2 Mach-Zehnder optical switch is produced by forming two 3 dB couplers and input/output waveguides on a substrate. Two optical phase modulation paths are formed on corresponding waveguides between 3 dB couplers. A channel region having an opposite electric polarity is formed between source and drain regions, having the predetermined electric polarity, formed on the substrate. The optical phase modulation path is insulated from the surrounding area and disposed above the channel region. Additionally, a control electrode (i.e. a gate region) subjected to high-density doping is formed above the optical phase modulation path. By applying an electric voltage having the predetermined polarity to the control electrode, the source region, and the drain region, it is possible to generate hot carriers, in proximity to the optical phase modulation path, so as to accumulate charges and change a refractive index, thus setting a desired light-wave input/output path.

Abstract: In an automatically switched optical network operating according to a wavelength plan, the wavelengths are assigned to an optical path based on availability, performance and SRS wavelength coupling reduction. First, the wavelengths are grouped in static bins based on their reach versus cost performance, and each bin assumes a ?Q of a middle wavelength. Then, the bins are moved into subsets of dynamic bins, constructed using bin constraints that account for the particulars of the respective optical path. The path is characterized taking into account the wavelength currently accessing at the end nodes, and the wavelength tandeming through the end nodes. Wavelength selection starts with the bins that satisfy the maximum number of constraints, and the wavelengths are checked sequentially against wavelength constraints; relaxed constraints are also applied when it is not possible to exactly satisfy one or more constraints.

Abstract: An intranodal reconfigurable optical add/drop multiplexer (ROADM) fiber management apparatus, and a system employing the apparatus. The apparatus comprises a plurality of ingress optical ports, a plurality of egress optical ports, and a plurality of optical interconnections interposed between ones of the plurality of ingress optical ports and ones of the plurality of egress optical ports. Each of the plurality of ingress optical ports corresponds to one of the plurality of egress optical ports. Each one of the plurality of ingress optical ports is optically coupled by way of the optical interconnections to at least one of the plurality of egress optical ports. Each one of the plurality of egress optical ports is optically coupled by way of the optical interconnections to at least one of the plurality of ingress optical ports.

Abstract: A reconfigurable optical add drop multiplexer (ROADM) includes local interfaces at which optical signals of different wavelengths are locally input into the ROADM, and a network interface configured to connect the ROADM to a network from which multiplexed optical signals of different wavelengths are transmitted to the network. In a first configuration, the ROADM is configured to transmit from the network interface to the network multiplexed signals of different wavelengths having a first minimum frequency difference. In a second configuration, the ROADM is configured to transmit from the network interface to the network multiplexed signals of different wavelengths having a second minimum frequency difference. The second minimum frequency difference is greater than the first minimum frequency difference. This arrangement reduces the power of four wave mixing cross products produced when optical signals of three wavelengths are multiplexed and transmitted from the ROADM to NZDSF or DSF fiber types.

Abstract: The disclosure describes implementations of an apparatus including a plurality of racks, wherein each rack houses a plurality of networking devices and each networking device includes a communication port. An optical circuit switch can be coupled to each of the plurality of communication ports in one or more of the plurality of racks, and a plurality of top-of-rack (TOR) switches can be coupled to the optical circuit switch. Other implementations are disclosed and claimed.

Abstract: The present invention provides a method and apparatus for automatically restoring node resource state in the Dense Wavelength Division Multiplexing Based Automatic Switched Optical Network (WSON) system. This method comprises the following steps: using each node in the WSON system as an initiation node and notifying the resource state of the initiation node to a neighboring node; the neighboring node comparing the received resource state of the initiation node with the resource state of the present end; and under the condition that the resource state of the initiation node and that of the neighboring node are inconsistent, according to the actual resource state, determining one of the initiation node and the neighboring node to be the node whose resource is occupied, and automatically releasing the resource of the node. The present invention also provides an apparatus for automatically restoring node resource state in the WSON system.

Abstract: A wavelength selective switch includes a light input/output unit that includes an input unit and an output unit of a wavelength multiplexed light arranged in a form of an array in a first direction, a light dispersing unit that receives the wavelength multiplexed light from the input unit and disperses the wavelength multiplexed light into signal wavelengths, a light condensing element that condenses the light dispersed into the signal wavelengths, and a light deflecting element array that deflects a signal light in the first direction and a second direction, that is orthogonal to the first direction, so as to switch the light of the signal wavelengths condensed by the light condensing element to a desired output unit.

Abstract: In an Optical Add-Drop Multiplexer, a drop section comprises a Wavelength Selective Switch (WSS) having at least one drop-port, the WSS being operative to couple a respective set of w (where w>1) wavelength channels from a received Wavelength Division Multiplexed (WDM) signal to each drop port. A respective 1:s power splitter is associated with each drop port. Each power splitter supplies the respective set of channels received from its drop port to each one of a corresponding set of coherent receivers. Each coherent receiver operates to receive a selected one of the respective set of channels.

Abstract: A Network Depth Limited Network Followed by Compute Load Balancing (ND-NCLB) can embed more cloud demands than the existing solutions. The inventive ND-NCLB, partitions the physical network into many sub-networks, and limits the mapping of cloud demands within one of the sub-networks to avoid over provisioning of resources.

Abstract: A communication network including a master switch and one or more local switches is provided with a loop-back test device for in line loop-back testing. The local switches convey communication traffic between one another using one or more channels of a transmission medium and configuration information using an out-of-band channel of the transmission medium that is separate from the channels used to convey the communication traffic. The master switch includes an application that generates configuration information including loop-back connection information for configuring the out-of-band channel using at least one loop-back test device, transmits the generated configuration information to the loop-back test device using the out-of-band channel of the transmission medium, and conducts loop-back testing using the out-of-band channel.

Abstract: A free space optical communication system (100) and method including: several optical beam expanders (414) for receiving incoming optical signals from ground sites and neighboring satellites; several optical preamplifiers (412) for preamplifying the received optical signals; one or more optical main amplifiers (404) for amplifying the preamplified optical signals; and an optical switch (408) for directing respective amplified optical signals to respective destinations via a respective optical beam expander. The respective amplified optical signals are inputted to a respective optical beam expander (414) for transmission to said respective destinations, as outgoing optical signals.

Abstract: An apparatus includes a bank of optical detectors, an input optical filter and a selector. The optical detectors are configured to output respective detection indications in response to detecting a presence of an optical signal. The input optical filter is configured to receive an input optical signal having an input wavelength, and to route the input optical signal to one of the optical detectors in the bank depending on the input wavelength. The selector is configured to select an output wavelength based on the detection indications of the optical detectors, and to cause generation and transmission of an output optical signal at the selected output wavelength.

Abstract: A wavelength selective switch and a wavelength selection method are provided. The wavelength selective switch comprises an input port, through which a light beam, including a plurality of optical signals having different wavelengths, is incident; a wavelength separation apparatus, including a Blue Phase Liquid Crystal (BPLC) device and configured to separate at least one optical signal from the light beam through the BPLC device; and at least one output port, configured to output the at least one optical signal separated by the wavelength separation apparatus respectively. With the wavelength selective switch and the wavelength selection method, a polarization-independent phase modulation can be realized without a depolarization device disposed in an optical path, which thereby simplifies an optical path, reduces an insertion loss, and lowers costs of the wavelength selective switch and even the entire optical communication system.

Abstract: An optical switching device includes a substrate having an optical waveguide thereon, and a phase transition pattern in or on a portion of the optical waveguide. The phase transition pattern includes a material that is configured to be switched between insulating and conductive states responsive to a stimulus. At least one conductive element on the substrate directly contacts the phase transition pattern to provide the stimulus to the phase transition pattern. Related fabrication methods are also discussed.

Abstract: The invention relates to a method for auto-configuring a wavelength selective switch (WSS) device having an output port and a plurality of input ports and coupled to a WSS controller. When connected to a WDM optical network, the WSS controller is programmed to utilize one or more optical channel monitors (OCM) coupled to the input and/or output ports to detect which of the wavelengths are present at the input ports. Wavelengths that are not detected on any input port are blocked by the WSS. Any wavelength detected as present at one and only one input port is switched by the WSS to the output port. If a wavelength is detected at two or more input ports, it is either blocked by the WSS at each of the input ports until user intervention, or is blocked at all but one of the input ports as defined by assigned port priorities.

Abstract: A wavelength selection switch system includes a wavelength selection switch including an input port and an output port, a nonvolatile memory in which configuration information for controlling an operation of the wavelength selection switch is stored, a high-speed memory in which reading and writing can be performed at a higher speed than in the nonvolatile memory and that stores a copy of the configuration information stored in the nonvolatile memory, and a control unit that controls an operation of the wavelength selection switch based on the configuration information read from the high-speed memory, wherein the control unit periodically reads the configuration information stored in the nonvolatile memory and writes a copy of the read configuration information to the high-speed memory.

Abstract: Due to demand for more network bandwidth, a need for multi-user optical network topologies has, and will continue to, increase. A method or corresponding apparatus in embodiments of the present invention provide for an availability determination tool for determining and displaying wavelength and subrate availabilities within a network. Benefits of embodiments of a tool include allowing a user to identify the availability and capacity of any wavelength on any network, via an interactive graphical user interface, such as by using three-dimensional representations. In one embodiment, the disclosed availability determination tool allows users to locate and view any combination of available wavelengths between nodes in an optical network topology, and generate graphical and tabular reports of the availability in order to maintain an efficient and organized method or apparatus for determining and controlling wavelengths in a network.

Abstract: The path selection and wavelength assignment to a selected path are performed by mapping the wavelength reach to the demand distribution (agile reach) resulting in a 50-60% increase in the network reach. The network reach is further increased (about 2.2 times) when on-line measured performance data are used for path selection and wavelength assignment. The connections may be engineered/upgraded individually, by optimizing the parameters of the entire path or of a regenerator section of the respective path. The upgrades include changing the wavelength, adjusting the parameters of the regenerator section, controlling the launch powers, mapping a certain transmitter and/or receiver to the respective wavelength, selecting the wavelengths on a certain link so as to reduce cross-talk, increasing wavelength spacing, etc.

Abstract: As described herein, a network device includes an optical circuit switch to perform circuit switching. The network device also has a plurality of removable line cards, each of which includes a packet switch. A switching manager automatically reconfigures the optical circuit switch based on a configuration of the removable line cards to maintain a guaranteed packet switching bandwidth between active line cards.

Abstract: An light input/output unit has at least three first ports, including a first input port for inputting light and a first output port for outputting light; at least three second ports, including a second input port for inputting light and a second output port for outputting light; and an alignment port for inputting and outputting alignment light. An optical axis of the input/output light of the first port and an optical axis of the input/output light of the second port differ from each other. The dispersive element changes the optical axes of input/output lights of the first and second ports by an angle corresponding to a wavelength. The light deflective element has a first part for directing the light from the first input port to the first output port and a second part for directing the light from the second input port to the second output port.

Abstract: A remote node (RN) comprises a downstream port, a wavelength multiplexer (WM) coupled to the downstream port and comprising ports for passing optical waves, an optical rotator coupled to the WM, and a mirror coupled to the optical rotator, wherein the WM, the optical rotator, and the mirror are part of a wavelength tuning scheme. An apparatus comprises a tunable transmitter, a polarization beam splitter (PBS) coupled to the tunable transmitter, a filter coupled to the PBS, a receiver coupled to the filter, a photodiode (PD) coupled to the PBS, and a processor coupled to the tunable transmitter and the PD. An apparatus comprises a tunable transmitter configured to transmit a first optical wave, a filter configured to receive a first reflected optical wave associated with the first optical wave, and a processor configured to tune the tunable transmitter based on the first reflected optical wave.

Abstract: One or more servers may receive an instruction to change a modulation format, associated with one or more optical channels, from a first modulation format to a second modulation format; provide the instruction to change the modulation format to a network device, associated with the one or more optical channels, to cause the network device to change the modulation format, associated with the one or more optical channels, from the first modulation format to the second modulation format; and determine that a license repository is to be updated based on receiving the instruction to change the modulation format. The license repository may store one or more licenses. The one or more servers may generate a license update instruction to update the license repository based on determining that the license repository is to be updated and output the license update instruction to cause the license repository to be updated.

Abstract: In order to realize a multiplexer/demultiplexer in which utilization efficiency of a frequency is high, wavelength characteristics of a transmission band is flat, the cost is low, the size is small, and a wavelength and a band are variable, the multiplexer/demultiplexer includes: first light branching means for branching inputted light into plurality of pieces of light and outputting the branched pieces of light; a plurality of light wavelength separating means for separating and outputting light outputted from the first light branching means for each of predetermined frequency bands; and an optical coupling means for making outputs having frequency bands different from each other among outputs from the light wavelength separating means gather and be outputted.

Abstract: Embodiments herein include a resilient add-drop module for use in one of multiple access subnetwork nodes forming an access subnetwork ring. The module comprises a dual-arm passive optical filter and a cyclic arrayed waveguide grating (AWG). The dual-arm passive optical filter is configured to resiliently drop any wavelength channels within a fixed band uniquely allocated to the access subnetwork node from either arm of the access subnetwork ring and to resiliently add any wavelength channels within the fixed band to both arms of the access subnetwork ring. The cyclic AWG is correspondingly configured to demultiplex wavelength channels dropped by the dual-arm filter and to multiplex wavelength channels to be added by the dual-arm filter. Configured in this way, the module in at least some embodiments advantageously reduces the complexity and accompanying cost of nodes in an optical network, while also providing resilience against fiber and node failures.

Abstract: Disclosed is a receptable optical amplifier. The receptable optical amplifier is detachably plugged in a switch device and has a pluggable type so as to be detachably plugged at a position in which a transceiver of the existing switch device is mounted. A body part 100 is provided with a placing part 112 therein, a controller 140 serving as a printed circuit board is mounted in the placing part 112, the controller 140 is provided with an EDF 160 at a lower portion thereof, and a passive and active device 150 at an upper portion thereof, and the receptable optical amplifier includes first and second isolators, a WDM coupler, a pumping LD, and a coupler equipped PD.

Abstract: In a network terminal (ONU) of an optical network near end crosstalk (NEC) is compensated by a digital generated cancellation signal. To establish a connection with another terminal (OLT) signals avoiding NEC are transmitted and the compensation is performed while the power of the transmitted signal is increased in steps.

Abstract: An optical signal switching device includes: first through third input ports; first through third output ports; first through third optical splitters: first through third optical couplers; first through third short wavelength pass filters respectively configured to pass the first wavelength band; and first through third long wavelength pass filters respectively configured to pass the second wavelength band. Each of the optical splitters splits a WDM optical signal input through a corresponding input port to be guided to a corresponding short wavelength pass filter and a corresponding long wavelength pass filter. Each of the optical couplers combines an output optical signal of a corresponding short wavelength pass filter and an output signal of a corresponding long wavelength pass filter to be guided to a corresponding output port.

Abstract: A network capable of being used in a datacenter is described. In some embodiments, the network can comprise a set of optical fiber rings, wherein each optical fiber ring carries data traffic on one or more wavelengths, and wherein each optical fiber ring is partitioned into multiple sectors. A reconfigurable optical add-drop multiplexer (ROADM) can be coupled to at least one optical fiber in each of at least two sectors. An electro-optical-switch can be coupled to each ROADM in each of the at least two sectors. A set of switches can be coupled to each electro-optical-switch in each of the at least two sectors. The set of switches can comprise a first layer of aggregation switches that is coupled to a second layer of edge switches, wherein the edge switches can be coupled to servers in a datacenter.

Abstract: A colorless, reconfigurable, optical add-drop multiplexer (a colorless ROADM) is disclosed. The ROADM may include a de-interleaver, a diffraction grating, and a lens. The de-interleaver may separate an input signal into a first output signal, comprising odd channels, and a second output signal, comprising even channels. The diffraction grating may receive the first and second output signals from the de-interleaver. The diffraction grating may separate each of the first and second output signals into individual channels. The lens may collimate the individual channels received from the diffraction grating.

Abstract: An apparatus includes a first optical switching complex, a second optical switching complex in optical communication with the first optical switching complex, and an optical add/drop module in optical communication with the first optical switching complex and the second optical switching complex. At least one of the optical switching complexes includes a wavelength selective switch that is configured to be arranged in a cascaded configuration that, when so configured, results in an increase in a number of available transmit and receive ports available per degree of the apparatus.

Abstract: The invention relates to a directionless and colorless reconfigurable optical add/drop multiplexer (ROADM) for a number of clients comprising: an add/drop interface for optical signals of at least one optical network, wherein each received optical signal is split by at least one optical splitter into optical signals which are applied to a downstream cross connector distributing the split optical signals to wavelength selectors of different clients, wherein each wavelength selector performs a wavelength selection of at least one wavelength from the distributed optical signals, wherein an optical signal having a selected wavelength (?) is applied to a client transponder of a client.

Abstract: An optical add/drop multiplexer including one or more optical drop multiplexers connected in free space or fused by optical fiber pigtails, a wavelength blocker with an input port connected to an output port of the optical drop multiplexer through the fusion of the fiber pigtails, one or more optical add multiplexers connected in free space or fused by fiber pigtails, a digital signal processor, an analog-to-digital signal converter, a digital-to-analog converter, and a plurality of electronic control and feedback loops for tuning and scanning an optical wavelength.

Abstract: Routing and bandwidth assignment of new paths of different bandwidths, occupying different numbers of adjacent frequency slots in a wavelength switched optical network, involves selecting a route, and assigning a set of adjacent frequency slots. The assignment can place wider bandwidth ones of the new paths at an opposite end of a spectrum of the available frequency slots, to an end where narrower bandwidth ones are placed. A size of sets of available adjacent slots remaining after the assignment is likely to be increased, compared to a conventional first fit assignment. A wider subsequent new path can sometimes be accommodated along all or some of the route and thus the blocking probability can be lowered. The selecting of which of the possible routes to use can be made dependent on which has more sets of available adjacent frequency slots, or which has a wider gap between occupied slots.

Abstract: Switching architectures for WDM mesh and ring network nodes are presented. In mesh networks, the switching architectures have multiple levels—a network level having wavelength routers for add, drop and pass-through functions, an intermediate level having device units which handle add and drop signals, and a local level having port units for receiving signals dropped from the network and transmitting signals to be added to the network. The intermediate level device units are selected and arranged for performance and cost considerations. The multilevel architecture also permits the design of reconfigurable optical add/drop multiplexers for ring network nodes, the easy expansion of ring networks into mesh networks, and the accommodation of protection mechanisms in ring networks.

Abstract: An optical network includes a multidimensional coder and modulator for handling multiple-in-multiple-out MIMO spatial lightpath properties and content of any specific supercarrier, a spatial mode multiplexer responsive to orthogonal frequency division multiplexing OFDM transmissions and the multidimensional coder, a spatial-spectral routing node coupled over a fiber link to the spatial mode multiplexer for performing switching granularity by a spatial mode reconnection, a multidimensional decoder and demodulator; and a spatial mode demultiplexer coupled over a fiber link to the spatial-spectral routing node and responsive to the multidimensional decoder and demodulator.

Abstract: There is provided a method of determining transmission quality of a path in an optical communication network system obtained by connecting a plurality of networks, the method including: acquiring a value representing transmission performance corresponding to a network condition of each of spans in the path in the optical communication network system; and determining the transmission quality of the path on the basis of the acquired value representing transmission performance corresponding to the network condition of each of spans.

Abstract: To facilitate routing and wavelength assignment (RWA) in an optical communications network having a given topology of associated nodes and links, a set of system characteristics associated with operating the optical communications network may be determined. Different sets of values may be selected for one or more parameters of an RWA algorithm defined for operating a set of services on the optical communications network, and associated sets of routes and wavelengths that may be assigned to the set of services via the RWA algorithm in accordance with the different sets of values and the set of system characteristics may be determined. The different sets of routes and wavelengths may be compared based on one or more fitness criteria and thereby selected between. A path computation engine of the optical communications network may then be provisioned with the selected set of values for the one or more parameters.

Abstract: A method and apparatus for controlling traffic in an optical network having a plurality of OLTs for communicating with a plurality of PONs. A traffic controller receives traffic information concerning current traffic volume and, preferably with reference to a rules database, calculates the number of OLTs required to support the current traffic volume. A separate determination may be made whether a network reconfiguration is permitted at this time. If a reconfiguration is permitted, the traffic controller configures a traffic control switch to route the PON traffic to an from only the calculated number of OLTs. The traffic control switch may be implemented using a voltage-controlled optical fiber coupling or electronically, routing the traffic as electrical signals to and from electro-optical converters associated with each PON. The OLTs to be used may be selected by the traffic controller.