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: The present disclosure describes a reconfigurable optical add-drop multiplexer. The reconfigurable optical add-drop multiplexer includes a first optical equalizer to precompensate a received optical signal for optical filtering effects to produce a first compensated optical signal. A first interleaver, coupled to the first optical equalizer, separates the first compensated optical signal into an odd optical signal and an even optical signal. A plurality of wavelength selective switches processes the odd optical signal and the even optical signal. A second interleaver, combines the odd optical signal and the even optical signal to produce a combined optical signal. A second optical equalizer, coupled to the second interleaver, postcompensates the combined optical signal for optical filtering effects to produce an output optical signal.

Abstract: An optical signal switching device comprises a plurality of broadcast couplers (125), a plurality of wavelength selective modules (126), and optical connection means linking outputs of broadcast couplers to inputs of wavelength selective modules in order to route incoming optical signals received by said broadcast couplers to said wavelength selective modules. The wavelength selective modules are arranged in a plurality of groups (117, 118, 119), the wavelength selective modules of one group being connected at the output to a common neighboring node. The optical connection means (127, 41, 40, 42) are configured in such a way as to enable, for each of said broadcast couplers, the broadcasting of the incoming optical signal received by said coupler to at least one wavelength selective module of each group simultaneously.

Abstract: The present disclosure provides optimized configurations for a directionless reconfigurable optical add/drop multiplexer application. The present invention includes an add module with improved optical signal-to-noise through placing amplifiers prior to a multi-cast optical switch. The present invention includes various drop module configurations utilizing distributed gain, channel selective filters, and bi-directional configurations to reduce power consumption and complexity. Additionally, the present invention includes an integrated broadcast and select architecture.

Abstract: An apparatus comprising a network element (NE) configured to support routing-associated signal compatibility constraint information that is associated with the NE using Generalized Multi-Protocol Label Switching (GMPLS) and an open shortest path first (OSPF) routing protocol, wherein the signal compatibility constraint information comprises a modulation type list, a Forward Error Correction (FEC) type list, a bit rate range list, and an acceptable client signal list, and wherein the signal compatibility constraint information is associated with a resource block (RB) pool for a plurality of NEs. Also disclosed is a network component comprising a transmitter unit configured to transmit signal compatibility constraints via GMPLS OSPF routing, wherein the signal compatibility constraints comprise a modulation type list, a FEC type list, a bit rate range list, and an acceptable client signal list.

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: An optical transmission system for communicating between transmission devices includes a first pump light source that supplies a first pump light, a second pump light source that supplies a second pump light, an optical transmission line that propagates an optical signal between the transmission devices, and a plurality of couplers that form a plurality of zones in the transmission line, the first pump light source and the second pump light source being optically connected to different couplers of the plurality of couplers, the second pump light Raman-amplifying the first pump light in a zone in which the second pump light is input in the transmission line.

Abstract: A network component comprising a generalized multiprotocol label switching (GMPLS) control plane controller configured to implement a method comprising transmitting a message to at least one adjacent control plane controller, wherein the message comprises a Type-Length-Value (TLV) indicating Routing and Wavelength Assignment (RWA) information, wherein the TLV comprises a Node Attribute TLV, a Link Set TLV, or both, and wherein the TLV further comprises at least one sub-TLV indicating additional RWA information. A method comprising communicating an open shortest path first (OSPF) link state advertisement (LSA) message comprising a TLV with at least one sub-TLV to a GMPLS control plane controller, wherein the TLV comprises a Node Attribute TLV, a Link Set TLV, or both, and wherein the TLV further comprises at least one sub-TLV indicating RWA information.

Abstract: An optical switching device with a switch-and-select architecture uses a single multi-port optical channel router, such as a wavelength selective switch, as a bidirectional switching device. The optical switching device includes the multi-port optical channel router and optical circulators coupled to the input/output ports of the multi-port optical channel router. The optical circulators couple one or more output ports and one or more input ports of the optical switching device to the input/output ports of the optical channel router so that the optical channel router provides symmetric, bi-directional switching at an optical network node.

Abstract: A method and apparatus are provided for attenuating an optical beam. The method includes selecting a level of attenuation to be applied to the optical beam. A pattern of on-state and off-state pixels in a two dimensional spatial light modulator (SLM) is selected such that the pattern will modulate the optical beam to provide the selected level of attenuation. Finally, the optical beam is directed onto the SLM while tile pixels are arranged in the selected pattern. The pattern is periodic along a first axis and symmetric along a second axis along which an intensity distribution of die optical beam extends.

Abstract: In a wavelength selective optical switch device that disperses a WDM light beam according to their wavelengths. Dispersed light beams is applied to a wavelength selecting element. Incident light beams are separately reflected in different directions according to their wavelengths by use of the multi-level optical phased array. In the optical phased array, even when the number of multi levels is small, by setting the maximum phase shift amount of the phased array to be at least 1.5 ? and less than 2.0 ?, wavelength dependence is reduced, thereby reducing crosstalk. In this manner, the wavelength dependence, in turn, crosstalk can be reduced.

Abstract: Embodiments of the present application provide a method for an optical switch and an optical switch. The optical switch includes a light turning unit, configured to turn a plurality of light beams, where the light turning unit includes a plurality of MEMs grating beams, the plurality of light beams falls on the plurality of MEMs grating beams to form a plurality of light spots, one light spot falls on at least two MEMs grating beams, one grating beam bears a part of one light spot, and at least two MEMs grating beams in the plurality of MEMs grating beams are rotated in turn in batches, to reflect at least a part of a light spot to at least one preset emergent path.

Abstract: A network element (10) comprises: a first optical input section (1), a first optical output section (2), a second optical input section (3) and a second optical output section (4) a first and second insertion and extraction modules (30, 40), each of said insertion and extraction modules comprising a wavelength selection switch (31, 41), a first optical coupler (8) comprising two bidirectional branches (21, 22) respectively connected to the first selectable port of the first and second insertion and extraction modules, and a second optical coupler (11) comprising two bidirectional branches (23, 24) respectively connected to the second selectable port of the first and second insertion and extraction modules.

Abstract: In wavelength switching optical networks, the optical data being transmitted may be routed to different end points by switching the operating frequency of the laser. However, the phase noise of the laser source increases following a switching event. This increased phase noise can prevent the successful transmission of phase modulation formats which are sensitive to it. Accordingly, it is generally necessary to wait a short period before transmitting data. However, the period may be as long as the data packet being transmitted (e.g. 3 ?S), which is a limiting factor. The present application obviates this problem by including a radio frequency pilot tone with the data prior to modulation onto the optical carrier.

Abstract: A switch for switching optical signals. The switch includes a plurality of inputs, wherein each of the plurality of inputs receives one of a plurality of input signals, and at least one coupling element operably connected to two or more of the plurality of inputs and configured to combine at least two of the input signals into a combined output signal. The switch further includes a splitting element operably connected to the at least one coupling element and configured to demultiplex the combined output signal to produce a plurality of demultiplexed output signals. A control plane processor is operably connected to at least one of the plurality of inputs and is configured to determine a schedule for one or more devices operably connected to the plurality of inputs to transmit data bursts.

Abstract: A switch port device for transmitting and receiving optical bursts over an optical burst network. The switch port device includes a first end device interface configured to receive incoming data from a first end device and intended for a destination device, a processing device operably connected to the first end device interface and configured to control the modulation of the incoming data to a wavelength associated with the destination device to produce a modulated burst, an optical transmitter operably connected to the processing device and configured to transmit the modulated burst to an optical core, and an optical receiver operably connected to the processing device and configured to receive at least one incoming optical burst from the optical core.

Abstract: A Wavelength Division Multiplexing (WDM) multi-mode switching system and method and method provides concurrent switching in various switching modes including, but not limited to, an electronic packet switching (EPS) mode, optical circuit switching (OCS) mode, and optical burst switching (OBS) mode. Edge routers in the WDM multi-mode switching systems may provide a traffic management module that processes incoming data and routes the data for transmission in an electronic packet switching (EPS), optical burst switching (OBS), or optical circuit switching (OCS) modes via a WDM link.

Abstract: A system and method are disclosed for transporting deterministic traffic in a gigabit passive optical network. A system that incorporates teachings of the present disclosure may include, for example, an Optical Line Termination (OLT) for exchanging data traffic in a Gigabit Passive Optical Network (GPON) having a controller programmed to generate a timeslot schedule for transport of a desired bandwidth of constant bit rate (CBR) data traffic by selecting one or more timeslots from periodic frame clusters operating according to a GPON Transmission Convergence (GTC) protocol. Additional embodiments are disclosed.

Abstract: Additional bandwidth is provisioned to layer 2/3 networks by initially provisioning optical wavelength channels to meet incremental needs for additional capacity. When bandwidth requirements grow large enough, a wavelength-sized channel is provisioned to meet the bandwidth needs, and the previously provisioned optical wavelength channels are freed up to be reused for additional growth. The optical wavelength channels may be channelized VLANs mapped to resizable optical channel data units such as ODUflex units.

Abstract: An optical repeater formed in an optical passive component passively relays an incoming multiplexed optical signal. The repeater has an optical decoder decoding the multiplexed optical signal, and an optical encoder encoding an optical signal from a termination unit connected to the repeater. The repeater further includes a first optical path switch outputting an incoming multiplexed optical signal to the optical decoder and outputting the optical signal delivered from the optical decoder, a second optical path switch outputting the optical signal coming from the first optical path switch to the termination unit, and a third optical path switch outputting the optical signal coming from the second optical path switch to the encoder and outputting the optical signal delivered from the encoder.

Abstract: An apparatus comprising a path computation element (PCE) configured for at least partial impairment aware routing and wavelength assignment (RWA) and to communicate with a path computation client (PCC) based on a PCE protocol (PCEP) that supports path routing, wavelength assignment (WA), and impairment validation (IV). The PCEP comprises at least one operation selected from the group consisting of a new RWA path request operation and a path re-optimization request operation. Also disclosed is a network component comprising at least one processor configured to implement a method comprising establishing a PCEP session with a PCC, receiving path computation information comprising RWA information and constraints from the PCC, and establishing impairment aware RWA (IA-RWA) based on the path computation information and a private impairment information for a vendor's equipment.

Abstract: An optical communication apparatus of a wavelength division multiplexing transmission system has a transponder having a double-wavelength tunable transceiver and a transceiver including a switching controller, and a ROADM device having a device that copes with a colorless function and a directionless function and can operate in cooperation with the transponder.

Abstract: There is provided an optical transmission apparatus including: a plurality of wavelength selective switches including input ports, a transmission port, and monitor port used to output a light switched so that the light from the input port is monitored; a multiplexer to combine the lights output from the transmission ports of the plurality of wavelength selective switches; a monitor to monitor whether a same wavelength of the light output from the monitor port exists in wavelengths of the lights combined by the multiplexer; and a controller to control the wavelength selective switch so as to output, from the transmission port, the light switched to the monitor port in case that the same wavelength of the light output from the monitor port is absent in wavelengths of the lights combined by the multiplexer, based on a monitor result by the monitor.

Abstract: A large communication network suitable for nationwide or worldwide utilization. The present invention overthrows the conventional packet switching technologies with an all-optical network. The invention uses tunable laser sources to generate large number of highly stable narrow-band optical signals, each serving as a communication channel. With packet processing replaced by all-optical channels, the network become highly secure and scalable while harnessing the virtually unlimited capacity of fiber-optic. A large number of nodes (called area code nodes) are connected with all-fiber-optic links with all-optical switches. A routing algorithm provides one or more communication links from each area code node to every other area code node so that information never has to change carrier wavelength as it travels the network. Each area code node contains circuits that are provided to connect individual users to the network.

Abstract: Optical networks are increasingly employing optical network nodes having multiple interfaces to allow a node to direct optical signals received at any interface to any other interface connected to the node. Constructing a larger wavelength selective switching (WSS) module used in such a node can be complex and expensive. A method an apparatus for constructing a large WSS using parallelism is provided. In example embodiments, a larger WSS may include multiple parallel non-cascaded smaller WSSs and an optical coupler configured to optically couple the multiple parallel, non-cascaded smaller WSSs. This technique may be used to construct both N×1 and 1×N WSSs. Because the technique employs multiple parallel, non-cascaded WSSs, all inputs of a larger N×1 WSS and all outputs of a larger 1×N WSS are available receive or transmit external signals rather than being rather than being unavailable due to, for example, cascading smaller WSS devices together.

Abstract: An apparatus comprising a path computation element (PCE) configured for at least partial impairment aware routing and wavelength assignment (RWA) and to communicate with a path computation client (PCC) based on a PCE protocol (PCEP) that supports path routing, wavelength assignment (WA), and impairment validation (IV). Also disclosed is a network component comprising at least one processor configured to implement a method comprising establishing a PCEP session with a PCC, receiving path computation information comprising RWA information and constraints from the PCC, establishing impairment aware RWA (IA-RWA) based on the path computation information and a private impairment information for a vendor's equipment, and sending a path and an assigned wavelength based on the IA-RWA to the PCC. Disclosed is a method comprising establishing impairment aware routing and wavelength assignment for a plurality of network elements (NEs) in an optical network using routing and combined WA and IV.

Abstract: In accordance with some embodiments of the present disclosure, a method for spectrally spacing carrier waves comprises determining a frequency offset between a first frequency of a first optical carrier wave and a second frequency of a second optical carrier wave. The method further comprises adjusting the second frequency of the second optical carrier wave according to the frequency offset. The method additionally comprises combining a first optical signal associated with the first carrier wave and a second optical signal associated with he second carrier wave into a multi-frequency signal.

Abstract: A wavelength selective switch (WSS) based on an array of MEMS mirrors tiltable in 1-dimension about only one axis exhibits “hitting” or unwanted port connections during switching. Two WSS's can be cascaded to create M×N switching functionality in a hitless manner by the inclusion of block ports at specified positions in one or both of the WSS's. Greater use efficiency of ports can be achieved if quasi-hitless performance is acceptable.

Abstract: A transponder device that can form D&C paths with great versatility and high reliability without complicating a device configuration is provided, as well as an optical branching device and an optical signal transmission method. The transponder device that is independent of any directions of a wavelength switching function section at a node in a WDM transport network includes a D&C branching means that branches an optical signal input from the wavelength switching function section into one stream of dropped light and at least one stream of continued light.

Abstract: A network including nodes configured to provide auto-discovery and those that do not are provided in a network. The nodes that do not provide auto-discovery may be provided as end points or terminating nodes in the network. A path or circuit identifier is entered into a database at those nodes and communicated to a network management system. The network management system compares the path identifiers, and, if the two match, the network management system designates the nodes associated with the path identifiers as terminating nodes. A path through the network connecting these nodes can then be determined and monitored. In addition, fiber connection information may further be stored at each node and communicated to the network management system, such that links along the path can also be identified by the network management system. Thus, path determination and monitoring in a network including non-auto-discovering nodes can thus be obtained.

Abstract: A hybrid passive optical network (“PON”) includes a time-division multiplexing (“TDM”) optical line terminal (“OLT”) and a wavelength-division multiplexing (“WDM”) OLT. The TDM OLT communicates with a first group of customer premises (“CPs”) via TDM signals while the WDM OLT communicates with a second group of CPs via WDM signals. A remote node power splitter is coupled to receive the TDM and WDM signals and broadcast both the TDM signals and the WDM signals on all of its ports facing towards the CPs. Optical filters are disposed between the remote node power splitter and the second group of CPs. Each optical filter is configured to pass a sub-group of the WDM signals while blocking other WDM signals such that each of the second group of CPs receives its own allocation of WDM signals but does not receive WDM signals allocated to other CPs of the second group of CPs.

Abstract: Presented is a system and method for distributing a network application across a plurality of geographically dispersed network sites. The system comprises a plurality of network sites connected by a shared network and interconnected by a dedicated non-blocking communication network. The system can use different interconnecting network topologies based on the number of sites to be interconnected. The method balances the network application load and resources across the interconnected network sites based on a distribution policy implemented without burdening the shared network. The method provides redundancy capabilities by detecting the loss of a network site and redistributing the network application load to the remaining network sites.

Abstract: A network component comprising a generalized multiprotocol label switching (GMPLS) control plane controller configured to implement a method comprising transmitting a message to at least one adjacent control plane controller, wherein the message comprises a Type-Length-Value (TLV) indicating Routing and Wavelength Assignment (RWA) information, wherein the TLV comprises a Node Attribute TLV, a Link Set TLV, or both, and wherein the TLV further comprises at least one sub-TLV indicating additional RWA information. A method comprising communicating an open shortest path first (OSPF) link state advertisement (LSA) message comprising a TLV with at least one sub-TLV to a GMPLS control plane controller, wherein the TLV comprises a Node Attribute TLV, a Link Set TLV, or both, and wherein the TLV further comprises at least one sub-TLV indicating RWA information.

Abstract: An apparatus switches paths in a wavelength-multiplexing network in which a first number of wavelengths each used for a path to transmit an optical signal are multiplexed into an optical fiber. The apparatus includes an entire switching unit and a second number of individual switching units where the second number is smaller than the first number. The entire switching unit is configured to perform a path-switching process for switching a path, simultaneously on all the first number of wavelengths when failures have occurred for all the first number of wavelengths. The second number of individual switching units are each configured to perform the path-switching process individually on one of a third number of wavelengths included in the first number of wavelengths when at least one failure has occurred for the third number of wavelengths where the third numbers is smaller than the first number.

Abstract: The embodiments of the present invention describe a method for optimizing the capacity of an optical communication network that uses wavelength division multiplexing, wherein the spectral distribution of the signals intended to be transmitted over a plurality of channels is done dynamically through the use of a variable spectrum grid whose spectral spacings between two successive channels are determined based on the spectral width of said signals and in which dynamic filtering of said signals is carried out before their transmission in order to adjust their spectral width based on the available spectral space, and thereby reduce crosstalk between adjacent channels when the signals are transmitted.

Abstract: An optical network includes: an optical switch; a plurality of optical interface devices provided respectively for a plurality of servers and connected to the optical switch; and a manager to manage communication traffic of the plurality of servers. Each of the optical interface devices includes a fixed-wavelength optical transmitter and a wavelength tunable optical transmitter. A first optical path is set up via the optical switch by using the fixed-wavelength optical transmitters of the plurality of optical interface devices. The manager identifies first and second optical interface devices from among the plurality of optical interface devices in accordance with the communication traffic of the plurality of servers. A second optical path is set up between the first and second optical interface devices via the optical switch by using the wavelength tunable optical transmitters of the first and second optical interface devices.

Abstract: A device and a method are provided for merging a plurality of optical components associated with one wavelength into an optical component associated with the wavelength. The merging device includes, for each optical component of the plurality of components for merging: an optical element arranged to switch to a blocking position for blocking the optical component for merging, as a function of a blocking signal; a duplication element arranged to duplicate the optical component for merging for sending to combination element. The combination element is arranged to obtain the blocking signal by combining the duplicated optical components of the plurality of components other than the optical component for merging. A merging element is arranged to merge the optical components output by the optical element. The merging device may be integrated in an optical combiner of optical signals.

Abstract: Described herein are systems and methods of enhancing channel bandwidth in an optical system having a number of wavelength selective switching (WSS) devices. The method includes the steps of passing the optical signals through the WSS devices by: (i) spatially dispersing the wavelength channels of the optical signals; (ii) projecting the spatially dispersed channels onto corresponding predetermined regions of an optical manipulation matrix including a plurality of individually addressable manipulating elements; (iii) determining a modification function that specifies a state for each manipulating element within the predetermined region; and (iv) driving the elements of the corresponding regions at states specified by the function to selectively modify the channel band shape such that the received channel's bandwidth is substantially enhanced, and to spatially direct the wavelength channels to predetermined output ports of the WSS devices.

Abstract: A quantum communication system comprising a receiver and a plurality of transmitters, said receiver comprising a detector sub-system, each of said transmitters being configured to emit pulses of radiation, said detector subsystem comprising at least one detector, said detector being configured to detect said light pulses, the system comprising a timing control module, said timing control module being configured to control the number of light pulses received by the detector sub-system, such that just one light pulse from one transmitter reaches the detector sub-system at any one time, the timing control module also allowing the transmitter which sent said pulse to be identified.

Abstract: A grooming apparatus for an optical communication network is disclosed. The apparatus mainly includes a first photoelectric integration unit and an electrical-layer grooming unit. The first photoelectric integration unit includes a wavelength division multiplexing/demultiplexing unit and a photo-electric/electric-photo conversion unit. The wavelength division demultiplexing unit is configured to demultiplex a multi-wavelength optical signal into single-wavelength optical signals. The photo-electric conversion unit is configured to convert the single-wavelength optical signals to single-wavelength electrical signals. The electrical-layer grooming unit is configured to groom the single-wavelength electrical signals. The present invention overcomes the fatal defect of light dispersion, light power estimation, light power adjustment, OSNR limitation for a conventional OADM/ROADM system. Also, the flexibility of the electrical-layer grooming eliminates the wavelength broadcast and multicast issue.

Abstract: The present invention relates to a system and method for distributing digital signals over wavelength-switched optical transport networks with long-distance optical multicasting capability comprising a transmitter module and a receiver module in the headend of primary network and in the local node, respectively, for multicasting IPTV channels with HDTV, UHDTV and 3DTV signals. The transmitter module comprises an Ethernet switch, three DPSK modulators and a DWDM optical multiplexer. The receiver module comprises an Ethernet switch, three DPSK demodulators and a DWDM optical demultiplexer. In a novel manner, both modules combine 2 Gbps digital transmission, RZ-DPSK modulation and optical multicasting over a wavelength-switched optical network, WSON.

Abstract: Optical nodes in an optical network may provide directionless, colorless, contentionless, and gridless transmission, reception, and switching of optical signals in which a non-fixed number of optical channels and a non-fixed bandwidth for each optical channel is used. Optical nodes can use the full extent of the optical bandwidth due to the absence of channel spacing.

Abstract: In an optical access network system in which a relay station receives a wavelength multiplexed and time-division multiplexed optical signal (WDM optical signal) from an optical network, and the relay station transmits optical signals having specified wavelengths to subscriber units, the relay station demultiplexes the WDM optical signal into a plurality of groups with one group having a plurality of optical signals having a fixed wavelength interval between signals, then divides the optical signals of each group into k branches (k is the number of subscriber units) and inputs the signals to optical switches, and by turning ON/OFF the optical switches such that they are spaced in time, inputs the branched optical signals to the respective specified subscribers units.

Abstract: An OADM in a wavelength division multiplexing transmission system includes a wavelength selection switch that selects a predetermined wavelength from a multiple optical signal obtained by multiplexing a phase modulated signal and an intensity modulated signal and outputs the selected wavelength signal to a predetermined output port. The wavelength selection switch has a different delay for each wavelength of the multiple optical signal. For example, the wavelength selection switch includes a mirror array. Optical paths from the surfaces of mirrors arranged on the mirror array to the diffraction grating are different in the case of adjacent mirrors.

Abstract: An optical network is disclosed comprising one or more photonic switching nodes is disclosed. Each of the switching nodes comprises a plurality of input ports; at least one output port; and a switch configured to route messages between the plurality of input ports and the at least one output port and provide bufferless resolution of contention between messages for a common output port.

Abstract: A method for reallocating a wavelength in an optical wavelength multiplexer transmission system is disclosed. The method includes switching a supply of a first channel electric signal from a first optical transmitter device to a second optical transmitter device, the first optical transmitter device converting the first channel electric signal into an optical signal of a first wavelength, and the second optical transmitter device converting the first channel electric signal into an optical signal of a second wavelength differing from the first wavelength, and transmitting the optical signal of the second wavelength output from the second optical transmitter device.

Abstract: Optical superchannel methods and systems that couple two or more local oscillators into a single coherent receiver front end to receive multiple optical subcarriers are shown and described. With multiple local oscillators coupled into a single coherent receiver and appropriate optical selective filtering of the superchannel signal, non-neighboring subcarriers may be received by the single coherent optical receiver.

Abstract: Optical networks are increasingly employing optical network nodes having multiple interfaces to allow a node to direct optical signals received at any interface to any other interface connected to the node. Constructing a larger wavelength selective switching (WSS) module used in such a node can be complex and expensive. A method an apparatus for constructing a large WSS using parallelism is provided. In example embodiments, a larger WSS may include multiple parallel non-cascaded smaller WSSs and an optical coupler configured to optically couple the multiple parallel, non-cascaded smaller WSSs. This technique may be used to construct both N×1 and 1×N WSSs. Because the technique employs multiple parallel, non-cascaded WSSs, all inputs of a larger N×1 WSS and all outputs of a larger 1×N WSS are available receive or transmit external signals rather than being rather than being unavailable due to, for example, cascading smaller WSS devices together.

Abstract: A technique for transmitting an optical signal along an optical wavelength path through an optical network having a plurality of network nodes is disclosed. In one particular exemplary embodiment, the technique may be realized as a method for transmitting an optical signal along an optical wavelength path through an optical network having a plurality of network nodes. Such a method may comprise transmitting a first message from a first node to a second node requesting an optical wavelength path from the first node to at least the second node, and simultaneously configuring the first node for transmitting an optical signal along the optical wavelength path from the first node to the second node.

Abstract: The present disclosure provides high-degree reconfigurable optical add-drop multiplexing (ROADM) systems using bi-directional wavelength selective switches (WSSs) and optical circulators. A single WSS is utilized on each degree of a node in a bi-directional manner, i.e. both ingress and egress share the same WSS. Advantageously, the present invention eliminates conventional splitters/combiners thereby capping intra-node insertion loss to a certain value regardless of the number of degrees. More importantly, the present invention reduces noise penalty associated with high-degree nodes while minimizing cost.