Abstract: A packet switch/router including a first stage switch fabric receiving an electrical signal, a mid-stage buffer receiving and storing the electrical signal from the first stage switch fabric, and a second stage switch fabric receiving the electrical signal from the mid-stage buffer. Each switch fabric includes N layers of N×N arrayed waveguide gratings (AWGs), and each AWG has ingress ports and egress ports. A wavelength tunable device, such as a tunable laser, communicates with a source ingress port of an AWG and converts the received electrical signal to an optical signal having a wavelength selected for routing a packet from the source ingress port to a target egress port of the arrayed waveguide grating. A photoreceiver, such as a burst-mode photoreceiver, receives the propagated optical signal from the target egress port and converts the optical signal to the electrical signal.

Abstract: Embodiments of the present invention are directed to implementing high-radix switch topologies on relatively lower-radix physical networks. In one embodiment, the method comprises constructing the physical network (702) composed of one or more optical switches connected via one or more waveguides. A desired switch topology (704) is then designed for implementation on the physical network. The switch topology is then overlain on the switch network by configuring the optical switches and waveguides (706) to implement the switch topology on the physical network. The optical switches can be reconfigured following a transmission over the physical network and can be configured to implement circuit switching or packet switch.

Abstract: In one embodiment, a system for accelerating a packet stream includes a first accelerator configured to re-clock the packet stream from a first clock rate to a second clock rate to produce an accelerated packet stream, where the first clock rate is less than the second clock rate, where the packet stream has a first inter-packet gap, where the accelerated packet stream has a second inter-packet gap, and where the second inter-packet gap is greater than the first inter-packet gap. The system also includes a switch coupled to the first accelerator, where the switch is configured to switch the accelerated packet stream at the second clock rate to produce a switched packet stream.

Abstract: In one embodiment, a method for multi-wavelength encoding includes receiving an input optical packet stream having an address and data and encoding the address of the input optical packet stream producing an encoded address including a first group of symbols including a first selected symbol, where the first group of symbols has more than two symbols. The method also includes generating a first wavelength in accordance with the first selected symbol and generating an output optical packet stream having the data of the input optical packet and the first wavelength, where the first wavelength corresponds to the first selected symbol. Additionally, the method includes modulating the first wavelength with the input optical packet stream.

Abstract: A Wavelength Division Multiplexing (WDM) multi-mode switching system and method and method provides concurrent switching in various switching modes. For example, WDM links may communicate data 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 and core routers in the WDM multi-mode switching systems and methods provide switching and processing necessary to handle data provided in the various switching modes. Further, the WDM multi-mode switching systems and methods can also provide dynamic reconfiguration between the various switching modes.

Abstract: An optical packet switching system includes optical packet switching apparatus and an optical packet transmitting apparatus. The optical packet switching apparatus includes client optical delay units for delaying optical packet signals, network optical delay units for delaying one of the network optical packet signals, the network optical delay unit having a longer delay time than the client optical delay unit, an optical switch unit for switching the route of the inputted client optical packet signal so as to be sent out, an optical switch control unit for controlling the optical switch unit. The optical switch control unit is configured in such a manner as to detect a free time slot. The optical packet transmitting apparatus adjusts transmit timing, with which the client optical packet signal is sent out, in such a manner that the client optical packet signal is inserted into the free time slot.

Abstract: A method and a device are provided for swapping optical labels in an optical communication network. Optical information, including payload data and label data digitally encoded into the optical information, is received. At least one group of bits within the optical information is selectively inverted to rewrite the label data with new label data without changing the payload data. Each of the at least one group of inverted bits includes at least two bits and all bits of each of the at least one group of inverted bits are contiguous bits.

Abstract: A synchronous packet switch comprises output modules, input modules, optical connections and a switch control unit. The output modules comprise optical receivers each configured to receive optical signals at a different wavelength. The input modules receive electric signals carrying data cells to be routed. Each input module comprises optical transmitters, each configurable to generate an optical signal at a different wavelength, and routing apparatus comprising output ports. Each output module has at least one output port allocated to it. The routing apparatus is configurable to route a received optical signal to a selected output port. The optical connections are arranged to couple output ports to respective output modules. The switch control unit controls routing of the optical signals from the transmitters to the output modules and generates a routing control signal for configuring the routing apparatus to route an optical signal from a transmitter to a selected output port.

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: An optical packet switching apparatus includes an optical coupler for branching off a received optical packet signal, an optical switch unit for switching the route of one of the branched-off optical packet signals so as to be outputted, and an optical switch control unit for controlling the optical switch unit. The optical switch control unit includes an optical-to-electrical conversion unit for converting the other of the branched-off optical packet signals into an electrical packet signal, a serial/parallel conversion unit capacitively coupled to the optical-to-electrical conversion unit, a packet density detector for detecting the packet density of the received packet signal, and a DC offset adjustment unit for adjusting the DC offset voltage of the packet signal, inputted to the serial/parallel conversion unit, according to the packet density information detected by the packet density detector.

Abstract: A data transmission method, a data transmission system and a data processing node are provided to improve the resource utilization. The data transmission method includes the following steps: a second data processing node receives control information sent from a first data processing node through a preset control channel, where the control information includes at least bandwidth information of a data channel for sending optical burst data and corresponds to the service information of optical burst data of the first data processing node; the second data processing node controls the transmission of pending optical burst data according to the bandwidth information. A data processing node and a data transmission system are also provided.

Abstract: An optical packet switching system includes: an optical packet transmitter device configured to transmit an optical packet signal; and an optical packet switching device configured to route and output an input optical packet signal. The optical packet transmitter device is configured to adjust gap time between optical packets transmitted. The optical packet transmitter device adjusts the gap time to a fixed value defined by time required for switching in the optical packet switching device.

Abstract: An optical packet switching apparatus includes an optical switch unit for switching the route of a received optical packet signal and output the received optical packet signal, and an optical switch control unit for extracting destination information from the received optical packet and generating a control signal for the optical switch unit according to the destination information. The optical switch control unit includes a clock generator for generating a plurality of local clocks of different phases, and a clock selector for selecting a local clock having the smallest phase difference with the received optical packet from the plurality of local clocks. The optical switch control unit generates the control signal using the local clock selected by the clock selector as an operation clock.

Abstract: A multi-chassis network device includes a plurality of nodes that operate as a single device within the network and a switch fabric that forwards data plane packets between the plurality of nodes. The switch fabric includes a set of multiplexed optical interconnects coupling the nodes. For example, a multi-chassis router includes a plurality of routing nodes that operate as a single router within a network and a switch fabric that forwards packets between the plurality of routing nodes. The switch fabric includes at least one multiplexed optical interconnect coupling the routing nodes. The nodes of the multi-chassis router may direct portions of the optical signal over the multiplexed optical interconnect to different each other using wave-division multiplexing.

Abstract: A network component comprising at least one processor configured to implement a method comprising transmitting a request to compute a routing assignment, a wavelength assignment, or both, wherein the request comprises a lightpath constraint indicator is disclosed. Also disclosed is an apparatus comprising a Path Computation Client (PCC) configured to transmit a request to and receive a reply from a Path Computation Element (PCE), wherein the request comprises a lightpath constraint, and wherein the reply comprises a routing assignment, a wavelength assignment, an error message, a no-path indication, or combinations thereof. Included is a method comprising receiving a request comprising a request parameter (RP) object comprising a lightpath constraint, sending a reply comprising a routing assignment, a wavelength assignment, an error message, a no-path indicator, or combinations thereof, wherein the request is received and the reply is sent using path computation element protocol (PCEP).

Abstract: In the field of communications, a method and a system for packet transmission in an optical communication system, and an Optical Line Terminal (OLT) are provided. The method includes: receiving, from a port, a first uplink packet from an Optical Network Unit (ONU), where the first uplink packet includes a Logical Link Identifier (ID); determining a first ID corresponding to the first uplink packet, where the first ID includes an ONU ID or a Port ID; acquiring a Multiprotocol Label Switching (MPLS) tunnel label according to the Logical Link ID and the first ID; and transmitting a second uplink packet on an MPLS tunnel corresponding to the MPLS tunnel label, where the second uplink packet includes data in the first uplink packet and the MPLS tunnel label. The system includes an ONU and an OLT.

Abstract: A photonic-based distributed network switch and method where the switch is designed to reduce or filter optical data frames entering a port of the switch so that only data frames that are appropriate for the port are forwarded from the port. This reduces the amount of data that needs to be handled by the port interface, which is especially important where the port may be using legacy interface technology that may be incapable of handling the volume of data entering the port.

Abstract: The invention provides a control layer for an Optical Burst Switch (OBS) system, said system comprising at least one stage configured with a closed optical burst switch addressing scheme and one or more ports for sending or receiving data packets. The control layer comprises a control addressing scheme independent of the closed optical addressing scheme and means to provide interconnectivity for each port with every other port. In one embodiment there is provided a closed optical burst switch ring network. The control layer encapsulates or maps the optical data at a port into an independent packet format and passes the independent packet format into a queuing system for transmission by the optical burst switch ring network to a destination port.

Abstract: Methods and systems for optical signal grooming that include providing one or more input signals, each having one or more modulated subcarriers, to a grooming processor; and grooming the input signals at a subcarrier level with the grooming processor to produce one or more output signals by arranging the modulated subcarriers in the output signals according to a grooming operation such that the modulated subcarriers are not demodulated or decoded prior to grooming.

Abstract: The present disclosure provides virtual router/switch systems and methods with a domain of optical switches operating as a single, virtualized router using a control plane design combining centralized control of higher layer packet switching functions with distributed control over transport switching functions. The virtual router systems and methods simplify and reduce cost of Internet Protocol (IP) networks by removing the core routers, replacing them with lower cost, high capacity optical switches which are Packet Optical Transport Systems (POTS). The virtual router systems and methods avoids full mesh connectivity of the edge routers and the associated need to maintain routing adjacencies to each of the other edge routers. The virtual router systems and methods include a centralized IP layer management. Further, the virtual router systems and methods include distributed control of the optical layers.

Abstract: A network includes a plurality of interconnected nodes utilizing an all-broadcast architecture for a plurality of wavelengths therebetween; a routing protocol configured to compute a loop-free path through the plurality of interconnected nodes, wherein the loop-free path is computed for at least one wavelength of the plurality of wavelengths using routing constructs adapted to a photonic domain; and at least one blocking element configured to selectively block the at least one wavelength based on the computed loop-free path. A routing method photonic node are also disclosed.

Abstract: Methods and apparatus to deploy fiber optic based access networks are disclosed. An example access network comprises a first fiber optic cable segment to couple an optical access head-end to a first pedestal and to transport user data, a second fiber optic cable segment to couple the first pedestal to a second pedestal and to transport a first portion of the user data to the second pedestal, a drop cable segment to couple the first pedestal to a customer premises and to transport a second portion of the user data to the customer premises, and a switch at the first pedestal to route the first portion of the user data between the first and second fiber optic cable segments and to route the second portion of the user data between the first fiber optic cable segment and the drop cable segment.

Abstract: A label switching method is provided. When a Passive Optical Network (PON)-based Label Switching Path (LSP) is established, a PON logical service transmission channel is established between an Optical Line Terminal (OLT) and an Optical Network Unit (ONU). According to an identifier (ID) of the PON logical service transmission channel as a PON label, a PON-based Forwarding Information Base (FIB) table on the ONU is updated, and a PON-based Label Forwarding Information Base (LFIB) table on the OLT is updated, where the PON-based LFIB table records a forwarding relationship between an ingress port plus an ingress label and an egress port plus an egress label, and the PON-based FIB table records a forwarding relationship between the ingress port plus a destination address and the egress port plus the egress label. Therefore, the problems between network segments of different forwarding characteristics, protocol variation, inter-segment conversion, and mapping and control complexity are avoided.

Abstract: New designs of optical devices, particularly for dropping a selected wavelength or a group of wavelengths as well as demultiplexing a multiplexed signal into several signals, are disclosed. An optical device employs thin film filters with reflectors to reassemble as a fiber Bragg grating. Depending on implementation, a reflector may be a mirror or a coated substrate disposed in a unique way to reflect a light beam from a filter back to a common port of a device. The reflector may also be coated accordingly to bypass a certain portion of the light beam for other purposes. As a result, the optical devices so designed in accordance with the present invention are amenable to small footprint, enhanced impact performance, lower cost, and easier manufacturing process.

Abstract: A frequency assignment method for selecting a frequency width used on a route connecting between a start point and an end point when the start point and the end point of an optical signal are supplied in a photonic network including an optical node that includes an optical switch for switching the optical signal without electrically terminating the optical signal is disclosed. The frequency assignment method includes steps of: obtaining a correlation amount of use state of wavelength or frequency between adjacent links by referring to a route calculation result; determining a fixed frequency width or variable frequency width to be set for a communication route based on the correlation amount; and assigning the fixed frequency width or the variable frequency width on the route.

Abstract: The present disclosure discloses data vortex architecture with bidirectional links in which the packets are routed both in forward as well as in reverse directions through a single node. The disclosed arrangement avoids any packet congestion in the network and improves the BER characteristics.

Abstract: A photonic network includes a plurality of nodes each supporting add and drop of at least Y wavelengths, a plurality of optical links interconnecting the plurality of nodes, the plurality of optical links support up to X wavelengths and Y?X, an optical routing protocol configured to compute a loop-free path through the plurality of nodes on the plurality of links, the loop-free path is computed for one of the X wavelengths or a group of the X wavelengths using routing constructs adapted to a photonic domain, and optical components at each of the plurality of nodes configured to selectively block at least one of the X wavelengths based on the computed loop-free path. A photonic routing method and photonic node are also disclosed.

Abstract: A path computation method includes defining photonic constraints associated with a network, wherein the photonic constraints include wavelength capability constraints at each node in the network, wavelength availability constraints at each node in the network, and nodal connectivity constraints of each node in the network, and performing a constrained path computation in the network using Dijkstra's algorithm on a graph model of the network with the photonic constraints considered therein. An optical network includes a plurality of interconnected nodes each including wavelength capability constraints, wavelength availability constraints, and nodal connectivity constraints, and a path computation element associated with the plurality of interconnected photonic nodes, wherein the path computation element is configured to perform a constrained path computation through the plurality of interconnected nodes using Dijkstra's algorithm on a graph model with the photonic constraints considered therein.

Abstract: Each of a plurality of data flows is classified as having a respective data flow type, and each data flow is assigned to one of a plurality of subcarrier groups, based on the data flow's type, wherein each subcarrier group comprises a respective plurality of subcarriers. First data flows assigned to a first subcarrier group are transmitted exclusively on respective subcarriers in the first subcarrier group, and second data flows assigned to a second subcarrier group are transmitted together on all of the subcarriers in the second subcarrier group.

Abstract: In one aspect, a system includes one or more electrical switches to transfer data in a data network; one or more optical switching groups coupled to each electrical switch, each switching group having one or more server racks, each server rack coupled to a top of rack (TOR) switch and an optical transceiver coupled to the TOR switch; and an optical switching unit (OSU) coupled to the one or more optical switching groups.

Abstract: A photonic-based distributed network switch that utilizes multiple photonic broadcast stars and separate optical transmitters to improve overall reliability, allow load balancing, and provide failover for the network switch and the network with which the switch is used.

Abstract: Disclosed are, inter alia, methods, apparatus, computer-storage media, mechanisms, and means associated with the coordinated updating of forwarding information bases (FIBs) in a multistage packet switching device, which performs at least lookup operations on multiple different FIBs in determining how to forward a packet. One embodiment uses lookup operations on two different FIBs, with these being an ingress FIB on an ingress line card and an egress FIB on an egress line card. In response to a change in the forwarding information for a stream of packets, the egress FIBs are first updated to include both the old and new forwarding information. After all egress FIBs have been updated, the ingress FIBs are updated to use the new forwarding information. This update procedure is designed to eliminate loss or duplication of packets induced during the updating of these FIBs to use the new forwarding information.

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: Techniques are provided to automatically configure packet based network services over Dense Wavelength Division Multiplex (DWDM) network communication links. An optical wavelength is detected at an optical interface of a network device configured to send traffic between a packet switched network and an optical network. A message is sent to an optical control plane comprising information configured to request optical configuration information for the optical wavelength. A response to the message is received comprising the optical configuration information and the wavelength is activated at the optical interface using the optical configuration information. A frame is received over the wavelength that is formatted according to an optical protocol. Packet switched network information is extracting from an overhead portion of the frame that is configured to identify network parameters for configuring a packet switched network link and the associated routing.

Abstract: A multi-chassis network device includes a plurality of nodes that operate as a single device within the network and a switch fabric that forwards data plane packets between the plurality of nodes. The switch fabric includes a set of multiplexed optical interconnects coupling the nodes. For example, a multi-chassis router includes a plurality of routing nodes that operate as a single router within a network and a switch fabric that forwards packets between the plurality of routing nodes. The switch fabric includes at least one multiplexed optical interconnect coupling the routing nodes. The nodes of the multi-chassis router may direct portions of the optical signal over the multiplexed optical interconnect to different each other using wave-division multiplexing.

Abstract: An optical input/output (I/O) bus system for connecting a plurality of external devices with a central processing unit (CPU) or memory in a specific system using an optical signal is provided.

Abstract: A system for optical data communication, including: a first sending node including a first data item for transmission to a first receiving node during a first timeslot; a second sending node including a second data item for transmission during a second timeslot; a first optical data link (ODL) and a second ODL; a first output switch configured to switch the first data item from the first sending node onto the first ODL during the first timeslot; a second output switch configured to switch the second data item from the second sending node onto the first ODL during the second timeslot; an optical coupler connecting the first and second ODL; and a first input switch operatively connecting the first receiving node with the second ODL and configured to switch the first data item from the second ODL to the first receiving node during the first timeslot.

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: A method is provided for routing optical data, which method comprises transmitting optical addressing data to a first network element having routing capabilities, assigning an appropriate optical link connecting the first network element with a second network element where the assignment is based on the optical addressing data, and transmitting the optical data via the assigned optical link.

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 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 and delay system for optical encryption and/or optical decryption may comprise a switch bank, a set of optical delay lines, a combiner, and a processor. The switch bank may be configured to receive an optical signal in a first arrangement and route the optical signal to the set of optical delay lines according to a switching arrangement key. The set of optical delay lines may be configured to provide delays to the optical signal. The combiner may be configured to receive the optical signal with delays from the set of optical delay lines and combine the optical signal into a second arrangement. The processor may be configured to receive the switching arrangement key and control the switch bank according to the switching arrangement key. The switching arrangement key may comprise a set of instructions for routing the optical signal.

Abstract: A packet-optical integrated switch without an optical transponder, includes: a packet line card configured to output an Ethernet packet signal to a pre-set output port; a packet switch fabric configured to transfer the packet signal from the packet line card to the output port previously set in a destination address included in the packet signal; a 10 gigabit Ethernet (10 GbE)/optical transport unit level 2 (OTU2) integrated line card configured to convert the packet signal from the packet switch fabric into an OTU2 optical signal having a pre-set wavelength; and a wavelength selection switch fabric configured to allocate the optical signal from the 10 GbE/OTU2 integrated line card to a pre-set wavelength division multiplexing (WDM) port by pre-set wavelength to exchange the optical signal to each port by wavelength, wherein the packet line card, the packet switch fabric, the 10 GbE/OTU2 integrated line card, and the wavelength selection switch fabric perform the reverse operations of the process, respectivel

Abstract: Data center network architectures, systems, and methods that can reduce the cost and complexity of data center networks. Such data center network architectures, systems, and methods employ physical optical ring network and multi-dimensional network topologies and optical nodes to efficiently allocate bandwidth within the data center networks, while reducing the physical interconnectivity requirements of the data center networks. The respective optical nodes can be configured to provide various switching topologies, including, but not limited to, chordal ring switching topologies and multi-dimensional chordal ring switching topologies.

Abstract: An apparatus has a plurality of transmitters for transmitting optical packet signals having wavelengths; a multiplexer for multiplexing the optical packet signals transmitted by the plurality of transmitters; a packet scheduler controlling a timing at which each of the transmitters transmits the optical packet signal; and an assister for controlling power of assist light in accordance with a signal from the packet scheduler and causing the assist light to be wavelength-multiplexed with the wavelength multiplexed light such that a total sum of power of the wavelength multiplexed light and the power of the assist light is held constant under a predetermined condition.

Abstract: The present invention is to provide an optical access network in which a remote unit receives an optical burst signal. A central unit (OLT) transmits a DC-balanced optical continuous signal including packets having identification information for identifying each remote unit (ONU) to an optical switching module (OSM). The optical switching module (OSM) receives the DC-balanced optical continuous signal from the central unit (OLT), optically switches the packets based on the identification information, and transmits a DC-balanced optical burst signal including the packets to the remote unit (ONU). The remote unit (ONU) receives the DC-balanced optical burst signal and acquires the packets transmitted to the remote unit (ONU).

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: An optical packet signal transmission device includes a transmitting unit which includes a plurality of data delay circuits; a plurality of optical branch units which branches some of the optical packet signals as monitor lights; an optical switch which selects one of the monitor lights; a test signal generation circuit which generates a test signal which is used to adjust a delay amount in the data delay circuits; a reference optical pulse generation circuit which generates a reference optical pulse based on the test signal; an optical phase comparator which detects an relative optical phase difference by comparing the phases of the selected monitor light and the reference optical pulse; and a control circuit which sequentially sends the test signals to the data delay circuits, switches the selected monitor light, detects a relative optical phase, determines the delay amount based on a detection result, and sets the delay amount.

Abstract: A packet switch architecture that can switch optical packets at high throughputs without using any random access memory, without fragmenting variable length packets into fixed length fragments and reassembling them, and without converting the optical packets into electronic packets. Programmable delay lines are use which delay the output of each packet for a programmable amount which may be re-programmed while the packet is being delayed by the programmable delay line. Programmable delay line controllers manages the delays imposed by the programmable delay lines so as to have a look-ahead phase during which information about the packets is gathered and a shift phase during which the sequence of packets is shifted to match an output sequence.

Abstract: A packet-switched WDMA ring network has an architecture utilizing packet stacking and unstacking for enabling nodes to access the entire link capacity by transmitting and receiving packets on available wavelengths. Packets are added and dropped from the ring by optical switches. A flexible credit-based MAC protocol along with an admission algorithm enhance the network throughput capacity.