Abstract: A computer system and method for transmitting LAN signals over transport systems. LAN signals are generated in any client LAN compliant interface. A transceiver receives the client LAN signal in the LAN format. The client LAN signals are not converted to a SONET transmission format at any time before reaching the transceiver. The transceiver then converts the client LAN signal to an internal electrical LAN signal before re-clocking the internal electrical LAN signal. The re-clocked internal electrical LAN signal is then re-modulated into a second LAN signal. The second LAN signal is then transmitted to a transport system.

Abstract: A method for establishing an end-to-end service is provided in the present invention, which includes: acquiring link information in a network and multi-stage multiplexing capability constraint information supported by gateway network elements; when an end-to-end path computation request is received, according to the link information and the multi-stage multiplexing capability constraint information, performing an end-to-end routing computation to acquire an end-to-end routing, and selecting a multi-stage multiplexing capability used on a gateway network element passed by the end-to-end routing; and configuring the end-to-end service, and configuring the selected multi-stage multiplexing capability on the gateway network element passed by the end-to-end routing. A system for establishing the end-to-end service, an optical transport network and a signal transmission method thereof are also provided in the present invention, which can all implement the interconnection between new networks and old networks.

Abstract: Disclosed herein are optical distribution networks and corresponding methods for providing physical-layer redundancy. Example embodiments include a head-end passive optical splitter-combiner (OSC) to split optical signals from an Optical Line Terminal (OLT) onto primary and secondary optical paths for redundant distribution to optical network terminal(s) (ONTs), a passive access OSC for tapping the redundant signals, and an optical switch for selecting between the redundant signals and providing an ONT access to the selected signal. Example optical distribution networks and corresponding methods provide multiple drop points, a fully cyclical path, and autonomous protection switching, all at low cost. A further advantage of these networks and methods is that where faults may occur, maintenance may not be required for a certain time.

Abstract: A data transmission system (200) comprises: a main optical packet ring (201) comprising a plurality of separate packet transmission channels; and a plurality of secondary optical packet rings (202) interconnected through the main optical packet ring. Each of the secondary optical packet rings (202) comprises a plurality of nodes (400). Each of said packet transmission channels of the main optical packet ring (201) is connected to a different node of each secondary optical packet ring (202), respectively.

Abstract: A node device in an optical transport ring network including plural node devices connected in a ring form using plural optical transmission paths so that optical transport frames of a working line and a protection line are transmitted using the plural optical transmission paths, includes a control information transmitter, when a failure occurs in the optical transmission paths, transmitting the optical transport frame to an opposing node device as a transmission destination node in the optical transmission paths, the optical transport frame including switching control information; and a switcher receiving the optical transport frame including switching control information, the optical transport frame being transmitted to the node device as the transmission destination node, forming a loop back to fold a transmission path between the plural optical transmission paths, and switching the optical transmission path from the work line to the protection line.

Abstract: An optical network interconnect device interconnects a first WDM network for transmitting a WDM optical signal with first wavelength spacing and a second WDM network for transmitting a WDM optical signal with second wavelength spacing that is wider than the first wavelength spacing. The optical network interconnect device includes a filter to remove a wavelength component which is not used in the second WDM network from an WDM optical signal transferred from the first WDM network to the second WDM network.

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: An electronic circuit device, including a combined optical transmission and cooling fluid conduit network. The network includes at least one cooling conduit having an optical transmission medium. The network is configured to convey a cooling fluid via the at least one cooling conduit and to convey an electromagnetic signal via the optical transmission medium. The network is in thermal communication with a first set of one or more components of the electronic circuit device and in signal communication with a second set of one or more components of the electronic circuit device. The first set and second set of components are at least partly overlapping. A method for conveying optical signal in such an electronic circuit device is also provided.

Abstract: A node (260, 50) for a multi-token optical communications network has optical channels between the node and other nodes, each channel having a token (T1, T2, T3), passed between nodes, to indicate that a corresponding optical channel is available for transmission during a token holding time. The node has a transmitter (280) for transmitting packets over the optical channels, a buffer (170, 270) for queuing packets before transmission, and a transmit controller (170, 290) configured to control the buffer to forward an initial packet or packets from the buffer to the transmitter once a token has been received. The transmit controller determines how much of the token holding time remains after the transmission of the initial packet or packets, and then controls the buffer to forward a further packet according to the remaining token holding time. A maximum packet delay can be reduced where there is asymmetric traffic. A token holding time can be different for different nodes.

Abstract: The invention relates to a remote node architecture for a fiber-optic network, especially for low bit-rate data transmission, the fiber-optic network comprising a central node and a plurality of remote nodes serially connected to each other or to the central node, respectively, the central node and the remote node being capable of communicating by means of digital optical signals created by the central node or a respective remote node, each digital optical signal comprising a data frame.

Abstract: Communications method between a main station and processing nodes includes interconnecting the main station and the nodes in an optical path defining adjacent nodes and non-adjacent nodes, operatively grouping the nodes in a plurality of distinct sub-groups, each formed by non-adjacent nodes, at least one of said sub-groups including at least two nodes generating at the main station a multiplexed optical signal propagating along the path for serving the nodes, the multiplexed optical signal including a plurality of optical channel signals having a respective plurality of distinct carrier wavelengths, each carrier wavelength being associated with a respective sub-group of nodes, and serving each node of each sub-group of nodes with a respective portion of the optical channel signal having the associated carrier wavelength.

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 topologies, optical nodes, and optical junction nodes to efficiently allocate bandwidth within the data center networks, while reducing the overall physical interconnectivity requirements of the data center networks.

Abstract: Methods and apparatus for line coding in a communications network are described. According to one embodiment of the invention, downstream communications traffic bits are received and mapped into downstream bit positions of a transmission structure. A pre-selected bit in each upstream bit positions of the transmission structure is provided to form a downstream transmission structure. A downstream optical signal carrying the downstream transmission structure is generated for transmission. Upstream communications traffic bits are also received and mapped into the upstream bit positions of the transmission structure to form an upstream transmission structure. An upstream optical signal carrying the upstream transmission structure is generated for transmission.

Abstract: A hub node in a wavelength division multiplexed optical network automatically discovers at least one of new client-side optical ports and new edge-side optical ports. The hub node comprises a wavelength switch network, port discovery equipment, and a controller. The wavelength switch network routes any wavelength channel that does not support a matching pair of client-side and edge-side ports to port discovery equipment at the hub node. The port discovery equipment searches for new ports, and, responsive to finding a new port, automatically discovers a predefined set of one or more attributes of the new port. The controller determines that a client-side port and an edge-side port are a matching pair of ports if discovered sets of attributes of those ports match according to one or more predefined rules. The controller then controls the wavelength switch network to re-route the wavelength channel supporting that matching pair between those ports.

Abstract: An optical transmission system comprises a metropolitan core network operated in a wavelength division multiplexing mode and connected via metro connection devices to access connections to optical network terminals connected by means of a passive optical splitter. The metro connection devices contain regenerators and wavelength converters, so that data regeneration takes place between the network terminals and the central management and switching unit. This makes it possible to cover distances around 100 km.

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: A remote node architecture for a fiber-optic network, especially for low bit-rate data transmission, the fiber-optic network architecture comprises a central node and a plurality of remote nodes serially connected to each other or to the central node, respectively. The central node and the remote nodes are capable of communicating by means of digital optical signals created by the central node or a respective remote node, each digital optical signal comprising a data frame. The remote node comprises an optical connection network, a single transceiver device comprising an optical receiver unit and an optical transmitter unit, and an electronic controller device for controlling the transceiver device. The optical connection network defines a western optical connection port, an eastern optical connection port, an internal optical receiving port being connected to the optical receiver unit and an internal optical transmitting port being connected to the optical transmitter unit.

Abstract: A ring network system includes a plurality of node apparatuses that are sequentially connected through a transmission medium that is formed in a ring form. In the ring network system, the remaining node apparatuses, except for a first node apparatus of the plurality of node apparatuses pass an optical signal that is transmitted from the first node apparatus, and a second node apparatus corresponding to a destination of the optical signal among the remaining node apparatuses, extracts the optical signal while transferring the first optical signal to a next node apparatus of the second node apparatus.

Abstract: Various embodiments of the present invention are directed to optical broadcast buses configured with shared optical interfaces for fan-in and fan-out of optical signals. In one aspect, an optical broadcast bus comprises a number of optical interfaces, a fan-in bus optically coupled to the number of optical interfaces, and a fan-out bus optically coupled to the number of optical interfaces. Each optical interface is configured to convert an electrical signal produced by the at least one node into an optical signal that is received and directed by the fan-in bus to the fan-out bus and broadcast by the fan-out bus to the number of optical interfaces. Each optical interface also converts the optical signal into an electrical signal that is sent to the electronically coupled at least one node for processing.

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: A computer system and method for transmitting LAN signals over transport systems. LAN signals are generated in any client LAN compliant interface. A transceiver receives the client LAN signal in the LAN format. The client LAN signals are not converted to a SONET transmission format at any time before reaching the transceiver. The transceiver then converts the client LAN signal to an internal electrical LAN signal before re-clocking the internal electrical LAN signal. The re-clocked internal electrical LAN signal is then re-modulated into a second LAN signal. The second LAN signal is then transmitted to a transport system.

Abstract: In accordance with embodiments of the present disclosure, a method for demand aggregation is provided. The method may include routing demands in a ring network such that a length for each routed demand does not exceed a route length maximum, and a load imbalance at each node in the ring network is minimized. The method may also include maximizing optical line card sharing by assigning routed demands sharing common ends to the same wavelength.

Abstract: An optical ring network has one or more working wavelengths and multiple protection wavelengths adapted to support the working wavelength(s). Routing tables may be used in network nodes to assign traffic of a failed working wavelength to a protection wavelength. The protection technique may be applied to networks employing, for example, Dense Wave Division Multiplexing (DWDM).

Abstract: A device receives Long Term Evolution (LTE) architecture information, Internet protocol (IP) network architecture information, and transport network information, and determines traffic patterns of a LTE network based on the LTE architecture information. The device also generates proposed LTE metropolitan optical transport networks (OTNs) based on the determined traffic patterns and one or more of the LTE architecture information, the IP network architecture information, and the transport network information. The device further determines transit switching for the proposed LTE metropolitan OTNs, and selects, from the proposed LTE metropolitan OTNs, a metropolitan OTN optimized for the LTE network.

Abstract: The invention provides an optical burst switch in an Optical Burst Switched (OBS) communication network, said optical burst switch comprising means for monitoring and maintaining mesh of virtual optical paths from a communication node to a plurality of other communication nodes, arranged in a ring network, enabling traffic data to be transmitted and/or received between nodes via a physical optical path. The switch also provides means for sending a data packet probe on a virtual path from a node to each other node in the OBS communication network, wherein data packet probe information received at said switch provides information of availability of the physical optical path for sending traffic data between nodes. The switch can be configured such that the rate at which this path monitoring is scheduled guaranteeing less than 50 ms protection switch in the event of monitoring a failed or degraded path.

Abstract: An optical ring network for fixed length messages from a plurality of nodes for transmission to different nodes uses a plurality of wavelengths for transmission, and messages for transmission are ordered and arranged on a per-wavelength basis to minimize a transmit finish time. Each node may be operated in an ADM (add drop multiplexer) mode where an optical node removes information on a particular wavelength and adds information on the same particular wavelength, or each node may be operated in a CDC (colorless, directionless, contentionless) mode where information is assigned to a wavelength according to a selection algorithm which may place it on any wavelength without regard to an original node wavelength. The selection algorithm optimizes selection of messages and wavelengths for transmit finish time.

Abstract: Delivering multicast data traffic over a communication network includes a first network node delivering multicast data traffic to second network nodes. The first and second network nodes are connected by a transmission network in a ring architecture and implement a point-to-multipoint layer 2 protocol. A method includes at the first network node: collecting alarms signals indicative of a failure along the whole ring and of the second network nodes. Based on a current state of the alarm signals, delivering the multicast data traffic either in a first delivery direction along the ring, or in a second delivery direction along the ring opposite to the first delivery direction, or in both the first and second delivery directions. At each of the second network nodes: collecting alarm signals indicative of a failure of the transmission network locally to the second network node and of the second network node.

Abstract: A system and method for a transparent WDM metro ring architecture in which optics enables simultaneous provisioning of dedicated wavelengths for high-end user terminals, while low-end user terminals share wavelengths on “virtual rings”. All wavelengths are sourced by the network and remotely modulated at customer “End Stations” by low cost semiconductor optical amplifiers, which also serve as transmission amplifiers. The transparent WDM metro ring architecture permits the communication of information and comprises a fiber optical feeder ring, at least one fiber optical distribution ring, a network node (NN), at least one access node (AN) said network node and said at least one access node connected via said fiber optical feeder ring and at least one end station (ES) connected via said fiber optical distribution ring to said at least one access node, wherein said user is attached to said at least one end station.

Abstract: Optical networks occasionally experience a fault along a communications path. Service providers prefer to have an alternative communications path available to enable users to still communicate in a seamless manner. Accordingly, a method and corresponding apparatus for providing path protection for dedicated paths in an optical network is provided.

Abstract: An apparatus comprising a dispersive fiber optical loop for delaying a first and second sideband, relative to each other, of a light modulated by a radio frequency signal to create a pair of pulses, a coupler for tapping a replica of the pair of pulses from the loop; and an auto-correlation module, coupled to the coupler, for correlating the replica of the pair of pulses with each other.

Abstract: An optical network includes a first optical network for carrying a plurality of optical channels in an optical fiber, wherein each of the plurality of optical channels comprise a discrete wavelength in a first range of wavelengths. A second optical network coupled to the first optical network by a first tunable filter. A first customer location coupled to the second optical network by a second tunable filter. The first tunable filter is configured to pass a first set of optical channels from the first optical network to the second optical network. The first set of optical channels includes a subset of the plurality optical channels within a second range of wavelengths less than the first range of wavelengths. The second tunable filter is configured to pass a particular channel within the first set of optical channels from the second optical network to the first customer location.

Abstract: A method of closed loop control for an optical link is presented, utilizing a copper feedback connection between the optical transmitter and optical receiver, suitable for short distance applications. An architecture is provides that may be used to define and maintain an optimum optical launch power for a defined bit error rate, guaranteeing extinction ratio and absolute optimum operating power. The invention also includes the use of such a loop in achieving fast link initialization and dynamic optimization to compensate for all effects of time and temperature for all components within the link.

Abstract: A network setup method used in a ring network including a plurality of transmission equipments. The method includes: transmitting a frame in the ring network; causing each of the transmission equipments to write an identifier to the frame according to a specified rule; determining whether or not a plurality of identifiers written to the frame by the plurality of transmission equipments satisfy a specified condition; and causing each of the transmission equipments to obtain a corresponding identifier according to the specified rule from among the plurality of identifiers, when the plurality of identifiers satisfy the specified condition.

Abstract: A network device establishes first and second Ethernet link aggregation groups (LAGs) at a first access site of an optical transport network (OTN), and creates a first optical channel (OCh) LAG subpath from the first Ethernet LAG, via a second access site of the OTN, to an Ethernet LAG at a third access site of the OTN. The network device also creates a second OCh LAG subpath from the first Ethernet LAG, via a distribution site of the OTN, to the Ethernet LAG at the third access site, and creates a first optical data unit (ODUk) LAG subpath from the second Ethernet LAG to an Ethernet LAG at the second access site. The network device further creates a second ODUk LAG subpath from the second Ethernet LAG, via the distribution site and the third access site, to the Ethernet LAG at the second access site.

Abstract: Disclosed are a wavelength multi-casting method and device in a multi-ring network, and more particularly, a wavelength multi-casting method and device in a multi-ring network capable of configuring an economical network. The wavelength multi-casting method in the multi-ring network according to the exemplary embodiment of the present invention includes: receiving, by one node, optical signals from other nodes within a ring network to which the node belongs; and multi-casting, by the node, an optical wavelength to neighboring nodes by a scheme of dropping and continuing the transmitted optical signals.

Abstract: The invention provides a burst transmission optical fiber wavelength routed ring network and method comprising a plurality of nodes on a network ring where each node can drop and add a wavelength. The network has a control means to control the wavelength to be transmitted on the network ring in a burst transmit mode from each node over a scheduling interval. The invention provides a random generator for generating a plurality of gap intervals over the scheduling interval, such that the gap intervals allow for wavelengths from different nodes to transmit wavelengths in said gaps to achieve a fair access to bandwidth and fair latency in the ring network.

Abstract: A radial optical data interchange packaging comprises a central core; a plurality of central core photo transceivers emerging from an exterior side surface of the central core; a mother board coupled to the central core, wherein the mother board is perpendicularly oriented below and abutting the central core; a plurality of retention slots on the mother board, wherein the retention slots radially extend away from the central core; and a plurality of cards held by the retention slots, wherein each of the plurality of cards comprises a set of card photo transceivers that optically communicate with the central core photo transceivers.

Abstract: Data center network architectures that can reduce the cost and complexity of data center networks. The data center network architectures can employ optical 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 data center network architectures also allow computing resources within data center networks to be controlled and provisioned based at least in part on a combined network topology and application component topology, thereby enhancing overall application program performance.

Abstract: An optical ring network has one or more working wavelengths and multiple protection wavelengths adapted to support the working wavelength(s). Routing tables may be used in network nodes to assign traffic of a failed working wavelength to a protection wavelength. The protection technique may be applied to networks employing, for example, Dense Wave Division Multiplexing (DWDM).

Abstract: A node (260) for an optical communications network in which a token is passed between nodes, indicating that a corresponding optical channel is available for transmission during a token holding time while that node holds that token, until it passes the token to another node. A transmit controller (290) determines a traffic class of said packet and controls a buffer to forward a packet from the buffer to the transmitter according to the traffic class, if there is sufficient of the token holding time remaining before the received token must be passed on to another node for said packet to be transmitted by the transmitter over an optical channel corresponding to the received token. By having the packet forwarding dependent on traffic class, packets can be handled differently to suit different characteristics of the traffic classes.

Abstract: A method and apparatus for providing link establishment in the access segment of the communications network using broadband multi-wavelength LED are disclosed. In one embodiment, such links may be established in point-to-point, point-to-multipoint, multipoint-to-multipoint, or ring format depending on the topology required for optimized access network build-out.

Abstract: According to one general aspect, an interconnection node may be configured to dynamically provide interconnection access between a first optical network (e.g., a core optical network) and at least either a second optical network (e.g., an access optical network) or a third optical network (e.g., another access optical network) in a purely optical fashion. The interconnection node may include a first network portion and a second and third network portions. The first network portion may be coupled with the first network that includes a first pair of wavelength cross-connect (WXC) units coupled between a first transmission path of the first network, and providing a plurality of add and drop ports, and a second pair of wavelength cross-connect (WXC) units coupled between a second transmission path of the first network, and providing a plurality of add and drop ports.

Abstract: Embodiments of the present invention are directed to optical broadcast systems. The nodes of the system can be any combination of cores, caches, input/output devices, and memory, or any other information processing, transmitting, or storing device. The optical broadcast system includes an optical broadcast bus. Any node of the system in optical communication with the broadcast bus can broadcast information in optical signals to all other nodes in optical communication with the broadcast bus.

Abstract: A method for dynamic routing an optical signal in an optical network is provided, including: executing a shortest-path algorithm receiving input concerning a source node, a destination node and the topology of the network, providing a shortest-path tree comprising nodes and arcs connecting the nodes, the shortest-path tree comprising branches along which an effective attenuation is no greater than a predetermined limit, each branch comprising an end node and each end node being associated with a corresponding set of wavelengths; checking, for each end node having no wavelength conversion resources and for each wavelength, if the end node is connected to at least another node external to the branch through the wavelength; excluding, for any end node if the result of the checking is negative for at least one wavelength, the at least one wavelength from the corresponding set of wavelengths, thus updating the topology; and re-executing the shortest-path algorithm.

Abstract: A system and method for handling accesses by nodes connected to a ring network, using time division multiplexing (TDM). The system includes: nodes capable of receiving only an optical signal of a wavelength or positional space allocated to the node, and of transmitting optical signals of wavelengths allocated to other nodes; and a ring network that performs TDM transmission of optical signals. The ring network has slots for transmitting optical signals of individual wavelengths. Information indicates whether an optical signal to be transmitted exists in each of the slots. Nodes include means for updating the information indicating that the optical signal exists and determining means for updating the information and determining, on the basis of the information, whether to transmit the optical signal.

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 topologies, optical nodes, and optical junction nodes to efficiently allocate bandwidth within the data center networks, while reducing the overall physical interconnectivity requirements of the data center networks.

Abstract: An optical ring network architecture including a number (N) of multi-add/drop filters, such as filters formed using pairs of frequency routers. Each multi-add/drop filter is coupled to two other multi-add/drop filters using N?2 transmission media, such as optical fibers, to form a ring. The network includes a number (N) of terminal stations associated with the multi-add/drop filters. A terminal station (p) is coupled with, and receives information from, its associated multi-add/drop filter (p) through a single optical fiber. The terminal station p is coupled with, and transmits information in a first direction around the ring to, a multi-add/drop filter p+1 through a single optical fiber. Communications from terminal station p to each other terminal station in the first direction are assigned one of N?1 wavelengths where no two wavelengths on a given optical fiber are associated with communications between terminal stations in the same direction.

Abstract: An optical communication network node apparatus is provided that considerably reduces the node apparatus in scale, especially, a switch device in scale relative to increase in the number of wavelength multiplexes.

Abstract: When a frame is received from one of PON ports 12a to 12c of ONUs 1a to 1c, an OLT 3 compares VPIDs contained in Preamble/SFD regions A of the received Ethernet® frame with VPIDs assigned to LAN ports 31 and 32 of the OLT 3. Upon coincidence, a PON MAC process is started. When a frame is received from a PON port 33 of the OLT 3, each of the ONUs 1a to 1c compares a VPID contained in a Preamble/SFD region of the received Ethernet® frame with VPIDs assigned to the ONUs 1a to 1c. Upon coincidence, a PON MAC process is started.

Abstract: A microwave radio assembly is described including a directional antenna wherein the installation and aiming is simplified. The assembly is attached to the wall-mount fix via gimbals mechanism with one rotation axis for azimuth and one for elevation and the assembly preferably includes a sight mechanism including a pair of visual apertures is located in the radio assembly in a line parallel to the radio antenna radiation direction. The radio assembly further includes a modulation cancellation scheme in full duplex mode.