Abstract: An optical bus interconnects two or more processors in a multiprocessor system. One or more electrical-to-optical (“E-O”) transmitters are optically coupled to the optical bus using optical couplers. The E-O transmitters receive electrical signals from the processors and convert the electrical signals to optical signals to be guided onto the optical bus. Optical-to-electrical (“O-E”) receivers are also coupled to the optical bus using the optical couplers. The O-E receivers receive optical signals from the optical bus and convert the optical signals to electrical signals for the processors.

Abstract: An optical network provides a digital interconnect fabric allowing nodes to seamlessly communicate with each other. Each node is connected to a bi-directional optical bus through passive optical interface devices. The optical interface devices route signals from each node onto the bus in both directions and also route signals traveling along the bus in either direction to each node. The optical interface devices and optical bus are passive and do not involve any regeneration of the electrical signals. The nodes are assigned wavelengths of transmission and have tunable receivers for selecting a wavelength of reception. The digital interconnect fabric facilitates Ethernet, Fibre Channel, and other digital communication protocols.

Abstract: These teachings present triple data transport redundancy in the form of three data bus interfaces that are each designed and manufactured independently from one another and compatible with a common data handling protocol. This protocol can be one that includes no error correction. These interfaces can each couple to a corresponding first, second, and third data bus that may comprise optical data busses. Information gauges can be realized through use a memory that stores a plurality of images comprising views of an information gauge (or gauges) of interest showing a variety of different readings. Upon receiving information regarding a monitored parameter of interest (via, for example, the aforementioned data busses and data bus interfaces), this information can be used to address the stored information gauge view that corresponds to the present parameter value. That particular view can be recalled and displayed to thereby provide the corresponding information to a viewer.

Abstract: A method for optical supervisory signaling includes determining a wavelength channel status (WCS) value, a wavelength channel failure (WCF) value, and a wavelength channel lit (WCL) value for each one of multiple data channels services by an optical communication node. The method further includes communicating the values to a second optical communication node.

Abstract: A telecommunications mesh network includes a plurality of nodes each interconnected by an edge. A traffic demand is received having a working path with a link of edges interconnecting a source node with a destination node. The telecommunications mesh network has one or more pre-cross-connected trails associated therewith that are subdivided into one or more subtrails. Subtrails that do not meet pre-determined conditions are discarded. A logical graph representation of the telecommunications mesh network is created from subtrails that have not been discarded. Unused, shortcut, and rival edges are inserted into the logical graph. A shortest admissible protection path from the source node to the destination node is identified from the logical graph.

Abstract: In an optical transmission apparatus in which a plurality of nodes are optically connected to one another via an optical transmission path, a light signal which is coded so that a mixture ratio of 1 and 0 constituting data is made close to 50% is transmitted through the optical transmission path. When a light signal is not emitted from all of the nodes, a dummy signal which is an AC-like signal is emitted to the optical transmission path. Therefore, an optoelectric conversion section can be always set to an active state, and the signal recognizability can be prevented from being lowered.

Abstract: Wavelength assignment schemes that provide full-connectivity in RANs with fixed-tuned OADMs. In the first scheme, wavelengths are assigned to nodes according to Hadamard code, and in the second scheme, bands of contiguous wavelengths are assigned to nodes. Simulation results show that on the average, the Hadamard wavelength assignment schemes approach the performance of RANs with OADMs that add-drop all wavelengths, while saving 50% of the TDM terminals. The saving of TDM terminals by using wavelength tunable OADMs vary in different cases. Tunable OADMs are advantageous for lower traffic granularity and more interactions of a RAN with the outside network.

Abstract: A low-loss shared FTTH distribution network that enables optical communications within a subscriber area, including optical fibers routed from a point of distribution to the subscriber area, a tap device including an optical tap which interfaces a downstream optical fiber with a first optical fiber, and a straight-through optical fiber which is routed straight through the tap device. The tap device may include a splitter which splits the downstream optical fiber into multiple downstream optical fibers, and the tap device may include tap ports for the downstream optical fibers. Any number of straight-through optical fibers may be included which are routed straight through the tap device. A method including routing optical fibers within the subscriber area, tapping at least one optical fiber with a tap device to interface a downstream optical fiber, and routing at least one optical fiber straight through the tap device.

Abstract: An optical bus 30 optically connects each board of a signal processing section 22 and each board of a transmission/reception section 40 for transmitting an optical signal output to the optical bus 30 by each board of the signal processing section 22 to each board of the transmission/reception section 40 in a non-block state. In contrast, the optical bus 30 transmits an optical signal output to the optical bus 30 by each board of the transmission/reception section 40 to each board of the signal processing section 22 in a non-block state.

Abstract: A method and apparatus for scheduling the transfer of data bursts in a network comprising electronic edge nodes interconnected by bufferless core nodes are disclosed. Each edge node comprises a source node and a sink node, and each core node comprises several bufferless space switches operated in parallel. Each source node is connected to at least one core node by an upstream link that includes multiple upstream channels. Each core node is connected to at least one sink node by a downstream link that includes multiple downstream channels. Any of the space switches can have either an electronic fabric or a photonic fabric. Each space switch has a master controller, and one of the master controllers in a core node is designed to function as a core-node controller in addition to its function as a master controller. Each master controller has a burst scheduler operable to compute a schedule for the transfer of data bursts, received from source nodes, to destination sink nodes.

Abstract: Optical systems are provided. A representative optical system includes an optical transceiver with an optical source and an optical receiver. The system also includes an optical waveguide. At least one of the optical source and the optical receiver is optically coupled to an intermediate portion of the optical waveguide. The optical source provides optical signals for propagation by the optical waveguide, and the optical receiver receives optical signals propagated by the optical waveguide. Methods, optical transceivers and other systems also are provided.

Abstract: In a ring network comprising a plurality of nodes and a 16 channel coarse wavelength-division multiplexing (CWDM) plan, a technique is disclosed for adding and dropping channels that reduces the maximum attenuation loss that any channel encounters—thereby enabling longer rings to be constructed without using optical amplifiers in the ring. The 16 channels are typically distributed between the wavelengths 1310–1610 nm with 20 nm separation between channels. It is obscured that glass fibers have gradually decreasing loss at longer wavelengths in this band. The network includes a hub and several nodes that are interconnected by optical fibers in a ring configuration, where distance from the hub is the minimum value measure in either the clockwise or counterclockwise direction. Channels are assigned to the various nodes based on their wavelength. The channels whose wavelengths are near 1310 nm are assigned to nodes that are progressively closer to the hub.

Abstract: Disclosed is a novel free space optical communication system comprising an optical amplifier configured to amplify an optical signal received from a fiber optic cable, a transmitter coupled to the optical amplifier and configured to transmit the amplified optical signal across a free space medium. The system also includes a receiver configured to receive the attenuated optical signal and a second optical amplifier coupled to the receiver configured to amplify the attenuated optical signal before transmitting the optical signal on to a fiber optic cable. The optical amplifier is preferably a Raman optical amplifier, but may also be any other optical amplifier, or combination of optical amplifiers, known in the art.

Abstract: A memory circuit includes a plurality of memory cells, an input/output area for addressing or writing onto the plurality of memory cells by means of electrical signals, and an optical-electrical converter for converting optical signals into the electrical signals, the plurality of memory cells and the input/output area being integrated on a chip, and the optical-electrical converter being mechanically connected to the chip or being integrated into the chip.

Abstract: The present invention concerns a method to perform central control of in-line element (Ei) in a tree-like network by a line terminator (LT). A plurality of network terminators (NT1, NT2, . . . , NTi, . . . , NTn) are coupled via one or more of such in-line elements (Ei) to the line terminator (LT) by dedicated branches and by a common branch, respectively.

Abstract: The present invention includes an optical network unit ONU, connected to a backbone network including a host digital terminal HDT and a digital subscriber line access multiplexor DSLAM of a high-speed data service system, and connected to multiple subscribers, for performing subscriber concentration functions, while the ONU includes a common unit board CUB, interfaced with the backbone network, for extracting an ATM cell, performing a full-duplex ATM cell processing function, performing a transmission test for the ATM cell and associated data, and controlling mutual operations among each of the unit boards and data flows; multiple xDSL service unit boards for performing a subscriber interface after converting the ATM cell from the CUB to an analog signal and thereof, for dividing the ATM cell into a high frequency component for data area and a low frequency component for a voice area, and for transmitting the ATM cell to the subscribers, or vice versa; and a shelf including multiple slots for plugging-in mult

Abstract: An apparatus for determining an error ratio of individual channels of a WDM optical signal comprises a wavelength-selective filter for separating the individual channels of the WDM signal and a measurement circuit for measuring an error ratio of one channel using a first decision threshold level. The measurement circuit is operable to cycle through all channels, taking an error ratio measurement for each channel in sequence with a predetermined decision threshold level. Control circuitry alters the decision threshold level for successive cycles of the measurement circuit. The apparatus measures error ratio values for each channel in turn, building up an error ratio vs. threshold pattern enabling the Q value to be obtained. Although the time taken to build up the error ratio pattern for an individual channel is not shortened, measurements are taken on each channel at much shorter intervals.

Abstract: An optical switch for switching data in a network. The switch includes a housing. The switch includes a transmitter receiver means which transmits to or receives from the network the data. The transmitter receiver means is disposed in the housing. The first optical path forms a first closed optical loop along which the data flows in a first direction. The switch includes a second optical path forming a second closed optical loop along which the data flows in a second direction. The second direction is opposite the first direction. The first and second optical paths each having a portion in which the transmitter receiver means is inserted into or removed from the first and second optical paths without disruption of switching of data by the switch. A method for switching data in a network.

Abstract: A signal communication device for use within a computer includes a set of optical fibers configured to form an optical computer bus between a set of computer sub-system elements of a computer. A set of input optical connector cards are connected to the set of optical fibers. Each of the input optical connector cards includes a transmitting dynamic bandwidth allocator responsive to an optical bus clock signal operating at a multiple of a computer system clock signal such that a set of bus time slots are available for each computer system clock signal cycle. The transmitting dynamic bandwidth allocator allows a light signal to be applied to the optical computer bus during a dynamically assigned bus time slot. In this way, the optical computer bus bandwidth can be dynamically allocated to different computer sub-system elements during a single computer system clock signal cycle.

Abstract: The system includes optical bus-bridging devices for observing the modes of said electric buses and the modes of said optical fibers while said electric buses have not been driven (OFF mode), so that the modes of the two electric buses connected through optical fibers are brought into agreement and that the buses can be simultaneously driven by a plurality of nodes. While one or both of said electric buses have been driven (ON mode) by the nodes connected thereto, an optical output has been continuously produced from the buses that are being driven to said optical fibers, and while light has been inputted from said optical fibers, the modes of said buses are not observed, but an electric output is produced to the electric bus of the side to which light is inputted to drive the bus. The optical bus-bridging device changes the mode of the electric bus when the optical fiber does not change within a predetermined period of time after the optical bus-bridging device has outputted a signal to the optical fiber.

Abstract: Mechanisms for providing a subscriber-side interface with a passive optical network are described herein. An optical network termination (ONT) having an integrated broadband passive optical network processor is utilized to receive downstream data from an optical line termination (OLT) via a passive optical network and provide the contents of the downstream data to one or more subscriber devices via one or more data interfaces. Similarly, the ONT is adapted to receive and transmit upstream data from the one or more subscriber devices to the OLT via the passive optical network. Additionally, the ONT can implement a burst buffer for buffering upstream and/or downstream data. The ONT can be adapted to notify the OLT of the status of the burst buffer, thereby allowing the OLT to modify the bandwidth allocations.

Abstract: A data bus structure for cooperating with a plurality of nodes which are connected to each other. The data bus structure includes optical transmission modules associated with each node and a logical decision gate having inputs associated with each node. The logical decision output signal is provided in parallel to each node through the optical transmission modules. These modules serve to convert optical signals from the nodes to electrical signals and output to the logical decision gate and to convert electrical signals output from the logical decision gate to optical signals and output to the nodes. In order to separate a single node from the data bus, the transmission mode is monitored and an independently controlled switch is positioned between the logical decision gate and the optical transmission module. This arrangement functions to exclude a node from bus communication while leaving the remaining nodes uninterrupted.

Abstract: A communication system includes plural nodes interconnected with an optical transmission medium capable of carrying plural bands of optical channels. A device at each node is coupled to the medium for dropping one or more bands, adding one or more bands, and passively transmitting other bands such that a pair of nodes can communicate directly using a band common to the respective bands. One band of the bands associated with each of a first set of nodes overlaps with one band of the bands associated with each of a second set of nodes. Multiple overlapping bands provide a high level of wavelength termination diversity. An optical management bus system and method connects plural hybrid optical/electrical cables between transmission equipment and optical modules which connect to network fibers to provide a set of electrical connections that can be used to determine optical interconnections in an optical shelf configuration.