Abstract: An interface for communications among network elements of at least one network is provided, comprising at least one transmitter, at least one receiver, at least one processor, and at least one backplane coupled among the network elements. Data frames of a second type, or Time Slot Network (TS Net) data frames, are generated and transferred over the backplane in response to receipt data frames of a first type from the network. The TS Net data frames comprise switching event information. Compare operations are performed among prespecified TS Net data frames at prespecified intervals, and at least one interrupt signal is generated in response to data changes determined by the compare operations. Information routing is controlled over the network by a processor in response to the interrupt signal.

Abstract: A method for tensioning and positioning a fiber optic cable includes providing and securing a first portion of the fiber optic cable in a first support with a first clamp. A second portion of the fiber optic cable is then provided in a second support, and secured thereto with a second clamp. A cam contacting the second support is then rotated, thereby rotating the second support due to its weight and the weight of the second clamp. The rotation of the second support creates a gravity-assisted moment arm that uniformly and repeatably tensions and positions the fiber optic cable. After the fiber optic cable is uniformly tensioned and positioned, a refractive-index grating may be etched in the glass optical fiber portion of the cable. Once the grating is etched, the cable may be removed by reversing the method.

Abstract: A method that mass polishes a variety of fiber optic cable connectors simultaneously. The method includes a plurality of steps for mass polishing of fiber optic cable connectors with varying patterns and loci of motion to prevent overlap of patterns during polishing. Thus, fiber optic cable connectors having a variety of polished end faces may be provided with the apparatus. The method also eliminates the potential for contamination among polishing films, reduces polishing steps, and saves labor and maintenance costs.

Abstract: Systems and methods consistent with this invention allow for each node within one or more rings to obtain connection and topology information from other nodes within these rings. In such a system, each node is able to maintain connection table and topology tables for each node and each ring within a ring network. In particular, such information can be kept current because this scheme allows for dynamic updating of connection and topology information in real time. With such current information, a node is able to utilize this information to execute such operations as squelching connections on a protect line and timeslot interchange. In addition, by supporting timeslot interchange, the ring can be managed as more than a single logical entity as well as can have better bandwidth management utilization.

Abstract: System for adjusting a power level of an optical signal at an input to a component in a network element that forms part of an optical network. The system includes a variable optical attenuator (VOA) for receiving a first optical input signal and producing an attenuated optical output signal. A detector is coupled to the input of the component for detecting a power value of a second optical input signal that is derived from the attenuated optical output signal. A VOA controller (VOAC) includes logic for receiving the power value, via a signaling channel, and generating selected control parameters that are input to a control input of the VOA for accordingly adjusting a VOA attenuation factor to achieve a selected signal power level at the input to the component.

Abstract: A unidirectional ring operates in accordance with a call setup procedure in which a single node on the ring, referred to herein as the “hub node,” simultaneously (i) processes call setup information from and provides call setup information to an ATM network, and (ii) controls the call setup operations of the nodes on the ring. When a source node that is part of the ring initiates a call, the node directs a call setup message to the hub node. The hub node determines if there is sufficient bandwidth available on the ring for the call. If so, the hub node passes the call setup message to the ATM network, and simultaneously multicasts call setup information to the nodes on the ring. While the call setup message is progressing over the ATM network in a conventional manner, the nodes on the ring simultaneously set up the associated virtual path and/or virtual circuit and send back connection information to the hub node.

Abstract: A serial data signal having a predetermined sequence to indicate a start of a frame of data is received. The serial data signal is compared to a plurality of values. The plurality of values include the predetermined sequence and one or more values representing logical rotations of the predetermined sequence. A match signal is generated in response to the serial data signal matching one of the plurality of values.

Abstract: A network optimization method measures the line bit error rate (BER) at a receiver by counting forward error correction corrected errors, and adjusts network parameters to minimize the corrected error rate. Adjustable parameters include, among other things, transmitter extinction ratio, transmitter polarization, and dispersion. The method includes sweeping an adjustable parameter while monitoring the FEC corrected bit error rates at the receiver, and then extrapolating an optimum value of the parameter. In this way, the corrected BER can be maintained below the predetermined BER limit while the digital communication network is in-service.

Abstract: An optical fiber ring is provided carrying a plurality of WDM optical signals, each at a respective one of a plurality of wavelengths. Each optical signal carries data associated with a corresponding group of TDM add/drop multiplexers coupled to an optical path spaced from the optical fiber ring. The optical signals are extracted from the fiber ring with optical add/drop multiplexers, and the data carried by the optical signals is then supplied to the corresponding group of TDM add/drop multiplexers. Accordingly, instead of assigning an optical add/drop multiplexer to each TDM add/drop multiplexer, the optical add/drop multiplexers are assigned to respective groups of TDM add/drop multiplexers. As a result, optical loss as well as cost of the WDM ring are minimized.

Abstract: The dynamic range of an optical amplifier is extended by the addition of a power control circuit. A switch is interposed between a current source and an optical pump supplying pumping light to the gain medium of the optical amplifier. A modulated signal such as a pulse-width modulated signal is used to actuate the switch and control a relative duration of the “on” and “off” periods of the electrical current supplied to the optical pump. Gain latency in the optical amplifier permits a substantially continuous signal to be output from the optical amplifier in response to the switched electrical current supply to the optical pump. A controller may used a feedback signal from the optical pump or from a power monitoring device to control the modulator and, thereby, the switch. A target pump power level, target gain or target amplified signal power level may also be applied in a feedback control loop that controls the modulator and switch.

Abstract: A first network element includes or is associated with a query engine that allows it to retrieve operating parameters from a second network element even when the first and second network elements are not participating in a common routing protocol. The first element is thereby able to infer the quality of data signals passing through it and take configuration action in response to an operational problems. In one embodiment, a preexisting management agent in the second element is utilized by the first element and modification or enhancement of the second element is not necessary.

Abstract: Disclosed herein are fiber optic cable clips for securing and routing fiber optic cables on a printed circuit board (PCB) or other component used in the communications field. One fiber optic cable clip includes a U-shaped body connected to attachment legs that permanently connect to the PCB. The U-shaped body defines a containment area for receiving and retaining fiber optic cables. The U-shaped body also includes spring-loaded arms or pads that flex open to permit entrance of the fiber optic cables into the containment area, and flex close to retain the cables therein. The fiber optic cable clips retain multiple cables, are easy to use, and do not damage the cables when installing the cables within the clip. If the fiber optic cables are pulled when contained within the clip, the fiber optic cable clips will flex and release the cable before the cables are damaged.

Abstract: A switch is provided that receives user information through a plurality of framer circuits, which group the user information into frames. The frames are fed to a switch fabric including an array of switch elements, each having a switch matrix for routing each frame to a desired output in accordance with configuration data stored in a first table coupled to the switch matrix. If different outputs are desired, i.e., the switch matrix is to be reconfigured, a switch control circuit supplies additional switch configuration data to the frames through the inputs along with additional user information to be routed through the switch. While the additional switch configuration data is stored in a second table, data flow remains uninterrupted through the switch matrix.

Abstract: A system for managing signal power levels in an optical network. The optical network comprises a plurality of nodes having logic to receive and transmit optical signals over a plurality of network interconnections. The system includes a method wherein each of the nodes is provided configuration parameters, each of the nodes is configured based on the configuration parameters, power parameter information is exchanged between the nodes, at least some of the nodes are re-configured based on the power parameter information and the steps of exchanging power parameter information and re-configuring at least some of the nodes are repeated until the optical network is fully configured so that the optical signals have selected signal power levels.

Abstract: A method and apparatus for performing parallel asynchronous testing of a plurality of optical modules utilizes state machines that may be implemented in a common controller. Desired optical tests are selected by an operator. The invention determines if a testing process or instrument required for the selected optical tests is available. A COM port may also be locked for each of the selected optical tests from among a plurality of COM ports to prevent interference between different tests. By reserving resources such as COM ports and testing instruments in this fashion the invention may asynchronously initiate execution of the selected optical tests. If a resource such as a COM port, testing process or instrument is not currently available, the test is place in COM port and testing queues to await availability of that resource. Once a test is completed, the resource is unlocked so that one of the state machines may asynchronously initiate another test.

Abstract: A method described in this document enables building a (logical) SDH/SONET ring where the connections between the packet-switched Access Interfaces of the SDH/SONET ring are automatically and dynamically (at 1 ms time-scale) arranged based on the actual volumes of the packet traffic flows between the Access Interfaces of the SDH/SONET ring and fair sharing of network resources. Traffic prioritizing is possible within the Access Interface to Access Interface traffic flows. No packets are lost in the SDH/SONET ring, unless temporarily in case of line or equipment failure.

Abstract: A module for holding a printed circuit board (PCB) includes rectangular-shaped, mating top and bottom brackets. Three walls of the top bracket retain SMA connectors that interconnect with the PCB. A dielectric gasket is provided below each SMA connector to provide pressure on the leads thereof so that the leads adequately contact corresponding pads on the PCB. Two walls of the bottom bracket include channels that slidably receive and retain the PCB therein, and another wall includes a stop channel that retains an edge portion of the PCB when the PCB is slid through the channels. The bottom bracket also has diamond-shaped pads and a square-shaped pad connected between two walls thereof that align with and support corresponding components provided on the PCB and dissipate heat generated thereby. A cable connector provided on one end of an electrical cable connects to each SMA connector, and the other ends of the electrical cables connect to testing equipment.

Abstract: A method of controlling an optical fiber splicing machine utilizes a power control mode to control the amount of power delivered to fuse the fibers. In the power control mode, the attenuation is measured while the fusing process is occurring. A rate of attenuation loss is predicted from the measured attenuation values by using an estimator. If the rate of attenuation loss indicates that a threshold insertion loss will be crossed before the next attenuation measurement, the splicing machine is stopped prior to the next attenuation measurement. If the desired attenuation is not achieved, an energy control mode is utilized which controls the amount of energy delivered to fuse the fibers. After delivering this energy, the method measures the attenuation. If not within desired values, the energy mode is repeated. At each iteration the splicing control function utilized by the energy control mode may be reprogrammed. A PID control formula may be used to determine the arc current for each iteration.

Abstract: A fiber optic cable management system that may be provided in a bay (or shelf) of an optical communications housing. The fiber optic cable management system includes at least one and preferably several interconnecting fiber optic cable guides. Each fiber optic cable guide includes a radius limiting portion that prevents fiber optic cables from being bent beyond their minimum bend radii. The radius of the radius limiting portion of each guide controls the spacing between a specific guide and its adjacent, interconnecting fiber optic cable guides. The width and height of each fiber optic cable guide may be varied depending upon the optical communications system into which the fiber optic cable management system is utilized. The interconnecting fiber optic cable guides may be easily disconnected from each other to allow the fiber optic cable guides to be used in different quantities. This allows an installer to customize the fiber optic cable management system to match the optical communications equipment.

Abstract: An optical amplifier control circuit and method controls transients and avoids the problems associated with measuring gain. The input power level is detected and amplified by a transient control setting to provide a desired gain value against which is compared the output power level. This transient control error may be used in conjunction with a constant power error and/or a constant current error such that the lowest of the error values is used to drive the pump laser. Current and power feedback signals and settings are used to derive the error values. Multiple pump lasers per stage may also be controlled and a multi-stage amp having a cascaded structure may be realized using the inventive techniques.