Abstract: A method and system for allocating bandwidth in an optical communication system. During a set-up phase, a set-up message including requesting a connection is generated and includes a requested priority and requested bandwidth. When a switch receives the set-up message, the switch determines whether the available priority bandwidth for the requested priority exceeds the requested bandwidth. If the available priority bandwidth for the requested priority exceeds the requested bandwidth, the switch creates a provisional connectional which is committed to an actual connection in a subsequent connect phase. If the available priority bandwidth for the requested priority does not exceed the requested bandwidth, then the switch rejects the connection to provide a fast release.

Abstract: A combined wide area network (WAN) port/synchronization unit that receives inputs including data and timing information and that synchronizes the data for transmission. The unit includes the following components. A network interface receives the input and removes data and primary timing information from the input. A data-path function processes the data. A reference selection unit receives timing information from the network interface as well as timing information from a secondary combined WAN port/synchronization unit. A synchronization control unit selects the most reliable timing information from the plurality of timing information inputs to the reference selection unit. A multiplexor multiplexes the timing information with the processed data across a link.

Abstract: The present invention is directed toward a distributed intelligence fiber-optic communication network in which node control processors (NCPs) associated with each network element periodically transmit identification and status information to the other NCPs in the network. Various faults in the network can thus be readily identified, and appropriate tasks for modifying the network in response to the fault (such as rerouting around a defective network element) can be carried out. Further, information continues to be distributed among the NCPs even if a break occurs in a segment of fiber in the network.

Abstract: The present invention provides a method and apparatus for implementing distributed user management information in telecommunications networks. At least a portion of a user's management information is stored in a team session file that is accessible by a network management system (NMS) client. For example, the team session file may be saved in memory that is local to the NMS client or, if a user logs in through a remote system using a web browser, the team session file may be saved as a cookie in memory local to the remote system. The NMS client may then utilize the user management information in the team session file while the user is logged into the NMS client. In one embodiment, the user management information stored within the team session file includes NMS server connection information. Thus, when a user logs into an NMS client, the NMS client uses the NMS server connection information to connect to an NMS server.

Abstract: A digital subscriber line access multiplexer overlay onto a digital loop carrier system for transporting high speed digital data over an existing backplane which carries voice, data, and test signals between voice line cards and a carrier line. The voice signals are time division multiplexed into frames. The system includes a data bus interface for impressing the high speed data on a subset of existing backplane buses for transport along the backplane and for retrieving high speed digital data from the backplane buses. The system further includes a plurality of data line cards for connecting to the backplane and backplane subset conductors, the data line cards being adapted to couple the high speed data between the subscriber line and the backplane, whereby the high speed digital data can be routed over the backplane subset to any of the digital data line cards without interfering with the voice signals routed to voice line cards.

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: The present invention provides a gratings-based add-drop multiplexer in which plural optical channels can be added and/or dropped by the same optical device in a manner which avoids transmitting an optical channel through a radiation mode loss region of a Bragg grating. In one embodiment, the add-drop multiplexer comprises a three-port optical circulator, an optical coupler, and a transmission path communicating with both the circulator and the optical coupler. A set of one more Bragg gratings is positioned in the transmission path for reflected signals to be dropped towards the circulator and onto a "drop" path. The through optical signals enter the first coupler input port and are combined with the "add" signals transmitted by the second coupler input port. The coupler optically combines these optical signals and outputs the combined optical signal.

Abstract: The present invention provides a bidirectional WDM optical communication system with bidirectional optical amplifiers for optically amplifying two counter-propagating WDM optical signals. The bidirectional WDM optical communication system includes a first set of optical transmitters for creating a set of east-west optical channels and a second set of transmitters for creating a set of west-east optical channels. The respective channel sets are multiplexed by optical combiners and output to an optical transmission path. A bidirectional optical amplifier optically communicates with the optical transmission path for amplifying the east-west and west-east WDM signals. In an exemplary embodiment, the bidirectional optical amplifier comprises a first and second four-port optical circulators and a section of doped optical fiber with optical pumps interconnecting the two circulators.

Abstract: A WDM optical communication system is described which is capable of placing information from incoming information-bearing optical signals onto N optical signal channels for conveyance over an optical waveguide. The optical system includes a first set of one or more optical transmitters, each of which emits an information-bearing optical signal at one or more transmission wavelengths, .lambda..sub.Ti. At least M optical receiving systems are provided, each receiving system configured to receive an information-bearing optical signal at a particular reception wavelength .lambda..sub.j, where M is a whole number greater than or equal to N and j is from 1 to M. Each receiving system includes at least one Bragg grating member for selecting the particular reception wavelength .lambda..sub.j. An optical waveguide optically communicates with each of the M receiving systems for transmitting a plurality of optical signals.