Abstract: An optical ring is operable to transport traffic signals between nodes. A Raman pump source is coupled to the optical ring. The Raman pump source is operable to provide pump power to at least a portion of the optical fiber ring. Each node comprises an optical splitter operable to at least passively drop traffic to the optical fiber ring. Each node further comprises a pump filter operable to separate at the node the pump power from traffic signals.

Abstract: A method for monitoring the operating temperature of an item on a card shelf having a plurality of discrete electronic cards includes receiving a measured temperature for an item on a card shelf that is indicative of an operating temperature of the item. The method also includes determining whether the item is operating above a specified limit using the measured temperature and information stored in a memory that relates the measured temperature to the operating temperature of the item. Furthermore, the method includes determining whether there has been a restriction of air flow through the card shelf in response to determining whether the item is operating above a specified limit.

Abstract: A highly available communications system capable of circuit reestablishment and tear-down without manual intervention. The communications system includes a plurality of nodes interconnected by a plurality of communications paths to form at least one communications network. The nodes forward control packets on the network by way of a signaling protocol employing an out-of-band control technique. At least a portion of the nodes comprises a software configuration including a topology manager and a protocol manager. The protocol manager is operative to determine whether a control path is operational and whether a data transmission channel along a corresponding data path is established. In the event the control path is not operational, the protocol manager maintains the data transmission channel along the data path so long as the channel is established.

Abstract: A method for transporting packet-switched control traffic in an optical network includes receiving a packet-switched datagram comprising a destination address. The method also includes identifying a destination Open Systems Interconnection (OSI) address of a destination network element in the optical network based on the destination address of the datagram. In addition, the method includes generating an OSI packet comprising the datagram and the destination OSI address, and transmitting the OSI packet on the optical network in an OSI channel of a Synchronous Optical Network (SONET) frame.

Abstract: An add/drop node (OADN) comprises a network optical fiber carrying a signal on an optical network. A network drop splitter is coupled to the network optical fiber and to stages of drop splitters, the stages of drop splitters being operable to passively split an optical signal from the network drop splitter into multiple copies of the signal. The OADN further comprises at least one filter operable to receive at least a copy of the signal from at least one drop splitter to create a filtered copy, and further comprises at least one broadband receiver operable to receive the filtered copy from the filter.

Abstract: A method for handling call set-ups in a telecommunications network. The method includes receiving a request to set up a call. A dynamic load value is compared to a load threshold. The call is allowed to be set up when the dynamic load value is less than the load threshold.

Abstract: An optical communication system includes a plurality of nodes coupled by an optical fiber. The optical fiber comprises a gain medium and is operable to transmit optical signals in a plurality of channels. An optical pump is coupled to the optical fiber, and is operable to generate and transmit an optical pump signal co-propagating with the optical signals. The optical pump signal comprises a specified walk-off with respect to the optical signals and is operable to Raman amplify the signals in the optical fiber while maintaining an eye penalty below 0.5 decibels.

Abstract: A sub-network of a communication network includes four nodes, with each node having two input ports and two output ports. The first node and the fourth node each link both of their input ports and one of their output ports to other nodes of the sub-network, with each of their remaining output ports operable to send signals outside of the sub-network. The second and third nodes link both of their output ports and one of their input ports to other nodes of the sub-network while each of their remaining input ports is operable to receive signals from outside of the sub-network.

Abstract: In an optical communication network, optical communication nodes exchange information detailing power level variations to support management and administration of optical communications. This exchange of information permits nodes to determine aggregate power level variations over light paths to support operations such as selection from available light paths and configuration of optical communication characteristics.

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: In an optical communication network, optical communication nodes exchange information detailing power level variations to support management and administration of optical communications. This exchange of information permits nodes to determine aggregate power level variations over light paths to support operations such as selection from available light paths and configuration of optical communication characteristics.

Abstract: In an optical communication network, optical communication nodes exchange information detailing power level variations to support management and administration of optical communications. This exchange of information permits nodes to determine aggregate power level variations over light paths to support operations such as selection from available light paths and configuration of optical communication characteristics.

Abstract: A method for monitoring the operating temperature of an item on a card shelf having a plurality of discrete electronic cards includes receiving a measured temperature for an item on a card shelf that is indicative of an operating temperature of the item. The method also includes determining whether the item is operating above a specified limit using the measured temperature and information stored in a memory that relates the measured temperature to the operating temperature of the item. Furthermore, the method includes determining whether there has been a restriction of air flow through the card shelf in response to determining whether the item is operating above a specified limit.

Abstract: A method and system for forwarding packets within containers in a data communication network. Each container may include packets or additional containers. Packets/containers are stored within containers in a predetermined format that includes a Type field, a Length field and a Value field. The Type field includes an indication whether the respective packet/container is the last packet/container in the respective sequence. The Length field specifies the Length of the following Value field and the Value field comprises the payload, which may comprise additional packets or containers. A header, such as an MPLS shim header, is applied to containers to be transmitted over the network. Containers are closed and scheduled for transmission once when it is determined that the addition of a packet/container to the overall container would exceed a predetermined maximum container size or when a timer measures a predetermined time period from the arrival of the first packet within the container.

Abstract: A method and system for communicating traffic on an emulated subnetwork of a telecommunications ring having a plurality of nodes interconnected by a transmission media includes obtaining traffic at a node on the telecommunications ring. The traffic is segmented into a plurality of discrete segments. A set of broadcast cells is generated by adding an address header to each segment. The address header identifies a virtual channel dedicated to the node on the subnetwork in the telecommunications ring. The set of broadcast cells are transmitted in the virtual channel of the subnetwork and within a frame of the telecommunications ring. At each remaining node on the telecommunications ring, in response to receiving the set of broadcast cells in the virtual channel, both retransmitting and processing the broadcast cells.

Abstract: A system is provided for providing a protection path for connection-oriented signals in a telecommunications network comprising a plurality of nodes. The system includes a source node, a destination node and a penultimate node. The source node is operable to transmit traffic. The destination node is operable to receive traffic from the source node. The penultimate node is operable to receive traffic from the source node, to transmit traffic directly to the destination node, to designate one of the nodes as a reflector and to generate a first segment of a protection path from the penultimate node through the reflector to the destination node.

Abstract: An optical modulator for generating an optical information signal includes a first modulator that modulates an optical carrier with a clock signal. The optical modulator further includes a filter that suppresses a residual carrier component of modulated optical signals. In addition, the optical modulator includes a second modulator for modulating an optical signal with a non-return to zero data signal. When combined, the first and second modulator and the filter operate to transform an optical carrier signal into an optical information signal that is highly tolerant to dispersion and non-linear effects in optical fibers.

Abstract: A method for protection switching includes receiving an optical signal from a transponder coupled to a client and optically splitting the signal to a first output and a second output. The first output is coupled by a first optical add-drop multiplexer to a first optical fiber, and the second output is coupled by a second add-drop multiplexer to a second fiber. The method further includes selecting one of the output signals for the working channel, and communicating the selected output signal to an optical network. During communication of the selected output signal to the optical network, the method includes monitoring for a failure condition in the optical network and, if the failure condition is detected, selecting the other output signal as the working channel and communicating the new selected output signal.

Abstract: A serial bus communication system for communication across the backplane of a node includes a control unit having a serial bus controller operable to convert between parallel signals and serialized signals. A plurality of service units each include a serial bus terminator. A serial bus includes a discrete serial channel for each service unit. The serial channel connects the serial bus terminator to the serial bus controller. The serial bus controller is operable to direct a message for a service unit on the serial bus to only the serial channel of the service unit.

Abstract: In an ATM communications system, a cell entering a switch fabric input port is routed to its destination output port and to a predetermined dedicated second output port. The second output port is connected by a feedback connection to a predetermined dedicated second input port. The cell can then be either switched to the same destination output port or switched to both the same destination output port and the predetermined dedicated second output port, thereby providing the ability to execute a logical multicast with any number of leaves to the destination output port.