Abstract: A method and system for transporting traffic in a packet-switched network segments high priority pass-through traffic from low priority pass-through traffic. The high priority pass-through traffic is transmitted on an egress link preferentially over the low priority pass-through traffic and ingress high priority local traffic. The ingress high priority local traffic is transmitted on the egress link preferentially over the low priority pass-through traffic.

Abstract: A method and system for controlling the gain of the amplification of an optical signal is provided that includes both electrical feedforward and feedback. In a feedforward portion of an optical amplifier, the method includes receiving an optical signal and measuring an input power. Based on the measured input power and a desired gain, a feedforward pump power is determined. The pump power is adjusted based on the determined pump power. In a feedback portion of an optical amplifier, an output power is measured and gain is determined based on the output power and the measured input power. The measured gain is compared to a desired gain and the pump power is adjusted based on that comparison.

Abstract: An apparatus and method for generating via integer calculations a metric for estimating link utilization within a network device having at least one output port. The metric is determined by calculating at least three data rate link parameters for a given sampling period. The data rate link parameters include an error data rate parameter, an average data rate parameter, and a deviation data rate parameter. These parameters are determined using integer values and integer operations and may be used by a link management system for performing load balancing among a plurality of output ports and for determining whether to forward low priority data traffic via a particular output port.

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: In a system using simple network management protocol, elements report events to a network management system using a generic trap structure. The trap structure includes fields for identifying details on an object experiencing an event and detailing the event, and potentially includes management information for tracking individual trap messages.

Abstract: A serial bus communication system for communication across the backplane of a node includes a control unit having a serial bus controller. 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: A multiported integrated circuit performs pointer processing at the SONET STS and VT levels, and removes overhead information from a received electrical signal derived from an optical SONET signal. The integrated circuit operates to extract STM traffic and ATM traffic from the received SONET signal, in response to provisioning information received from a management and control unit. The extracted STM traffic is then combined with path switching information, and forwarded out a pair of interfaces, which enables path selection within an STM switch fabric within a local line unit and within a switch fabric on a partner line unit in an active/standby pair of line units. The path switching information is also output from the integrated circuit for transmission to a pair of ATM switch fabric units.

Abstract: In accordance with one embodiment of the present invention, a map of transmission slots for a port of a network element includes a plurality of hierarchical sets of port transmission slots. The hierarchical sets include a plurality of parent sets. Each parent set has its port transmission slots divided between a plurality of child sets. The child sets include interleaved port transmission slots.

Abstract: Congestion management is provided using one or more receive queues organized into a queue list. Each queue is associated with a high water mark and a low water mark. The high water mark indicates a length at which the queue is considered congested. The low water mark is a length at which a congested queue is considered no longer congested. When a queue reaches or exceeds its high water mark, newly arriving frames destined for that queue which are eligible for discard are dropped. Frames arriving not marked as eligible for discard are enqueued at the queue's tail. Queues in the queue list are organized by relative priority. When a single queue above a predetermined priority is determined to be congested, all queues in the queue list are treated as congested. Congestion in lower priority queues results in only the individual congested queue being treated as congested.

Abstract: A system includes a communication device that includes a number of interface cards and a switching complex. Upon receiving a data signal, an input card modifies header bits of the data signal to identify an input port on which the data signal was received. The switching complex uses the modified header bits to communicate the data signal to an output card and associated output port. In a particular embodiment, the switching complex may also modify header bits to identify the input card.

Abstract: The method for handling call set-ups in a telecommunication network includes receiving a request to set up a call. The method also includes comparing a dynamic load value for a switch to a load threshold for the switch. The method further includes allowing the call to be set up when the dynamic load value is less than the load threshold.

Abstract: A congestion control mechanism in an ATM network access device includes segmentation and reassembly (SAR) logic that sends and receives Asynchronous Transfer Mode (ATM) cells to and from interface logic that transfers the cells to and from a switch fabric. The cells are transferred on ATM connections, including flow-controlled connections for which the sending of cells by the SAR logic is controlled in response to the settings of Generic Flow Control (GFC) bits appearing in the headers of ATM cells received by the SAR logic. The interface logic receives a congestion signal indicative of the level of congestion in a transmit buffer in the switch fabric. In response to the congestion signal, the interface logic sets the GFC bits in the headers of cells transferred to the SAR logic such that the cell transmission rate is maintained at a high average level while undesirable congestion in the transmit buffer is avoided. Hysteresis is employed in the setting of the GFC bits is response to the congestion signal.

Abstract: A network element management system which automatically configures itself, when an operator enters a component identifier, for optimal full-featured management of the identified component. This is preferably done by an autodiscovery process, and not by any mere lookup.

Abstract: A crosspoint switch uses an iterative process to deliver multicast packets from inputs to outputs. The switch includes output queues dedicated to the inputs, with backpressure indications provided from the output queues to the corresponding inputs. The inputs use the backpressure indications to schedule multicast packets for delivery to one or more of the output queues.

Abstract: In accordance with one embodiment of the present invention, a network element comprises a first subsystem operable to receive management transactions in a first management protocol and to map the transactions to a common management protocol. A second subsystem is operable to receive management transactions in a second management protocol and to map the transactions to the common management protocol. A common management information base (MIB) includes a dataset and a common interface to the dataset. The common interface is operable to access the dataset to process transactions received from the first and second subsystems in the common management protocol.

Abstract: A method and system for controlling the gain of the amplification of an optical signal is provided that includes both electrical feedforward and feedback. In a feedforward portion of an optical amplifier, the method includes receiving an optical signal and measuring an input power. Based on the measured input power and a desired gain, a feedforward pump power is determined. The pump power is adjusted based on the determined pump power. In a feedback portion of an optical amplifier, an output power is measured and gain is determined based on the output power and the measured input power. The measured gain is compared to a desired gain and the pump power is adjusted based on that comparison.

Abstract: A system for allocating bandwidth in a network element. The system determines whether a bandwidth allocation request is associated with a delay sensitive connection type. If so, the system selects a bandwidth allocation algorithm from a first set of bandwidth allocation algorithms. Otherwise, the system selects a bandwidth allocation algorithm from a second set of bandwidth allocation algorithms. The size of the bandwidth allocation request may be examined when selecting which bandwidth allocation algorithm to use. The system may round up the size of the bandwidth allocation request to a predetermined value. The selected bandwidth allocation algorithm may reserve slots in a bandwidth allocation table. Reserved slots that are equally spaced in the bandwidth allocation table avoid undue delays in servicing an associated connection. A binary tree representation of the table is described, wherein leaves of the binary tree correspond to individual table slots.

Abstract: Telecommunication equipment includes a TDM interface operable to receive STS-n data, and a packet interface operable to receive packet/cell data and filling a STS-MC payload with the packet/cell data. An n×n cross-connect is coupled to the TDM interface and operable to switch and assign the STS-n data to any one of n STS-1 time slots. A multiplexer is coupled to the cross-connect and the packet interface and operable to combine the switched STS-n data and the STS-MC packet/cell data into an STS-N payload for transport, where N is the sum of n and M.

Abstract: A method perfomed by an ingress card includes receiving a packet with a destination identifier, and determining an aggregated link associated with the destination identifier that includes multiple egress ports. The method further includes determining a destination port from the egress ports of the aggregated link, and communicating the packet to the destination port.

Abstract: A method for routing traffic in a network includes determining topology information for the network and determining traffic demands for multiple service classes. The method further includes determining an objective function for an optimization problem using the topology information and demands, and determining a solution to that specifies a network path for each demand.