Abstract: In a network packet router having one or more ingress and egress ports, a method is implemented at an ingress port for egress pass/drop determination for packets, comprising the steps of (a) noting header combinations and values, and egress port destination for incoming packets; (b) comparing the header combinations and values with rule sets associated with the header combinations and values including egress port identities, and (c) returning a determination of pass or drop for the packet.

Abstract: A distributed Link-State Routing Protocol (LSRP) system in a packet switch having external communication ports has a first card executing Update process of the LSRP, making database updates, a second card executing Decision process(Shortest Path First (SPF)) of the LSRP, and a communication fabric coupling the cards with each other and the external ports. The LSRP may be an IS—IS system. In some embodiments there are additional cards involved, and the distribution of Link-State functions is over a set of multiple cards. Also in some embodiments there is a Location Service (LS) controller monitoring and configuring cards in the system.

Abstract: A modular and adjustable backplane assembly for providing a fiber-optics backplane interface to a plurality of router cards functioning as a data router is provided. The assembly includes a first portion having a first array of connectors for interfacing with a compatible array of second connectors engaging specific ones of the router cards, and a second portion having a second array of connectors for interfacing with a compatible array of second connectors engaging specific others of the router cards. The mechanics of the assembly enable a moveable attachment with respect to the first and second portions such that they may be positionally adjusted during mounting, and wherein external data paths are provided from individual ones of the connectors to individual others of the connectors by fiber-optic conductors.

Abstract: An inter-network method for distributing a path-vector routing protocol within a multi-processor router has steps of running an instance of a router-distributed Border Gateway Protocol (rdBGP) on each of a plurality of processors of the multi-processor router, establishing routing sessions between individual instances of rdBGP running on separate processors of the multi-processor router, and between individual ones of the instances of rdBGP and external protocol peers, exchanging routing information between instances of rdBGP and the external protocol peers, wherein the instances of rdBGP learn, from the external protocol peers, routes for a plurality of destinations, calculating independently, by each instance of rdBGP, a set of routes, including a best route, from each of the plurality of destinations learned from the external protocol peers, and sharing route information determined with the other instances of rdBGP running on separate processors in the multi-processor router, and updating route information

Abstract: In a network node having one or more packet processors and at least one CPU required to process specific types of packets, a system for managing the specific types of packets for CPU processing has one or more packet processors enabled to sort the specific types of packets into two or more categories of different priority for processing; and a queue set for queuing the sorted packets according to priority ahead of the CPU. The system is characterized in that the CPU processes the queued packets according to priority. In a special case the queues are a part of network access controller (NAC). Also in some cases a software component is provided for configuring the hardware.

Abstract: In a data packet router, a router fabric card for routing data packets is provided. The router fabric card comprises a plurality of ingress/egress ports, the ports connected through a switching facility for switching connection states of the port paths between individual ingress paths and individual egress paths on the fabric card, and a scheduling component for scheduling communication between ports on the fabric card. Data coming into ingress on the card is organized into individual data-packet trains, each individual train comprising data packets and inserted data denoting a starting point and an ending point of a train. The switching facility recognizes the start data and the end data of a train and switches port paths to a next-assigned connection state accordingly.

Abstract: A replaceable circuit breaker module has a housing for supporting and enclosing elements of the module, a circuit breaker mounted in the housing in a manner that an action of installing the module connects the breaker to bridge an incoming and an outgoing conductor, and monitoring circuitry for monitoring characteristics of the circuit breaker, the monitoring circuitry mounted in the housing and having a first connector element for engaging a mating connector element in the action of installing the module. The module is characterized in that action of withdrawing the circuit breaker module also withdraws the monitoring circuitry. Sensors in the monitoring circuitry may include sensors for monitoring one or more of breaker presence, on/off state of the breaker, and voltage provided to the breaker.

Abstract: A system and method for transferring data from a source to a destination are described. Data packets are split into multiple data packet portions and are transferred in parallel over parallel data streams or pipes to grouping circuitry where they are recombined into full data packets. Each packet portion is assigned a synchronization code and a pipe state machine state. The grouping circuitry reads individual packet portions from the parallel streams and analyzes the synchronization codes and the state machine states to determine if the individual packet portions were generated from the same packet. If so, they are recombined into a full packet and are forwarded to the destination. If not, an error is detected. The grouping circuitry automatically realigns the data streams to recover synchronization without the need for any feedback to the individual streams to correct the error.

Abstract: An apparatus and method for encapsulating and forwarding packets on a network are disclosed. The network can include a first subnetwork such as a virtual private network connected to a larger public network such as the Internet. An encapsulating header is attached to a packet to be transferred across the public network from a source node on the private network to a destination node on the private network, such that the packet can be transferred across the public network. The encapsulating header includes a value which is derived from the private header on the packet used to transfer the packet along the private network. The value is therefore associated with a source/destination pair within the private network. The value can be derived by performing a hash operation on the private network header. After the public network header containing the value derived from the private network header is attached to the packet, it can be forwarded across the public network.

Abstract: An apparatus and method for monitoring data flow at a node on a network are disclosed. A memory location or “bucket” is allocated to each of a plurality of links and classes of service at the node. A free-running counter is incremented at a rate determined by the maximum allowable data rates on the various links and classes of service. When a data packet is received at a particular link and class of service, the corresponding memory location or bucket is adjusted or “leaked” by subtracting the present counter value from the present bucket contents. That difference is then added to the number of units of data, i.e., bytes or groups of bytes of data, contained in the incoming packet. That sum is then compared with a predetermined threshold determined by the allowable data rate associated with the link and class of service. If the threshold is exceeded, then the incoming data packet is marked accordingly.

Abstract: A method for routing a packet received in a packet router is taught, the method comprising the steps of selecting a logical interface having multiple physical ports as a destination for the packet, processing any one or more addresses or labels of the packet and other packets received by a common function, producing thereby results unique to the packets in which the addresses and labels processed differ, (c) mapping the physical ports at the destination to the unique results produced by processing the addresses or labels of packets, and (d) routing the data packet according to the mapping. Weighting is applied to physical ports in the mapping, the weighting reflecting different transmission capacities of the ports. Apparatus for practicing the invention is taught as well.

Abstract: An apparatus and method for queuing data such as data being transferred across or within a switching node on a network are described. The queuing apparatus includes a plurality of inputs for receiving data to be transferred to at least one output, each input being adapted to receive data at a data rate associated with the input. Each input transfers data to a relatively short queue which stores the data received at the input. Each output is associated with as many short queues as their inputs capable of transferring data to the output. A long queue associated with the output receives data from each of the short queues associated with the output and forwards the data to the output. A control circuit associated with the output transfers data stored in all of the short queues associated with the output into the long queue. This transfer takes place at a data rate that is higher than the data rate associated with the input such that the short queues are prevented from becoming full.

Abstract: A modular and adjustable backplane assembly for providing a fiber-optics backplane interface to a plurality of router cards functioning as a data router is provided. The assembly includes a first portion having a first array of connectors for interfacing with a compatible array of second connectors engaging specific ones of the router cards, and a second portion having a second array of connectors for interfacing with a compatible array of second connectors engaging specific others of the router cards. The mechanics of the assembly enable a moveable attachment with respect to the first and second portions such that they may be positionally adjusted during mounting, and wherein external data paths are provided from individual ones of the connectors to individual others of the connectors by fiber-optic conductors.

Abstract: A method for performing an in-service software upgrade to a data router follows steps of (a) providing a source node hosting an upgrade software package; (b) causing an upgrade command to be executed; (c) establishing, as a result of the upgrade command, a network session between the data router and the source node; (d) receiving the upgrade software at the router; (e) copying and distributing, within the router, the upgrade software to designated components slated for upgrade; (f) designating one or more components in the router as backups for each component to be upgraded; (g) backing up services and software running on each target element to be upgraded to designated backup element or elements while upgrade proceeds for the target element; (h) causing a switchover at the target element to the new software; and (i) repeating steps (g) and (h) until all the components slated for upgrade are upgraded.

Abstract: A distributed Link-State Routing Protocol (LSRP) system in a packet switch having external communication ports has a first card executing Update process of the LSRP, making database updates, a second card executing Decision process(Shortest Path First (SPF)) of the LSRP, and a communication fabric coupling the cards with each other and the external ports. The LSRP may be an IS-IS system. In some embodiments there are additional cards involved, and the distribution of Link-State functions is over a set of multiple cards. Also in some embodiments there is a Location Service (LS) controller monitoring and configuring cards in the system.

Abstract: A switching node for transferring packets, each including a destination address, in a network includes a plurality of input port modules, a plurality of output port modules and a switching fabric, including a packet meta-data processor and a packet switch. Each input port module is connected to a communication link for receiving packets thereover, and each output port module is connected to a communication link for transmitting packets thereover. Each input port module, upon receiving a packet, buffers the packet and generates a meta-data packet therefor identifying the output port module that is to transmit the packet and packet identifier information, and provides it to the packet meta-data processor.

Abstract: An apparatus and method for forwarding packets of data across a switching node on a network are disclosed. A packet of data to be forwarded includes a destination address, which can be partitioned into a plurality of subaddress fields. To improve speed of packet forwarding, destination addresses are processed in a pipelined fashion. To that end, the system includes a plurality of pipelined subaddress processors which process a respective plurality of subaddress fields of the destination addresses. Addresses are received during addressing intervals. During a first interval, a first subaddress of a first packet is processed by a first subaddress processor. During a next interval, a second subaddress processor processes a second subaddress field of the first packet destination address while the first subaddress processor processes the first subaddress field of a destination address of a next packet.

Abstract: A line card for a data packet router interfaces to a high-speed standard data link, and has a first portion interfacing to the router and having a plurality of slower ports, and a second portion having a framer compatible with and coupled to the data link. The framer is coupled through an ingress and an egress data path between the framer and the slower ports, each with separate ingress buffers and egress buffers for each port. An interface control circuit controls data packet transfers between the slower ports and the framer in both directions. In a preferred embodiment a function is used by the control circuit to map packets from the link to the ports, using keys extracted from the incoming packets. For an IP packet the key is the source address, destination address (SA/DA) pair, which constrains packets for same IP conversations to be routed by the same path.

Abstract: An apparatus and method for monitoring data flow at a node on a network are disclosed. A memory location or “bucket” is allocated to each of a plurality of links and classes of service at the node. A free-running counter is incremented at a rate determined by the maximum allowable data rates on the various links and classes of service. When a data packet is received at a particular link and class of service, the corresponding memory location or bucket is adjusted or “leaked” by subtracting the present counter value from the present bucket contents. That difference is then added to the number of units of data, i.e., bytes or groups of bytes of data, contained in the incoming packet. That sum is then compared with a predetermined threshold determined by the allowable data rate associated with the link and class of service. If the threshold is exceeded, then the incoming data packet is marked accordingly.

Abstract: A method optimizes performance in a data network including a plurality of ingress ports and output queues. Ingress rates of a plurality of flows are monitored, where each flow includes a sequence of packets passing from an ingress port to an output queue and each flow has a profile related to flow characteristics. Each packet is marked with a marking based on criteria including the ingress flow rate and the flow profile. A drop probability of each packet is adjusted at an output queue according to a value of a drop function taken as a function of a queue size. The drop function is selected according to the marking on the packet. The drop functions are zero for queue sizes less than a lower threshold range and positive for queue sizes greater than the lower threshold range. By selecting drop functions according to ingress flow rate measurements and flow profiles, the data network can be optimized for overall system performance.