Abstract: A method of modeling or constructing a switch element uses an ingress stage with input sorters and input routers; an egress stage with output routers and output sorters; and a center stage interconnecting the ingress and egress stages. Routers are partitioned such that each partition is assigned to only one data line. A switch controller and method may use such modeling to advantage. For example, during initial configuration of the switch element, a subset of connections are excluded from a control algorithm that initially configures the switch with the subset being subjected to post processing. Furthermore, a fast rearrangement of the switch rearranges only part of the existing connections and then adds/deletes cross connects as necessary to complete the connections.

Abstract: A switch is provided that includes three stages. The first stages has a plurality of switch circuits. The second stage has a plurality of switch circuits equal to N, where N is any integer other than a power of 2 and where the switch circuits can be logically configured into a logical configuration of a power of 2. The third stages includes a plurality of switch circuits.

Abstract: A method and apparatus for efficiently transporting DS-X traffic in packet form over an ATM or other packet network. Specifically, virtual connection or slot provisioning and/or cell concentration techniques are used to compact the amount of DS-X traffic broadcast between communications system devices such as the access mux and the communications switch and spare bandwidth. In provisioning, a configured DS-X loading of an end node supporting DS-X traffic is ascertained. In turn, a minimum number of virtual connections for bearing packetized DS-X traffic are established, either at communications system configuration or as needed. In concentration processing, a dynamic association between the virtual connections and the DS-X traffic is established, typically on a per frame basis. Only those digital channels entering the node within a given time frame which actually bear DS-X traffic will be assigned a slot within packet. Concentration may be augmented by provisioning to further reduce bandwidth requirements.

Abstract: Fairness is provided among network sessions contending for available bit rate (ABR) service in an asynchronous transfer mode network by determining congestion information on a per port basis. ABR cells are monitored to determine which rate information per outgoing port based on ABR cells leaving a switch. Using the ABR per port rate, the available capacity, and the input rate to output queues, a link congestion parameter (LCP) is determined. Resource Management (RM) cells traveling through the switch are monitored to determine whether the new LCP is lower than the explicit rate (ER) field in RM cell. If the new LCP is lower, the new LCP is stuffed into the RM cell. When the sender receives the LCP value, the sender output rate is adjusted based on the LCP. Because LCP is determined based on per port traffic flow, fairness is provided among session competing for available ABR capacity.

Abstract: A method and apparatus for efficiently transporting DS-X traffic in packet form over an ATM or other packet network. Specifically, virtual connection or slot provisioning and/or cell concentration techniques are used to compact the amount of DS-X traffic broadcast between communications system devices such as the access mux and the communications switch and spare bandwidth. In provisioning, a configured DS-X loading of an end node supporting DS-X traffic is ascertained. In turn, a minimum number of virtual connections for bearing packetized DS-X traffic are established, either at communications system configuration or as needed. In concentration processing, a dynamic association between the virtual connections and the DS-X traffic is established, typically on a per frame basis. Only those digital channels entering the node within a given time frame which actually bear DS-X traffic will be assigned a slot within packet. Concentration may be augmented by provisioning to further reduce bandwidth requirements.

Abstract: A method and apparatus for efficiently transporting DS-X traffic in packet form over an ATM or other packet network. Specifically, virtual connection or slot provisioning and/or cell concentration techniques are used to compact the amount of DS-X traffic broadcast between communications system devices such as the access mux and the communications switch and spare bandwidth. In provisioning, a configured DS-X loading of an end node supporting DS-X traffic is ascertained. In turn, a minimum number of virtual connections for bearing packetized DS-X traffic are established, either at communications system configuration or as needed. In concentration processing, a dynamic association between the virtual connections and the DS-X traffic is established, typically on a per frame basis. Only those digital channels entering the node within a given time frame which actually bear DS-X traffic will be assigned a slot within packet. Concentration may be augmented by provisioning to further reduce bandwidth requirements.

Abstract: The present invention utilizes a combination of time division and space switching to logically create 2n center stage switching circuits in a switch reconfigurable based on the Looping Algorithm, even though the switch includes a non-power of 2 number of center stage physical switches.

Abstract: The benefits of Transport Control Protocol (TCP) over Available Bit Rate (ABR) Service of an Asynchronous Transfer Mode (ATM) network is extended to the entire TCP connection by intercepting and modifying TCP congestion control information in accordance with resource information associated with the TCP connection. An algorithm calculates a new advertised window size based on various network resource parameters, such as ABR. The advertised window is adjusted if the newly calculated window size is smaller than the advertised window size. By adjusting the TCP window, the normal extreme fluctuations of the TCP window are avoided.

Abstract: A switch is provided that includes three stages. The first stages has a plurality of switch circuits. The second stage has a plurality of switch circuits equal to N, where N is any integer other than a power of 2 and where the switch circuits can be logically configured into a logical configuration of a power of 2. The third stages includes a plurality of switch circuits.

Abstract: Methods and apparatus for accelerating a router in a communications network are described. In one embodiment, a router accelerator includes a forwarding table for associatively storing a destination address and a next hop address. If a destination address of a packet matches a destination address in the forwarding table, then logic forwards the packet to a next hop. A router may be coupled to at least one network port through the router accelerator. In another approach, the network includes at least one host and at least one router. The host has at least one routing table for associatively storing a second-level destination address, a second-level next hop address and a first-level next hop address. A router accelerator includes redirect logic for storing the second-level destination address in a second-level next hop address entry in the at least one host routing table. This causes the host to request a first-level next hop address corresponding to the second-level destination address.

Abstract: A plurality of voice-over-ATM modules operate in parallel and each processes at least one type of AAL. Interface circuitry and contention circuitry allow the parallel modules to interact. The result is an interworking between ATM streams and different types of equipment.