Abstract: A method and apparatus for communicating data packets according to classes of service is described. One or more service interfaces are coupled to a plurality of transport interfaces. The service interfaces carry packets having multiple classes of service, while each of the plurality of transport interfaces carries packets of a single class of service. A differentiated services codepoint profile is associated with each service interface and maps a differentiated services codepoint value of a data packet to a class of service and a drop precedence. The data packet is assigned to a transport interface based on its class of service and its drop precedence. Other factors, such as the destination of the data packet may be considered when assigning the data packet to a transport interface. Data packets from different transport interfaces are preferably enqueued in different queues of a destination service interface.

Abstract: A multi-protocol switch that supports both ATM and IP traffic and method for use is presented. The multi-protocol switch associates certain input connections, as identified by virtual path identifier/virtual connection identifier (VPI/VCI), with either IP or ATM traffic. When the connection identifier for a cell received indicates that the cell is an ATM cell, the multi-protocol switch forwards the cell through the switch, where the forwarding is based on the connection identifier for the cell. If the connection identifier for a cell indicates that the cell is IP traffic, the cell is stored with other cells included in the IP packet to which the cells correspond within the ingress line card of the switch. The destination address included in the packet is used to determine a forwarding decision for the cells included in the packet. After at least partial reassembly, the packet is segmented and forwarded through the switch based on the forwarding decision determined from the destination address.

Abstract: A method and apparatus for supporting virtual path aggregations (VPAs) in a communications network is presented. To establish a VPA in the network, a request for the VPA is received, where the request indicates a desired data path between a source switch and a destination switch. Based on the request, it is determined whether or not there are resources available to create the VPA. If the resources are present, the VPA is created. Once created, connections may be established using the VPA by first determining whether or not the needs of the connection are satisfied by the capabilities of the VPA. If the VPA is capable of supporting the connection, the connection is established using the VPA. If the VPA is not capable of supporting the connection, the connection may either be established using other resources or rejected.

Abstract: A method and network element for feedback control for adjusting a rate of message transmission over a connection in a network is provided. The connection comprises a source and destination linked by forward and backward message paths. The source has instructions for setting a message transmission rate for the connection provided by feedback messages received, each containing an explicit rate of transmission. The method comprises steps: receiving feedback messages from the backward path; extracting an explicit rate being carried by each feedback message received; storing each feedback message received in a queue; retrieving a stored feedback message and, substantially when it is transmitted, marking it with an explicit rate determined from an extracted explicit rate pertaining to another message received more recently and a rate determined from a state of congestion of the network element; and externally transmitting the feedback message over the backward message path once so marked.

Abstract: A method and apparatus for communicating data packets according to classes of service is described. One or more service interfaces are coupled to a plurality of transport interfaces. The service interfaces carry packets having multiple classes of service, while each of the plurality of transport interfaces carries packets of a single class of service. A differentiated services codepoint profile is associated with each service interface and maps a differentiated services codepoint value of a data packet to a class of service and a drop precedence. The data packet is assigned to a transport interface based on its class of service and its drop precedence. Other factors, such as the destination of the data packet may be considered when assigning the data packet to a transport interface. Data packets from different transport interfaces are preferably enqueued in different queues of a destination service interface.

Abstract: There is provided a method and device for measuring a rate of message element traffic over a message path in a communications network. The path includes at least one connection and is associated with a maximum rate of transmission. The path is periodically polled for transmission of a message element, the polling being performed at a polling rate associated with polling intervals which are at least as frequent as the maximum rate of transmission. If transmission of a message element is detected during a polling interval, a running count of such detection is incremented, the running count of detection being associated with the connection over which the message element was detected. If transmission of a message element is not detected, a running count of such non-detection is incremented, the running count of non-detection being associated with inactivity of the message path.

Abstract: A calendar based ATM cell scheduling device is used to maintain accurate shaping of cell streams in order to satisfy traffic management guarantees. In certain applications cell insertion may occur downstream of the scheduling device, potentially violating traffic descriptors. The correction means provided by the present invention allows for such downstream cell insertion without violating guarantees by generating a calendar slip in the scheduling device.

Abstract: Data traffic such as cell streams in an ATM communication network frequently contain data destined for multiple output ports having different transmission data rates. In order to accurately schedule such traffic a clocking signal unique to each output data rate is required. This invention provides systems and methods for generating the necessary clock signals utilizing a single timing reference.

Abstract: Data traffic such as cell streams in an ATM communication network frequently contain data destined for multiple output ports having different transmission data rates. In order to accurately schedule such traffic a clocking signal unique to each output data rate is required. This invention provides systems and methods for generating the necessary clock signals utilizing a single timing reference.