Abstract: This invention provides rate shaping in per-flow output queued routing mechanisms for unspecified bit rate service.

Abstract: A network infrastructure comprises a number of connective devices (routers, repeaters, bridges, etc.) to form a communication network for a plurality of end nodes. Message packets originating with an end node are assigned an input virtual network and workgroup identification at the port at which the packet enters the network. This assigned input virtual network and workgroup identification is compared, at each port from which the packet can exit the network infrastructure, with output virtual network and workgroup identification assigned the particular port. If the input virtual network information does not match the output virtual network information, the packet is prohibited from exiting that port. Even if there is a match between the input and output virtual network information, there must also be a match between at least one bit of the input workgroup identification and the output workgroup identification before the packet can exit the port.

Abstract: Rate shaping is provided in per-flow output queued routing mechanisms having output links servicing multiple physical layers.

Abstract: Rate shaping is provided in per-flow queued routing mechanisms for statistical bit rate service.

Abstract: Rate shaping is provided in per-flow queued routing mechanisms for available bit rate service. A traffic shaper in a packet switched communications system serially emits packets of time multiplexed flows in substantial compliance with individual network traffic contracts for the respective flows. The individual network traffic contracts include contracts which specify respective peak packet emission rates and associated peak rate tolerances for certain of the flows and which cause each of the flows to fall into mutually exclusive categories. The traffic shaper includes a queuing mechanism and a scheduling mechanism. The queuing mechanism organizes pending packets of active flows, including the certain flows, in respective queues in accordance with an oldest pending packet at head of queue order. The scheduling mechanism is coupled to the queuing mechanism for scheduling the packets of the active flows for emission.