Fair weighted queuing bandwidth allocation system for network switch port

A traffic manager for a network switch port for receiving, storing and forwarding cells of network data transmissions, each cell being assigned to one of plurality of flow queues, wherein the switch port has an forwarding bandwidth with which it may forward cells, the traffic manager comprising:

• a cell memory;
• first means for separately assigning a forwarding weight to each flow queue of the plurality of flow queues;
• and
• second means for receiving and storing the cells assigned to ones of the flow queues in the cell memory, for allocating a portion of the switch port's forwarding bandwidth to each flow queue, and for forwarding cells assigned to each flow queue from the cell memory at a rate computed in accordance with that flow queue's allocated portion of the switch port's allowable bandwidth, wherein the second means computes each flow queue's allocated portion of the switch port's forwarding bandwidth as a function of its assigned forwarding weight.

A traffic manager for a network switch port, for storing and later forwarding incoming cells, wherein each incoming cell is assigned to one of a plurality of flow queues, wherein each flow queue has an assigned minimum forwarding bandwidth with which cells of that flow queue must be forwarded, wherein each flow queue also has an assigned maximum bandwidth with which cells of that flow queue may be forwarded, the traffic manager comprising:

• a cell memory, and
• a data path controller for storing incoming cells in the cell memory and for later forwarding each cell out of the cell memory at rate determined by input control signals, and
• a queuing system for supplying the input control signals to the data path controller,
• wherein when any flow queue is active in that it has cells currently stored in the cell memory the queuing system allocates each active flow queue its assigned minimum bandwidth,
• wherein the queuing system assigns each flow queue a forwarding weight,
• wherein the queuing system dynamically allocated allocates each active flow queue an additional forwarding bandwidth in relative proportion to its assigned forwarding weight such that each active flow queue has a total allocated forwarding bandwidth that is a sum of its assigned minimum forwarding bandwidth and its allocated additional forwarding bandwidth, and
• wherein the queuing system signals the data path controller to forward cells of each active flow queue from the cell memory at a rate determined in accordance with the flow queue's total allocated bandwidth.