Rate equalization: A new approach to fairness in deterministic quality of service

Scheduling protocols that provide both rate and fairness guarantees, such as Weighted Fair Queuing, distribute the unused capacity among the flows in proportion to the reserved rate of the flows. Thus, flows whose reserved rate is the largest will receive a larger share of the unused capacity. We present a scheduling algorithm that first distributes unused capacity to those flows whose reserved rate is the least. This allocation continues until the flows with least reserved rate and the flows with the next-to-least reserved rate are given the same capacity. If enough unused capacity is available, all flows will receive the same capacity, and the scheduler will simply behave like Fair Queuing.