Fairness for broadband integrated switch architectures under backpressure mechanisms

The unfairness problem associated with the classical cyclic service mechanism in broadband switches with input and output buffering and backpressure control is explained. Three alternative service or selection mechanisms are proposed and are compared from the point of view of fairness, implementation complexity, and cell loss performance. It is found that one policy offers the best performance in terms of fairness and cell loss rate, at the expense of being the most difficult to implement. Another policy is a promising compromise between performance and implementation complexity and does not exhibit any serious unfairness problems. The performance of these policies is also investigated under two different nonuniform traffic patterns, known to seriously degrade the performance of multistage interconnection networks