On the Cost of Fairness in Ring Networks

The impact of fairness on the throughput of ring networks with spatial reuse is investigated. A model for a slotted ring with spatial reuse that employs a simple fairness mechanism is presented. An exact expression for the expected time taken to evacuate this ring when each node initially contains one packet is derived. The expected evacuation time is used to obtain an exact expression for the throughput of the ring. It is shown that as the number of nodes on the ring increases, the penalty for fairness in terms of throughput becomes negligible. © 1993 IEEE