Eliminating the Performance Anomaly of 802.11b

Abstract. In this paper, we propose a mechanism to eliminate the per-formance anomaly of IEEE 802.11b. Performance anomaly happens when nodes that have different transmission rates are in the same wireless cell. All the nodes in the cell might experience the same throughput even though their transmission rates are different because DCF of WLAN provides equal probability of channel access, but it does not guarantee the equal utilization of the wireless channel among the nodes. To reduce such a performance anomaly, we adjust the frame size proportionally depending on the bit rate. Additionally, our scheme eliminates the per-formance anomaly in multi-hop case. Simulation study shows that our scheme achieves an improvement in the aggregate throughput and the fairness.