Improving performance through optimization of the RTS/CTS mechanism in IEEE 802.11 Wireless LANs

IEEE 802.11 Medium Access Control (MAC) protocol employs two techniques for packet transmission; the basic access scheme and the RTS/CTS reservation scheme. In this paper, we carry out an analysis in order to derive an all-purpose expression for the threshold value, which determines when the RTS/CTS scheme should be employed, under ideal channel conditions without the presence of hidden stations or transmission errors. The main advantage of our proposed approach is that it is simple and gives insights of the RTS/CTS mechanism. Results based on the presented analysis for the IEEE 802.11b transmission rates and delays study the effect of the different protocol parameters on the RTS/CTS threshold. Moreover, results indicate that proper selection of protocol parameters such as retry limit and physical packet overhead for the specific data rate is of great importance in minimizing packet delay and improving overall performance.