1 Analysis of the IEEE 802.11 DCF with Service Differentiation Support in Non-Saturation Conditions

Abstract. Although the performance analysis of the IEEE 802.11 Distributed Coordination Function (DCF) in saturation state has been extensively studied in the literature, little work is present on performance analysis in non-saturation state. In this paper, a simple model is proposed to analyze the performance of IEEE 802.11 DCF with service differentiation support in non-saturation states, which helps to obtain a deeper insight into the IEEE 802.11 DCF. Based on the proposed model, we can approximately evaluate the most important system performance measures, such as packet delays, which provide one with an important tool to predict and optimize the system performance. Moreover, a practical method to meet packet delay requirements is presented based on our theoretical results. Comparisons with simulations show that this method achieves the specified packet delay requirements with good accuracy