A random adaptive method to adjust MAC parameters inIEEE802.11e WLAN

来源期刊：中南大学学报(英文版)2009年第4期

论文作者：王建新 李婧

文章页码：629 - 635

Key words：wireless local area networks (WLAN); IEEE 802.11e; QoS; medium access control (MAC)

Abstract: The IEEE 802.11e standard is proposed to provide QoS support in WLAN by providing prioritized differentiation of traffic. Since all the stations in the same priority access category (AC) have the same set of parameters, when the number of stations increases, the probability of different stations in the same AC choosing the same values will increase, which will result in collisions. Random adaptive MAC (medium access control) parameters scheme (RAMPS) is proposed, which uses random adaptive MAC differentiation parameters instead of the static ones used in the 802.11e standard. The performance of RAMPS is compared with that of enhanced distributed coordination access (EDCA) using NS2. The results show that RAMPS can reduce collision rate of the AC and improve the throughput by using adaptive random contention window size and inter-frame spacing values. RAMPS ensures that at any given time, several flows of the same priority have different MAC parameter values. By using the random offset for the inter-frame spacing value and the backoff time, RAMPS can provide intra-AC differentiation. The simulation results show that RAMPS outperforms EDCA in terms of both throughput and end-to-end delay irrespective of the traffic load.

基金信息：the National Natural Science Foundation of China
the Natural Science Foundation of Hunan Province, China
the Specialized Research Fund for the Doctoral Program of Higher Education of China
the Major State Basic Research and Development Program of China
the Program for New Century Excellent Talents in University