An analytic model for enhancing IEEE 802.11 point coordination function media access control protocol

The design of media access control (MAC) protocol that can efficiently support the real-time applications in Wireless Local Area Networks (WLANs) is a challenging task, it requires that the MAC layer provide strict delay guarantees for sensitive traffic, the Point Coordination Function (PCF) with Round Robin (RR) polling scheme has been included in IEEE 802.11 MAC protocol to achieve this objective. However, the RR scheme seems difficult to guarantee QoS and satisfy the low delay of the sensitive traffic, yet it can hardly differentiate from priority service for the key station. Thus we utilize an analytic model with two-level-polling mechanism to enhance the RR scheme, and the comparison results show us that the efficiency as well as impartiality of proposed scheme is better than that of the RR scheme. Copyright © 2011 John Wiley & Sons, Ltd.