Virtual reservation scheme for supporting CBR multimedia services with strict QoS performance over WLAN and wireless mesh

Carrier sense multiple access and its variants have been widely used in mobile ad hoc networks. However, most existing access mechanisms cannot guarantee quality of service for real-time traffic. In this paper, we present a novel approach to guarantee the performance of real-time applications such as voice and video that require periodic access to the wireless local area network (WLAN) channel. Our approach can work either with distributed coordination function or enhanced distributed coordination function, and includes distributed reservations of time slots between the stations sharing the WLAN without the need to send any signaling or control messages. Stations can access the wireless medium only if they are able to complete the frame transmission without interruption to the reserved slots of existing real-time sessions. Simulation results indicate that the proposed mechanism provides high channel utilization, and bounded delays and jitter for real-time traffic. Copyright (C) 2009 John Wiley & Sons, Ltd.