Support of multimedia services with the IEEE 802-11 MAC protocol

In order to meet the growing requirement in bandwidth for multimedia services in an IEEE 802.11 wireless local area network, we propose four polling schemes (RR, FIFO, priority, and priority-ELF schemes) combined with the point coordination function (PCF) to improve the utilization of the wireless channel and support certain quality of service (QoS) of multimedia traffic. We introduce the proposed polling schemes, and also evaluate their performance based on simulations. Although both RR and FIFO schemes have better performance than the pure distributed coordination function (DCF) scheme generally, their performances may be affected by some traffic patterns. We also show that the priority and priority-ELF schemes are sufficient to maintain the QoS of multimedia traffic. As errors occur, the priority-ELF scheme achieves higher utilization of the wireless channel