Periods Scheduling Under the HCCA Mode of IEEE 802.11e

To provide strong and reliable support for voice (VO) and video (VI) traffic in IEEE 802.11e networks, a novel scheme called multiple periods scheduling (MPS) is proposed in this paper. Because the original HCCA mode does not support VI traffic properly, a special treatment for VI traffic is introduced by MPS. According to the requirements of both VO and VI traffic, the service period for each stream is assigned by MPS individually. With the aforementioned enhancement, MPS is able to increase the number of accepted traffic streams while keeping delay and jitter at acceptable levels. To analytically demonstrate the merit of the newly proposed scheme, the optimality of MPS is proven first. Then, the optimal values of service periods are provided theoretically. Finally, we show that significant performance improvement over the related schemes in the literature can be achieved by MPS.