Voice and video transmissions with global data parameter control for the IEEE 802.11e enhance distributed channel access

Best-effort data control and admission control are vital to guarantee quality of service for real-time ( voice and video) transmissions in the IEEE 802.11e wireless LANs. In this paper, we propose and study a global data parameter control scheme integrated with a measurement-based admission control scheme for the IEEE 802.11e enhanced distributed channel access. In the proposed global data control scheme, the access point dynamically controls best-effort data parameters of stations globally based on traffic condition. Such a global/centralized data parameter control mechanism provides the best fairness for data transmissions among stations. In the proposed centrally-assisted distributed admission control scheme for voice and video transmissions, stations listen to available budgets from the access point to make decisions on acceptance or rejection of a voice or video stream. Such a scheme provides good differentiation among different access categories and provides good fairness among real-time streams within the same access category. The proposed mechanisms are evaluated via extensive simulations. Studies show that, with the proposed global data control scheme and the admission control scheme, quality of service can be greatly improved while maintaining a good utilization.