Video Frame Differentiation for Streamed Multimedia over Heavily Loaded IEEE 802.11e WLAN using TXOP

In this paper we perform an experimental investigation of using video frame differentiation in conjunction with the TXOP facility to enhance the transmission of parallel multimedia streaming sessions in IEEE 802.11e. The delay constraints associated with the audio and video streams that comprise a multimedia session pose the greatest challenge since real-time multimedia is particularly sensitive to delay as the packets require a strict bounded end-to-end delay. Video streaming applications are considered to be bursty. This burstiness is due to the frame rate of video, the intrinsic hierarchical structure of the constituent video frame types, and the different compression ratios for the different video frame types. The TXOP facility is particularly suited to efficiently deal with this burstiness since it can be used to reserve bandwidth for the duration of the packet burst associated with a packetised video frame. Through experimental investigation, we show that there is a significant performance improvement for video streaming applications under heavily loaded conditions by differentiating between the constituent video frame types. The results show that video frame differentiation reduces the mean loss rate by 12% and increases the mean PSNRby 13.1dB.