User-aware DASH over Wi-Fi

Dynamic Adaptive Streaming over HTTP (DASH) is being adopted as a cost effective means for multimedia delivery. User Adaptive Video (UAV) is a new technique that exploits the perceptual limits of the human visual system to modulate a video stream's bit rate based on the viewing conditions, such as viewing distance and ambient illuminance, resulting in significant bandwidth reduction without perceived loss of quality to the user. UAV presents an opportunity to significantly improve the efficiency of DASH by not requesting unnecessarily high bit rate video. Due to the random access nature of the Wi-Fi MAC protocol and the intricate interaction among DASH traffic flows, it is not clear whether UAV will manifest its benefits in Wi-Fi networks. We design UAV-enabled DASH (UDASH) and evaluate its performance in Wi-Fi networks. We show that UDASH in a Wi-Fi network has the benefits of not only improving the video streaming performance such as reducing the rebuffering probability, but also enhancing the performance of cross traffic. We also give the conditions under which the benefits can be achieved. Simulation results confirm that the benefits of UDASH are significant.