Enhancing Over-the-Top Video Streaming Quality with DASH Assisting Network Elements

Abstract

Dynamic Adaptive Streaming over HTTP (DASH) is the leading technology for delivering online video streaming content. However, DASH has performance problems on shared network links. This thesis investigates how DASH Assisting Network Elements (DANEs) can be used to optimize bottleneck links for DASH video traffic, with the goal to improve the viewers' Quality of Experience. DANEs are aware of active DASH players and divide the network bandwidth among the players and other traffic. In the first three years of the PhD, contributions have been made in the areas of multimedia systems and performance modeling: Two prototype implementations of DANEs have been developed and evaluated in both wired and Wi-Fi networks. Experiments with real DASH players show that DANEs significantly increase the video bitrate and reduce the number of changes in video quality. In addition, Markov models have been created to find out how network bandwidth should be divided, and what the effect of bandwidth sharing policies is on the resulting streaming performance. The model was thoroughly evaluated and has shown to be highly accurate. As such, it is a useful tool that can be used to configure and optimize bandwidth sharing in DANEs. In the remaining year of the PhD program, I would like to expand DANE technology and apply it to different use cases such as mobile networks.