Planet YouTube: Global, measurement-based performance analysis of viewer;´s experience watching user generated videos

User experience is a very important aspect of user generated video streaming service such as YouTube. In this paper, we perform a global study of user experience for YouTube videos using PlanetLab nodes from all over the world. We analyze the number of pauses, accumulative pause time, rate at which videos were downloaded to clients, and how the YouTube infrastructure impact the viewer´s experience. The data for this analysis was generated by an automated tool from the traces captured during the PlanetLab-based measurement. Results from this analysis show that on average there are about 2.5 pauses per video. Interestingly, we found that on average 25% of the videos with pauses have an accumulative pause time greater than 15 seconds. This shows that not only the number of pauses but also the total length of pauses has to be analyzed to investigate the user experience of watching videos offered by YouTube. In addition, our results show that there is an inverse relationship between the download rates of the videos and the number of pauses encountered.