Creating a dash.js client interface. var video = document.querySelector('video'); var player = dashjs.MediaPlayer().create(); var url = "https://dash.akamaized.net/akamai/bbb_30fps/bbb_30fps.mpd"; Collect the results during the playback every 8 seconds. The metrics you should collect periodically are: selected bitrate (Mbps), buffer level (second), measured throughput (Mbps), segment download time (second), and segment size (byte). The result collection can be done either through an implemented customized script or by modifying the HTML of the video player (i.e., add a Javascript function). The bufferlevel, throughput and bitrate have been collected by modifying the HTML file and using: var bufferLevel = player.getBufferLength('video'); and etc. Please implement the collection of segment size and download time (HTML). (Suggestion, one way to solve: download time use DASH events, segment size get the HTTP request and find out the content size)