A Media Stream Track (MST) represents media from an end user. The source can be a physical webcam, microphone, etc. A group of several Media Stream Tracks represent a MediaStream, and are intended to be synchronized when rendered.
The outgoing MST table provides information related to each media source enabled by an end point, and also helps understand whether the end users are exchanging media directly or if there is a bridge between them.
A: Connection end points.
B: Track identifier for each media source (see more info about SSRCs here).
C: Start Time is the time when the media is activated at the sender. When a Sender experiences churn and rejoins a conference, a new Media Stream Track corresponding to the same media type can be initiated by the sender but this will be identified with a new Track ID on a different Start Time.
D: Type of media (Audio or Video) and codecs used.
E: 95% of the values measured are under the value listed here.
Additionally, all the information from webrtc-internals is also available.
1: Select the endpoint that reported statistics to callstats.io.
2: Select outgoing or incoming media traffic, and the MST source (video or audio).