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WebRTC Metrics

A comprehensive overview of WebRTC statistics, derived calculations, extracted features, and observable signals, to better understand call quality, connectivity, and user experience in rtcStats

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connectionerrorssdpicedebugging

Connection API failures (feature)

SDP and ICE API errors that break a call before media, captured as the error message of the first failed call of each kind.

Description

Connection-level features, extracted per RTCPeerConnection into features_connection.

These features capture the error message of the first failed call of each kind. They are null when the call never failed:

  • addIceCandidateFailure - error message from the first failed addIceCandidate call.
  • setLocalDescriptionFailure - error message from the first failed setLocalDescription call.
  • setRemoteDescriptionFailure - error message from the first failed setRemoteDescription call.

Extracted by the open-source rtcstats-features package into your own database.

Why it matters

These are the failures that kill a call before any media flows. A rejected setRemoteDescription means the two ends could not agree on SDP: a codec mismatch, a malformed offer, or an SDP munging bug in your own code. An addIceCandidate failure means candidates arrived that the peerconnection could not use, often a signaling ordering problem. Because the error string is preserved, you can group failures by message and see whether one class of bug dominates. That turns a vague "some calls do not connect" into a ranked list of concrete SDP and ICE errors to fix.

SQL example

Rank connections by failure type and the specific error string:

SELECT
  connection.set_remote_description_failure AS error_message,
  COUNT(*) AS occurrences
FROM features_connection AS connection
WHERE connection.set_remote_description_failure IS NOT NULL
GROUP BY connection.set_remote_description_failure
ORDER BY occurrences DESC;

Related features

  • Offer/answer timing - how long the same setLocalDescription and setRemoteDescription calls took when they did succeed.

See also