This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The RTCPeerConnection.oniceconnectionstatechange property is an event handler which specifies a function to be called when the iceconnectionstatechange event is fired on an RTCPeerConnection instance. This happens when the state of the connection's ICE agent, as represented by the iceConnectionState property, changes.


RTCPeerConnection.oniceconnectionstatechange = eventHandler;


This event handler can be set to function which is passed a single input parameter: an Event object describing the iceconnectionstatechange event which occurred. Your code can look at the value of RTCPeerConnection.iceConnectionState to determine what the new state is.


The example below watches the state of the ICE agent for a failure or unexpected closure and takes appropriate action, such as presenting an error message or attempting to restart the ICE agent.

pc.oniceconnectionstatechange = function(event) {
  if (pc.iceConnectionState === "failed" ||
      pc.iceConnectionState === "disconnected" ||
      pc.iceConnectionState === "closed") {
    // Handle the failure

Of course, "disconnected" and "closed" don't necessarily indicate errors; these can be the result of normal ICE negotiation, so be sure to handle these properly (if at all).


Specification Status Comment
WebRTC 1.0: Real-time Communication Between Browsers
The definition of 'RTCPeerConnection.oniceconnectionstatechange' in that specification.
Candidate Recommendation Initial specification.

Browser compatibility

BCD tables only load in the browser

See also