Is there any way to determine if a remote peer is disconnected while using the Cloudflare SFU without a signaling server?

Suppose there are five users (A, B, C, D, E) connected to the SFU. And C, E disconnects. I would like to know would A, B, D knows about the disconnection via peer connection.

One solution would be implementing a signaling server that sends a heartbeat every 5 seconds. If no response is received, the session could be terminated.

However, since the client's peer connection is aware of other connections, I assume it should detect the disconnection.

This is what I have tried to check, but to no avail.

 peerConnection.ontrack = (event: RTCTrackEvent) => {
  const checkTrack = setInterval(() => {
    if (event.track.readyState === "ended") {
      console.log(`Track ${event.track.id} is closed with mid ${event.transceiver.mid}`);
      clearInterval(checkTrack);
    }

    if (event.transceiver.currentDirection === 'stopped' || event.transceiver.currentDirection === 'inactive') {
      console.log(`Transceiver ${event.track.id} is closed with mid ${event.transceiver.mid}`);
      clearInterval(checkTrack);
    }
  }, 500);

  event.track.onended = () => {
    console.log(`${event.transceiver.mid} is ended, ${event.track.id}`);
  };

  event.track.onmute = () => {
    console.log(`${event.transceiver.mid} is muted, ${event.track.id}`);
  };
};

Is there any way to determine if a remote peer is disconnected while using the Cloudflare SFU without a signaling server?

Suppose there are five users (A, B, C, D, E) connected to the SFU. And C, E disconnects. I would like to know would A, B, D knows about the disconnection via peer connection.

One solution would be implementing a signaling server that sends a heartbeat every 5 seconds. If no response is received, the session could be terminated.

However, since the client's peer connection is aware of other connections, I assume it should detect the disconnection.

This is what I have tried to check, but to no avail.

 peerConnection.ontrack = (event: RTCTrackEvent) => {
  const checkTrack = setInterval(() => {
    if (event.track.readyState === "ended") {
      console.log(`Track ${event.track.id} is closed with mid ${event.transceiver.mid}`);
      clearInterval(checkTrack);
    }

    if (event.transceiver.currentDirection === 'stopped' || event.transceiver.currentDirection === 'inactive') {
      console.log(`Transceiver ${event.track.id} is closed with mid ${event.transceiver.mid}`);
      clearInterval(checkTrack);
    }
  }, 500);

  event.track.onended = () => {
    console.log(`${event.transceiver.mid} is ended, ${event.track.id}`);
  };

  event.track.onmute = () => {
    console.log(`${event.transceiver.mid} is muted, ${event.track.id}`);
  };
};

• javascript
• audio
• webrtc
• cloudflare
• rtcpeerconnection

2 Answers 2

This is not specific to Cloudflare Calls at all. Since you PeerConnection terminates at the SFU you no longer "see" what happens with the PeerConnections of the other peers connected to the same room on the SFU. You can look at your own PC in a pure P2P call, but not when using an SFU. The two options to solve this would be:

1. Use a signaling server, which I would assume you need anyway to setup the call.
2. Technically the SFU could send your endpoint some kind of event if it detects that one of the other PeerConnections disconnected. But I'm not sure if any pure SFU without a signaling server supports something like that.

You can use WebRTC’s connectionState and iceConnectionState events on your RTCPeerConnection to reliably identify disconnections. These events would fire when the connection state changes.

peerConnection.onconnectionstatechange = () => {
  console.log("Connection State:", peerConnection.connectionState);

  if (peerConnection.connectionState === "disconnected" || 
      peerConnection.connectionState === "failed" || 
      peerConnection.connectionState === "closed") {
    console.log("Remote peer disconnected!");
    // Handle disconnection logic here
  }
};

peerConnection.oniceconnectionstatechange = () => {
  console.log("ICE Connection State:", peerConnection.iceConnectionState);

  if (peerConnection.iceConnectionState === "disconnected" ||
      peerConnection.iceConnectionState === "failed") {
    console.log("ICE Connection Disconnected!");
    // Handle disconnection logic here
  }
};