WebRTC Handshake Timeout on ServiceNow Screen Pop Trigger

{"error": "ICE_CONNECTION_FAILED", "code": 408, "trace": "wss://api.us.genesyscloud.com/v2/webchat/sessions/..."}

Background

Deploying a Genesys Cloud Digital Channel webhook to ServiceNow via REST API. The payload triggers a screen pop on the agent desktop. Environment is v19.8.0, London region. ServiceNow MID server logs show successful receipt of the initial transcript payload.

Issue

The WebRTC connection for the softphone fails to establish simultaneously with the screen pop. The agent hears a dial tone but the call state remains RINGING indefinitely. The Genesys Cloud Architect flow shows the Create Conversation action succeeded, but the subsequent Transfer to Agent action throws a 408 Timeout. This correlates with the ServiceNow ticket creation latency averaging 1.2s.

Troubleshooting

• Verified SDP exchange in browser dev tools; offer/answer cycle completes but ICE candidates are not gathered.
• Confirmed firewall rules allow ports 50000-60000 UDP/TCP.
• Reduced ServiceNow REST API timeout from 30s to 10s; no change in behavior.
• Tested with a simple Log action instead of ServiceNow call; WebRTC connects successfully.
• Checked Genesys Cloud WebRTC SDK version 2.4.1; no known bugs reported for this version.

If you check the docs, they mention that ICE failures in cross-platform integrations often stem from timing mismatches rather than actual network blocking. The 408 code here is misleading; it usually means the WebRTC handshake timed out waiting for the ServiceNow MID server to complete its internal processing before the Genesys Cloud session expired.

Check the iceTimeout parameter in your WebRTC configuration. The default is often too aggressive for heavy REST payloads. You need to extend this window to allow the MID server to parse the JSON and trigger the screen pop event.

{
 "webRTC": {
 "iceTimeout": 30000,
 "turnServers": [
 {
 "url": "turn:turn.genesyscloud.com:3478",
 "username": "your_turn_user",
 "credential": "your_turn_pass"
 }
 ]
 }
}

Also, verify the MID server’s HTTP response time. If it takes longer than 5 seconds to acknowledge the webhook, the Genesys Cloud side drops the connection. Add a simple logging step in ServiceNow to measure the delta between receipt and screen pop initiation.

I ran a similar load test in ap-southeast-1 where the API throughput was fine, but the WebSocket connections dropped under concurrent stress. The fix was increasing the timeout and ensuring the MID server wasn’t bottlenecked by other background jobs.

Reference: https://support.genesys.com/Article/WebRTC-Timeout-Config-Best-Practices

Try adjusting the timeout first. If the issue persists, check the firewall rules between the MID server and the Genesys Cloud TURN servers. The trace ID in your error log should help pinpoint if it’s a network or application layer timeout.

I’d suggest checking out at the timing between the webhook trigger and the WebRTC session initialization. The suggestion above regarding iceTimeout is correct for network latency, but in a ServiceNow integration, the bottleneck is often the MID server processing time before the client even attempts the handshake. If the agent desktop screen pop takes too long to render, the Genesys session may already be in a stale state by the time the browser tries to connect.

When handling legal discovery or high-compliance environments, we often see this exact pattern where the audit trail shows a successful webhook, but the recording export job later fails because the media stream never established. This creates a gap in the chain of custody for the digital interaction.

To mitigate this risk, adjust the sequence:

1. Increase the sessionTimeout in the Webchat widget configuration to at least 120 seconds. This gives the ServiceNow MID server enough time to process the payload and push the screen pop.
2. Implement a pre-check in your ServiceNow script. Before triggering the WebRTC connection, ensure the Genesys session ID is still active using the GET /api/v2/conversations/webchat/{conversationId} endpoint.
3. If the session is inactive, trigger a fallback to standard webchat rather than forcing a WebRTC connection that will fail with ICE errors.

This approach ensures that the recording metadata remains consistent. For legal hold purposes, it is critical that the recording export job can link the initial contact metadata to a valid media file. If the handshake fails silently, the bulk export will include the metadata but no audio, which can cause issues during compliance reviews. Always verify the recordingId is populated in the final payload before considering the interaction complete.