401 Unauthorized from Google’s public STUN server (stun.l.google.com:19302) during ICE gathering

[Mohamed Shakeek]

Hi,

Platform:    [e.g. Chrome 114 on macOS 12.5]
Library:     [e.g. Native WebRTC / React-Native-WebRTC v1.92.1]
STUN Server: stun:stun.l.google.com:19302

I’m seeing intermittent 401 Unauthorized errors from Google’s public STUN server during ICE gathering. It happens randomly sometimes on one Wi-Fi network it works fine, then on another Wi-Fi or when peers connect via mobile hotspot it immediately fails with a 401.
  
Setup:  
const pc = new RTCPeerConnection({
  iceServers: [
    { urls: "stun:stun.l.google.com:19302" }
  ]
});

But when ICE gathering starts, the STUN binding request returns 401 Unauthorized, and no candidates come back. I’ve confirmed that:

• I’m not sending any username or credential fields.

• No TURN credentials are configured.

• This STUN URL previously worked without authentication.

Reproduction Steps:

1. Create RTCPeerConnection with the above ICE config

2. Call pc.createOffer() → pc.setLocalDescription()

3. In the browser console or packet capture, the STUN request to stun.l.google.com:19302 responds with 401.
   

   const configuration = {

       iceServers: [

         { urls: "stun:stun.l.google.com:19302" },

         { urls: "stun:stun1.l.google.com:19302" },

   
   

         // Other public STUNs

         { urls: "stun:stun.ekiga.net" },

         { urls: "stun:stun.sipgate.net" },

       ],

     };

   
   

Expected:
A normal Binding Success Response (no authentication challenge), and ICE candidates populated.  

Actual:
STUN_BINDING_ERROR, 401 Unauthorized challenge, ICE gathering stalls.  

Questions for the community / Google team:

1. Has Google recently enabled authentication on its public STUN endpoint?

2. If so, what credentials (username/password or token) should clients use?

3. If not, is this a temporary outage or misconfiguration?

4. Are there any alternative Google-hosted STUN endpoints we can use in the meantime?