Works even if the TURN server credentials are wrong

The following code logs the offer text but shouldn’t it give an error because the turn server doesn’t exist? Is there a fallback server which the app connects to if the turn server is not found?

const wrtc = require('wrtc');
const Peer = require('simple-peer');

const turnServer = {
    urls: 'turn:fake.address:3478',
    username: 'u',
    credential: 'c'
}
const peer1 = new Peer({ 
    initiator: true, 
    wrtc: wrtc, 
    config: { iceServers: [ turnServer ] }
})

peer1.on('signal', function (data) {
    console.log(JSON.stringify(data));
})

[t-mullen]

The offer is generated client side. The client takes the information you give it and puts it into a format (SDP) to send over the signalling channel. It doesn’t connect to any servers during this process*.

Once signalling is complete, the peers will connect directly if they are on the same local network, try to use STUN if they’re not, and then use TURN if STUN fails. So if your TURN server doesn’t exist and STUN works, the peers will never even notice. Likewise, a bad STUN server won’t be contacted if the peers are on the same local network or machine.

*Aside from ICE candidate gathering without trickle, but if the server is unreachable, it will just be skipped.

[t-mullen]

The offer should be shorter and generate without an error. You’d get a ice failure during connection, unless I’ve made some mistake about the behaviour iceTransportPolicy: 'relay' .

Yes, normal as in using STUN. You can add your own STUN server. You shouldn’t get an error in that code either.