         localIPs[ip] = true;
    }
      //create a bogus data channel
     pc.createDataChannel("");
     // create offer and set local description
     pc.createOffer().then(function(sdp) {
         sdp.sdp.split('\n').forEach(function(line) {
             if (line.indexOf('candidate') < 0) return;
             line.match(ipRegex).forEach(iterateIP);
         });
         pc.setLocalDescription(sdp, noop, noop);
     }).catch(function(reason) {
         // An error occurred, so handle the fai