urls！ urls！ urls！

  var peerConfig = {
            iceServers: [
                { urls: 'turn:www.2edge.cn:3874','username': 'jiexun', 'credential': 'jiexun' },
                {urls:'stun:stun01.sipphone.com'},
                {urls:'stun:stun.ekiga.net'},
                {urls:'stun:stun.fwdnet.net'},
                {urls:'stun:stun.ideasip.com'},
                {urls:'stun:stun.iptel.org'},
                {urls:'stun:stun.rixtelecom.se'},
                {urls:'stun:stun.schlund.de'},
                {urls:'stun:stun.l.google.com:19302'},
                {urls:'stun:stun1.l.google.com:19302'},
                {urls:'stun:stun2.l.google.com:19302'},
                {urls:'stun:stun3.l.google.com:19302'},
                {urls:'stun:stun4.l.google.com:19302'},
                {urls:'stun:stunserver.org'},
                {urls:'stun:stun.softjoys.com'},
                {urls:'stun:stun.voiparound.com'},
                {urls:'stun:stun.voipbuster.com'},
                {urls:'stun:stun.voipstunt.com'},
                {urls:'stun:stun.voxgratia.org'},
                {urls:'stun:stun.xten.com'},
                {
                    urls: 'turn:numb.viagenie.ca',
                    credential: 'muazkh',
                    username: 'webrtc@live.com'
                }
            ],
        };