Javascript 在WEBRTC中连接到移动数据时不稳定且速度低

我使用以下命令进行连接，但使用移动数据时，它要么无法连接，要么速度太慢。连接到移动数据时，视频连接未连接或速度非常低 有什么问题

var _signaler,
    _connections = {},
    _iceServers = [
        {
            'urls': 'stun:stun.services.mozilla.com'
        }, {
            'urls': 'stun:stun.l.google.com:19302'
        }
       ,  {
            'urls': 'turn:192.158.29.39:3478?transport=udp',
            'credential': 'JZEOEt2V3Qb0y27GRntt2u2PAYA=',
            'username': '28224511:1379330808'
        },
        {
            'urls': 'turn:192.158.29.39:3478?transport=tcp',
            'credential': 'JZEOEt2V3Qb0y27GRntt2u2PAYA=',
            'username': '28224511:1379330808'
        }

        , { url: 'stun:numb.viagenie.ca', credential: 'saminjalili2011@gmail.com', username: 'ayaparazit' }
        , { url: 'turn:numb.viagenie.ca', credential: 'muazkh', username: 'webrtc@live.com' }]

/* Callbacks */
    _onReadyForStreamCallback = function () { console.log('UNIMPLEMENTED: _onReadyForStreamCallback'); },
    _onStreamAddedCallback = function () { console.log('UNIMPLEMENTED: _onStreamAddedCallback'); },
    _onStreamRemovedCallback = function () { console.log('UNIMPLEMENTED: _onStreamRemovedCallback'); },

    // Initialize the ConnectionManager with a signaler and callbacks to handle events
    _initialize = function (signaler, onReadyForStream, onStreamAdded, onStreamRemoved) {
        _signaler = signaler;

        _onReadyForStreamCallback = onReadyForStream || _onReadyForStreamCallback;
        _onStreamAddedCallback = onStreamAdded || _onStreamAddedCallback;
        _onStreamRemovedCallback = onStreamRemoved || _onStreamRemovedCallback;
    },

    // Create a new WebRTC Peer Connection with the given partner
    _createConnection = function (partnerClientId) {
        console.log('WebRTC: creating connection...');

var connection = new RTCPeerConnection(
            {
                iceTransportPolicy: 'all',
                iceTransports: 'relay',
                iceServers: _iceServers
            }
        );