Get MAC Address of a machine in Local LAN network in ASP.Net

Hi! How to get Client MAC address(Web). I used this it's only work in IE. But i want work all browser. How i can solve this?

This script is for IE only:

<script language="javascript" type="text/javascript">

    function showMacAddress() {

        var obj = new ActiveXObject("WbemScripting.SWbemLocator");

        var s = obj.ConnectServer(".");

        var properties = s.ExecQuery("SELECT * FROM Win32_NetworkAdapterConfiguration");

        var e = new Enumerator(properties);

        var output;

        output = '<table border="0" cellPadding="5px" cellSpacing="1px" bgColor="#CCCCCC">';

        output = output + '<tr bgColor="#EAEAEA"><td>Caption</td><td>MACAddress</td></tr>';

        while (!e.atEnd()) {

            e.moveNext();

            var p = e.item();

            if (!p) continue;

            output = output + '<tr bgColor="#FFFFFF">';

            output = output + '<td>' + p.Caption; +'</td>';

            output = output + '<td>' + p.MACAddress + '</td>';

            output = output + '</tr>';

        }

        output = output + '</table>';

        document.getElementById("box").innerHTML = output;

    }

</script>