According to SamsungDForum, the way to get the DUID ("Unique Device Identifier"):
In index.html add:
<object id='pluginNetwork' border=0 classid='clsid:SAMSUNG-INFOLINK-NETWORK'></object>
<object id='pluginObjectNNavi' border=0 classid='clsid:SAMSUNG-INFOLINK-NNAVI'></object>
And somewhere in your Javascriptห
var networkPlugin = document.getElementById('pluginNetwork');
var nnaviPlugin = document.getElementById('pluginObjectNNavi');
var deviceId = nnaviPlugin.GetDUID(networkPlugin.GetHWaddr());
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edit: , @IvanSolntsev , ESN ( ).
edit2: โโ DUID.