you can visit the page using
http://username:password@yourhostURL
or you can use "Microsoft.XMLHTTP" object,
var xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
xmlhttp.open("GET","yourHostURL",false,username,password);
xmlhttp.send();
if you are accessing the page from a different domain, you should use "MSXML2.ServerXMLHTTP" object instead of "Microsoft.XMLHTTP"