function initKeepAlive(prd) 
	  {
          window.setInterval(sendPing, prd);
      }

	  function sendPing() 
	  {
          var xmlHttp = getXMLHTTP();
          if (xmlHttp)
          {
              xmlHttp.open("GET", "keepAlive.aspx", true);
              xmlHttp.onreadystatechange = function(){}
              xmlHttp.send(null);
          }
      }

	  function getXMLHTTP()
      {
          var xhr = null;
          try 
		  {
              xhr = new ActiveXObject("Msxml2.XMLHTTP");

          } catch(e) 
		  {
              try 
			  {
                  xhr = new ActiveXObject("Microsoft.XMLHTTP");

			  } catch(ee) 
			  {
                  xhr = null;
              }
          }

          if(!xhr && typeof XMLHttpRequest != "undefined") xhr = new XMLHttpRequest();
          return xhr;
      }