ip_address.js

<script>
  function matchIP(ipaddress) {
    // Comment following three lines if you want to use the IP range method
    if (ipaddress == "111.222.333.444") {
      dataLayer.push({"internal": "true"});
    }

    // To use the following IP range check, comment the previous three lines
    // of code and uncomment the following lines
    //
    //  var ipRange = ipaddress.split(".");
    //  var lastOctet = parseInt(ipRange.pop());
    //  if(lastOctet >= 1 && lastOctet <= 100) {
    //    dataLayer.push({"internal": "true"});
    //  }
  }
  
  var ipaddress = "";
  try {
    jQuery.ajax({
      type : "GET",
      dataType : "json",
      url : "http://api.hostip.info/get_json.php",
      async : true,
      success : function(data) {
        ipaddress = data.ip;      
      },error : function(errorData) {
        ipaddress = "none";
      },complete : function() {
        matchIP(ipaddress);
      }
    });
  } catch(e) {
    console.log("Oops, something went wrong: " + e.message);
  }
  dataLayer.push({"event": "ipComplete"});
</script>