diff --git a/config.example.php b/config.example.php
index e3f60bb..6506b6e 100644
--- a/config.example.php
+++ b/config.example.php
@@ -1,5 +1,5 @@
-<?php 
-$RUNTIME['PDO']	                    =   new PDO('mysql:host=...;dbname=...', '...', '...');
+<?php
+$RUNTIME['PDO']                     =   new PDO('mysql:host=...;dbname=...', '...', '...');
 
 $RUNTIME['GRID']['NAME']            = "OpenSim";
 $RUNTIME['GRID']['MAIN_NEWS']       = "Yet an other OpenSim Grid.";
@@ -24,4 +24,6 @@ $RUNTIME['DOMAIN']                  = "mcp.4creative.net";
 $RUNTIME['IAR']['BASEURL']          = "https://mcp.4creative.net/data/";
 
 $RUNTIME['PASSWORD_MIN_LENGTH']     = 8;
-?>
+
+$RUNTIME['CRON_RESTRICTION'] = 'key';
+$RUNTIME['CRON_KEY'] = 'changeme';
diff --git a/cron.php b/cron.php
new file mode 100644
index 0000000..d01c10f
--- /dev/null
+++ b/cron.php
@@ -0,0 +1,24 @@
+<?php
+$RUNTIME = array();
+$RUNTIME['BASEDIR'] = __DIR__;
+set_include_path('.:'.$RUNTIME['BASEDIR']);
+include_once "config.php";
+
+if(!isset($RUNTIME['CRON_RESTRICTION'])) {
+    http_response_code(500);
+    die();
+}
+
+if ($RUNTIME['CRON_RESTRICTION'] != 'none' && (!isset($RUNTIME['CRON_KEY']) || !isset($REQUEST['key']) || $_REQUEST['key'] !== $RUNTIME['CRON_KEY'])) {
+    http_response_code(401);
+    die();
+}
+
+if ($handle = opendir('./cron/')) {
+    while (false !== ($entry = readdir($handle))) {
+        if ($entry != "." && $entry != "..") {
+            include_once "./cron/".$entry;
+        }
+    }
+    closedir($handle);
+}
diff --git a/crone.php b/crone.php
deleted file mode 100644
index 84a5b5b..0000000
--- a/crone.php
+++ /dev/null
@@ -1,26 +0,0 @@
-<?php
-date_default_timezone_set("Europe/Berlin");
-error_reporting(E_ALL);
-session_start();
-
-$RUNTIME = array();
-$RUNTIME['BASEDIR'] = __DIR__;
-set_include_path('.:'.$RUNTIME['BASEDIR']);
-include_once("app/utils.php");
-include_once("app/HTML.php");
-include_once("config.php");
-
-if ($handle = opendir('./cron/')) 
-{
-	while (false !== ($entry = readdir($handle))) 
-	{
-		if ($entry != "." && $entry != "..") 
-		{
-			include_once "./cron/".$entry;
-		}
-	}
-
-	closedir($handle);
-}
-
-?>
\ No newline at end of file