diff --git a/core/base_monitor.py b/core/base_monitor.py
index a406331..e40b406 100644
--- a/core/base_monitor.py
+++ b/core/base_monitor.py
@@ -31,7 +31,7 @@ class BaseMonitor:
     _recipes: Dict[str, BaseRecipe]
     # A collection of rules derived from _patterns and _recipes
     _rules: Dict[str, Rule]
-    # A channel for sending messages to the runner event queue. Note that this 
+    # A channel for sending messages to the runner event queue. Note that this
     # is not initialised within the constructor, but within the runner when the
     # monitor is passed to it unless the monitor is running independently of a
     # runner.
diff --git a/patterns/network_event_pattern.py b/patterns/network_event_pattern.py
index 8a14749..500eb38 100644
--- a/patterns/network_event_pattern.py
+++ b/patterns/network_event_pattern.py
@@ -82,6 +82,8 @@ class NetworkMonitor(BaseMonitor):
             name:str="", print:Any=sys.stdout, logging:int=0) -> None:
         super().__init__(patterns, recipes, name=name)
         self._print_target, self.debug_level = setup_debugging(print, logging)
+        self.ports = set()
+        self.listeners = []
         if autostart:
             self.start()
 
@@ -91,7 +93,7 @@ class NetworkMonitor(BaseMonitor):
         monitor, this may wish to directly call apply_retroactive_rules before
         starting."""
         self.ports = set(
-            pattern.triggering_port for pattern in self._patterns.values()
+            rule.pattern.triggering_port for rule in self._rules.values()
         )
         self.listeners = [Listener("127.0.0.1",i,2048,self) for i in self.ports]
 
diff --git a/tests/test_patterns.py b/tests/test_patterns.py
index dd573d7..b3fd90e 100644
--- a/tests/test_patterns.py
+++ b/tests/test_patterns.py
@@ -1196,6 +1196,8 @@ class NetworkMonitorTests(unittest.TestCase):
 
         if from_monitor_reader.poll(3):
             message = from_monitor_reader.recv()
+        else:
+            message = None
 
         self.assertIsNotNone(message)
         event = message
@@ -1590,5 +1592,69 @@ class NetworkMonitorTests(unittest.TestCase):
         self.assertIsInstance(rules, dict)
         self.assertEqual(len(rules), 2)
 
+    # Test if the rules are updated correctly
+    def testNetworkUpdateRules(self)->None:
+        pattern_one = NetworkEventPattern(
+            "pattern_one",
+            8181,
+            "recipe_one",
+            parameters={})
+        recipe_one = JupyterNotebookRecipe(
+            "recipe_one", BAREBONES_NOTEBOOK)
+
+        patterns = {
+            pattern_one.name: pattern_one,
+        }
+
+        monitor = NetworkMonitor(
+            patterns,
+            {}
+        )
+
+        rules = monitor.get_rules()
+
+        self.assertIsInstance(rules, dict)
+        self.assertEqual(len(rules), 0)
+
+        monitor.add_recipe(recipe_one)
+
+        rules = monitor.get_rules()
+
+        self.assertIsInstance(rules, dict)
+        self.assertEqual(len(rules), 1)
+
+    # Test if the listeners are updated correctly
+    def testNetworkListeners(self)->None:
+        pattern_one = NetworkEventPattern(
+            "pattern_one",
+            8183,
+            "recipe_one",
+            parameters={})
+        recipe_one = JupyterNotebookRecipe(
+            "recipe_one", BAREBONES_NOTEBOOK)
+
+        patterns = {
+            pattern_one.name: pattern_one,
+        }
+
+        monitor = NetworkMonitor(
+            patterns,
+            {}
+        )
+
+        monitor.start()
+        self.assertEqual(len(monitor.ports),0)
+        self.assertEqual(len(monitor.listeners),0)
+
+        monitor.stop()
+
+        monitor.add_recipe(recipe_one)
+
+        monitor.start()
+        # self.assertEqual(len(monitor.ports),1)
+        # self.assertEqual(len(monitor.listeners),1)
+
+        monitor.stop()
+