diff --git a/simpleAPI/config/config.php b/simpleAPI/config/config.php
index 619e73e11d..f6a537950d 100644
--- a/simpleAPI/config/config.php
+++ b/simpleAPI/config/config.php
@@ -4,7 +4,7 @@
     // MQTT Broker Konfiguration
     'mqtt' => [
         'server' => 'localhost',
-        'port' => 1884,
+        'port' => 8883,
         'validate_cert' => false,
         'username' => '',
         'password' => '',
@@ -19,7 +19,7 @@
 
     // Authentifizierung
     'auth' => [
-        'enabled' => false,
+        'enabled' => true,
         'require_https' => false,
 
         // Gültige Tokens
diff --git a/simpleAPI/simpleapi.php b/simpleAPI/simpleapi.php
index 1aa678ee0d..8deb63b2b5 100644
--- a/simpleAPI/simpleapi.php
+++ b/simpleAPI/simpleapi.php
@@ -31,8 +31,8 @@ public function __construct()
         // Parameter Handler initialisieren
         $this->parameterHandler = new ParameterHandler($this->mqttClient);
 
-        // Authenticator initialisieren
-        $this->authenticator = new Authenticator($this->config);
+        // Authenticator initialisieren (mit MqttClient für Anmeldedaten-Test)
+        $this->authenticator = new Authenticator($this->config, $this->mqttClient);
     }
 
     /**
@@ -61,6 +61,7 @@ public function handleRequest()
             $params = array_merge($_GET, $_POST);
 
             // Debug-Modus
+            $debugInfo = [];
             if (isset($params['debug']) && $params['debug'] === 'true') {
                 $this->config['debug'] = true;
             }
@@ -75,6 +76,20 @@ public function handleRequest()
                 return;
             }
 
+            // MQTT-Anmeldedaten aus Parametern übernehmen falls vorhanden
+            if (isset($params['username']) && isset($params['password'])) {
+                $this->mqttClient->setCredentials($params['username'], $params['password']);
+                
+                if ($this->config['debug']) {
+                    $debugInfo[] = "Using MQTT credentials from parameters: username={$params['username']}";
+                }
+            } else {
+                // Keine Parameter-Anmeldedaten vorhanden
+                if ($this->config['debug']) {
+                    $debugInfo[] = "No credentials provided via parameters, using config or anonymous access";
+                }
+            }
+
             // Schreibvorgänge prüfen
             $writeParams = $this->getWriteParameters($params);
             if (!empty($writeParams)) {
@@ -96,7 +111,7 @@ public function handleRequest()
             // Lesevorgänge verarbeiten
             $readParams = $this->getReadParameters($params);
             if (!empty($readParams)) {
-                $result = $this->handleReadRequest($readParams, $params);
+                $result = $this->handleReadRequest($readParams, $params, $debugInfo);
 
                 // Raw-Ausgabe Validierung
                 if (isset($params['raw']) && $params['raw'] === 'true') {
@@ -345,9 +360,14 @@ private function handleWriteRequest($writeParams, $allParams)
     /**
      * Leseanfrage verarbeiten
      */
-    private function handleReadRequest($readParams, $allParams)
+    private function handleReadRequest($readParams, $allParams, $debugInfo = [])
     {
         $result = [];
+        
+        // Debug-Informationen hinzufügen wenn vorhanden
+        if (!empty($debugInfo) && $this->config['debug']) {
+            $result['debug_info'] = $debugInfo;
+        }
 
         foreach ($readParams as $param => $id) {
             try {
diff --git a/simpleAPI/src/Authenticator.php b/simpleAPI/src/Authenticator.php
index f0047d6648..a93af05052 100644
--- a/simpleAPI/src/Authenticator.php
+++ b/simpleAPI/src/Authenticator.php
@@ -8,10 +8,12 @@
 class Authenticator
 {
     private $config;
+    private $mqttClient;
 
-    public function __construct($config)
+    public function __construct($config, $mqttClient = null)
     {
         $this->config = $config;
+        $this->mqttClient = $mqttClient;
     }
 
     /**
@@ -39,6 +41,11 @@ public function authenticate($params)
             return true;
         }
 
+        // Fallback: Prüfen ob MQTT Broker ohne Authentifizierung zugänglich ist
+        if ($this->checkMqttNoAuth()) {
+            return true;
+        }
+
         return false;
     }
 
@@ -130,20 +137,27 @@ private function validateCredentials($username, $password)
     {
         $users = $this->config['auth']['users'] ?? [];
 
-        if (!isset($users[$username])) {
-            return false;
+        // Zuerst gegen definierte Benutzer prüfen
+        if (!empty($users) && isset($users[$username])) {
+            $storedPassword = $users[$username];
+
+            // Passwort-Hash prüfen
+            if (strpos($storedPassword, '$') === 0) {
+                // Gehashtes Passwort
+                return password_verify($password, $storedPassword);
+            } else {
+                // Klartext (nicht empfohlen)
+                return hash_equals($storedPassword, $password);
+            }
         }
 
-        $storedPassword = $users[$username];
-
-        // Passwort-Hash prüfen
-        if (strpos($storedPassword, '$') === 0) {
-            // Gehashtes Passwort
-            return password_verify($password, $storedPassword);
-        } else {
-            // Klartext (nicht empfohlen)
-            return hash_equals($storedPassword, $password);
+        // Wenn keine lokalen Benutzer definiert sind oder MqttClient verfügbar ist:
+        // Anmeldedaten gegen MQTT Broker testen
+        if ($this->mqttClient && (empty($users) || !isset($users[$username]))) {
+            return $this->mqttClient->testCredentials($username, $password);
         }
+
+        return false;
     }
 
     /**
@@ -181,4 +195,18 @@ private function isHttps()
             $_SERVER['SERVER_PORT'] == 443 ||
             (isset($_SERVER['HTTP_X_FORWARDED_PROTO']) && $_SERVER['HTTP_X_FORWARDED_PROTO'] === 'https');
     }
+
+    /**
+     * Prüfen ob MQTT Broker ohne Authentifizierung zugänglich ist
+     */
+    private function checkMqttNoAuth()
+    {
+        // Nur wenn MqttClient verfügbar ist
+        if (!$this->mqttClient) {
+            return false;
+        }
+
+        // Test-Verbindung ohne Anmeldedaten
+        return $this->mqttClient->testCredentials('', '');
+    }
 }
diff --git a/simpleAPI/src/MqttClient.php b/simpleAPI/src/MqttClient.php
index 4e2e896042..c45f81cc1b 100644
--- a/simpleAPI/src/MqttClient.php
+++ b/simpleAPI/src/MqttClient.php
@@ -28,6 +28,15 @@ public function __construct($config)
         $this->clientid = $config['mqtt']['clientid'] ?? 'SimpleAPI_' . uniqid();
     }
 
+    /**
+     * MQTT-Anmeldedaten aktualisieren
+     */
+    public function setCredentials($username, $password)
+    {
+        $this->username = $username;
+        $this->password = $password;
+    }
+
     /**
      * Verbindung testen
      */
@@ -41,6 +50,28 @@ public function connect()
         return !preg_match('/error|failed|unable/i', $result ?? '');
     }
 
+    /**
+     * Anmeldedaten am MQTT Broker testen
+     */
+    public function testCredentials($username, $password)
+    {
+        // Test-Verbindung mit mosquitto_sub (sehr kurzes Timeout)
+        $cmd = $this->buildMosquittoCommandWithCredentials('sub', '$SYS/broker/uptime', '', 1, 2, $username, $password);
+        $result = shell_exec($cmd . ' 2>&1');
+        
+        // Prüfen auf Authentifizierungsfehler
+        if (preg_match('/not authorised|connection refused|authentication failed|username or password invalid/i', $result ?? '')) {
+            return false;
+        }
+        
+        // Prüfen auf andere schwerwiegende Fehler
+        if (preg_match('/connection error|network unreachable|no such host/i', $result ?? '')) {
+            return false;
+        }
+        
+        return true;
+    }
+
     /**
      * Wert aus MQTT Topic lesen
      */
@@ -107,6 +138,14 @@ public function setValue($topic, $value)
      * Mosquitto-Kommando erstellen
      */
     private function buildMosquittoCommand($type, $topics, $message = '', $count = null, $timeout = 1, $extraArgs = [])
+    {
+        return $this->buildMosquittoCommandWithCredentials($type, $topics, $message, $count, $timeout, $this->username, $this->password, $extraArgs);
+    }
+
+    /**
+     * Mosquitto-Kommando mit spezifischen Anmeldedaten erstellen
+     */
+    private function buildMosquittoCommandWithCredentials($type, $topics, $message = '', $count = null, $timeout = 1, $username = null, $password = null, $extraArgs = [])
     {
         $binary = $type === 'sub' ? 'mosquitto_sub' : 'mosquitto_pub';
 
@@ -123,11 +162,14 @@ private function buildMosquittoCommand($type, $topics, $message = '', $count = n
         }
 
         // Username/Passwort hinzufügen falls konfiguriert
-        if (!empty($this->username)) {
-            $cmd .= sprintf(" -u %s", escapeshellarg($this->username));
+        $useUsername = $username !== null ? $username : $this->username;
+        $usePassword = $password !== null ? $password : $this->password;
+        
+        if (!empty($useUsername)) {
+            $cmd .= sprintf(" -u %s", escapeshellarg($useUsername));
         }
-        if (!empty($this->password)) {
-            $cmd .= sprintf(" -P %s", escapeshellarg($this->password));
+        if (!empty($usePassword)) {
+            $cmd .= sprintf(" -P %s", escapeshellarg($usePassword));
         }
 
         // Topic(s) hinzufügen