diff --git a/NTPClient.h b/NTPClient.h
index 1a0a962..83db87a 100755
--- a/NTPClient.h
+++ b/NTPClient.h
@@ -37,6 +37,11 @@ class NTPClient {
     NTPClient(UDP& udp, IPAddress poolServerIP, long timeOffset);
     NTPClient(UDP& udp, IPAddress poolServerIP, long timeOffset, unsigned long updateInterval);
 
+    /**
+     * Update config by runtime
+     */
+  void config_update(UDP &udp, const char *poolServerName, long timeOffset, unsigned long updateInterval);
+
     /**
      * Set time server name
      *