Update README.md

README.md

@@ -3,3 +3,14 @@
 This queries the API of a Omada controller to get the current status of the Accesspoints and sends the information via the respondd protocol. Thus it can be picked up by `yanic` and other respondd queriers.
 
 ## Overview
+
+```mermaid
+graph TD;
+	A{"*respondd_main*"} -->| | B("*omada_client*")
+    A -->| | C("*respondd_client*")
+	B -->|"RestFul API"| D("omada_controller")
+    C -->|"Subscribe"| E("multicast")
+    C -->|"Send per interval / On multicast request"| F("unicast")
+    G{"yanic"} -->|"Request metrics"| E
+    F -->|"Receive"| G
+```