diff --git a/ground-station.py b/ground-station.py
index e218ea7..04c3f1c 100644
--- a/ground-station.py
+++ b/ground-station.py
@@ -2,8 +2,10 @@
 
 import asyncio
 from websockets.server import serve
+from datetime import datetime
 
 ADMIN_ID = "1234"
+BOAT_DATA_INTERVAL_MAX = 0.1 # seconds
 
 BOAT_STATE_INCTRL = 2
 BOAT_STATE_AVAILABLE = 1
@@ -113,7 +115,9 @@ async def on_message(message, client):
                 print("WARN: controll cmd (" + client['id'] + ") to None: " + data[2])
             else:
                 print("INFO: controll cmd (" + client['id'] + ") to " + client['boat']['name'] + ": " + data[2])
-                await client['boat']['ws'].send("d:" + data[2] + "\n")
+                if client['boat']['lastMsg'] + BOAT_DATA_INTERVAL_MAX < datetime.timestamp(datetime.now()):
+                    await client['boat']['ws'].send("d:" + data[2] + "\n")
+                    client['boat']['lastMsg'] = datetime.timestamp(datetime.now())
         else:
             print("WARN: invalid command (" + client['id'] + "): '" + data[1] + "'")
 
@@ -133,7 +137,7 @@ async def new_client(clientId, ws):
 
 async def new_boat(boatId, name, ws):
     """handler for every new boat connection"""
-    boat = { "id": boatId, "name": name, "ws": ws, "state": BOAT_STATE_AVAILABLE }
+    boat = { "id": boatId, "name": name, "ws": ws, "state": BOAT_STATE_AVAILABLE, "lastMsg": 0 }
     print("new boat connected: " + boatId)
     for bo in Boats:
         if bo['id'] == boat['id']: