diff --git a/agent-node/VERSION b/agent-node/VERSION
index be5b4c7..6f18242 100644
--- a/agent-node/VERSION
+++ b/agent-node/VERSION
@@ -1 +1 @@
-1.1.20
+1.1.21
diff --git a/agent-node/src/agent_node/node.py b/agent-node/src/agent_node/node.py
index d5af6c1..9eb8ba0 100644
--- a/agent-node/src/agent_node/node.py
+++ b/agent-node/src/agent_node/node.py
@@ -125,6 +125,8 @@
             raise RuntimeError("Handshake failed, node cannot start.")
         
         while not self._stop_event.is_set():
+            if not self.transport.is_connected():
+                raise RuntimeError("Transport disconnected.")
             time.sleep(1)
 
     def _handle_cancel(self, cancel_req):