diff --git a/monkey/infection_monkey/tcp_relay.py b/monkey/infection_monkey/tcp_relay.py
index 9fa4be1b6..243204b76 100644
--- a/monkey/infection_monkey/tcp_relay.py
+++ b/monkey/infection_monkey/tcp_relay.py
@@ -6,6 +6,7 @@ from typing import List
 from infection_monkey.transport.tcp import TcpProxy
 
 DEFAULT_NEW_CLIENT_TIMEOUT = 3  # Wait up to 3 seconds for potential new clients to connect
+RELAY_CONTROL_MESSAGE = b"infection-monkey-relay-control-message: -"
 
 
 @dataclass
@@ -77,7 +78,7 @@ class TCPRelay(Thread):
             self._potential_users.append(RelayUser(user, time()))
 
     def on_user_data_received(self, data: bytes, user: str) -> bool:
-        if data.startswith(b"-"):
+        if data.startswith(RELAY_CONTROL_MESSAGE):
             self._disconnect_user(user)
             return False
         return True
diff --git a/monkey/tests/unit_tests/infection_monkey/test_tcp_relay.py b/monkey/tests/unit_tests/infection_monkey/test_tcp_relay.py
index 48dcce2a6..02c577797 100644
--- a/monkey/tests/unit_tests/infection_monkey/test_tcp_relay.py
+++ b/monkey/tests/unit_tests/infection_monkey/test_tcp_relay.py
@@ -1,6 +1,6 @@
 from threading import Thread
 
-from monkey.infection_monkey.tcp_relay import TCPRelay
+from monkey.infection_monkey.tcp_relay import RELAY_CONTROL_MESSAGE, TCPRelay
 
 
 def join_or_kill_thread(thread: Thread, timeout: float):
@@ -46,7 +46,7 @@ def test_user_removed_on_request():
     relay = TCPRelay(9975, "0.0.0.0", 9976)
     new_user = "0.0.0.1"
     relay.on_user_connected(new_user)
-    relay.on_user_data_received(b"-", "0.0.0.1")
+    relay.on_user_data_received(RELAY_CONTROL_MESSAGE, "0.0.0.1")
 
     users = relay.relay_users()
     assert len(users) == 0