diff --git a/swarm/networking.md b/swarm/networking.md
index a99eb08d3d..c61d297f3a 100644
--- a/swarm/networking.md
+++ b/swarm/networking.md
@@ -99,6 +99,9 @@ NETWORK ID          NAME                   DRIVER
 5262bbfe5616        node-1/bridge2         bridge
 ```
 
+`--opt encrypted` is a feature only available in Docker Swarm mode. It's not supported in Swarm standalone.
+Network encryption requires key management, which is outside the scope of Swarm.
+
 ## Remove a network
 
 To remove a network you can use its ID or its name. If two different networks