diff --git a/docs/tunneling/fastd.md b/docs/tunneling/fastd.md
index b2d0a51..8d1956c 100644
--- a/docs/tunneling/fastd.md
+++ b/docs/tunneling/fastd.md
@@ -47,6 +47,7 @@ peer "<peerName>"
     remote <type> "<ip>" port <port>;
     key "<peer's public key>";
     interface "<interface>";
+	float yes;
 }
 
 ```
@@ -94,6 +95,9 @@ Now we need to fill in the peer details of the node you are connecting to:
 5. `"<peer's public key>"`
 	* Set this to your peer's public key
 
+> The `float yes` is to allow the peer with the provided public key to connect to you using a source address **other** than the one specified (as fastd does authenticate against that). [Read more](https://fastd.readthedocs.io/en/stable/manual/config.html#main-configuration).
+
+
 The last thing to configure now is to rise the interface up when fastd starts (as it normally doesn't rise it for you), all occurences of `<interfaceName>` here should match the one in the `interface <interfaceName>;` declaration as shown earlier.
 
 ### Starting and maintaining the daemon