diff --git a/sec/ex-4_iptables.adoc b/sec/ex-4_iptables.adoc
index f995545..26e6d7c 100644
--- a/sec/ex-4_iptables.adoc
+++ b/sec/ex-4_iptables.adoc
@@ -47,7 +47,7 @@ Shorewall is already installed on swarmlab-sec.
 == Basic Two-Interface Firewall
 
 
-basics.png[Basic Two-Interface Firewall]
+image::basics.png[Basic Two-Interface Firewall]