{| width="40%" align="right" cellpadding="10"|- valign="top"|Command|Description|- valign="top"|'''iptables -P INPUT DROP'''<br>|Set default policy to drop all incoming connections for ALL protocols, ALL communication ports, ALL IP addresses|- valign="top"|'''iptables -P OUTPUT DROP''' | Set default policy to drop all outgoing connections for ALL protocols, ALL communication ports, ALL IP addresses |}