# Default elements for routing and antispoofing

Networks that correspond to the IP addresses of each interface are automatically added to the routing and antispoofing configuration.

There is a default Network element called Any network, which is needed to define the default route. You must add a default route for packets whose destination IP address is not included anywhere else in the routing configuration.

On Single Engines, Single IPS engines, and Single Layer 2 Engines, if a dynamic IP address is added to an interface, there is an Automatic Default Route option that is selected by default. This option automatically adds a default route to the routing configuration.

There is also a default Host element for Bootp/DHCP clients in the antispoofing configuration of Engine, Master Engine, and Virtual Engine elements.