The Packet Filtering panel allows you to configure packet filtering rules. Use packet filtering to control traffic using a particular service, traffic intended for a particular address, or traffic coming from a particular address.
SunScreen uses ordered packet filtering. The screen assumes that the first rule that matches a packet is the rule that governs the disposition of the packet.
If the packet does not match any rule, the screen uses its default action to determine the disposition of the packet. Typically, the default action logs the packet and drops it, though other options are available.