Firewall Management Guide

The Common tab holds the rules every network card uses: what you add, remove or turn off there applies to all cards. Virtual interfaces with rules of their own, such as a VPN, do not take the common rules; their tab lists all they open, and you enter their rules there. A card's own tab shows only what differs on it: rules for that card alone, and common rules closed on it. In the Common tab the card buttons close or open a rule on one card. Turn a rule off to try something without deleting it; it comes back as it was when you turn it on. With a source, only that address or network may use the port. Before a change that can cut off your connection, calls or phones, the page tells you what it will do.