If TCP is selected as the protocol when specifying a rule in the “Add Rule” and “Edit Rule” dialog boxes under Configuration>Network>Firewall Configuration in Expert mode, the additional fields shown in the following figure appear at the bottom of the screen.Firewall Configuration “Add Rule” and “Edit Rule” TCP Protocol Fields and Menu Options
A source or destination port number for filtering in the “Source Port” or “Destination Port” field. If a second number is entered in the “to” field, TCP packets are filtered for any port number within the range that starts with the first port number and that ends with the second. The TCP flags “SYN” (synchronize), “ACK” (acknowledge), “FIN” (finish), “RST” (reset), “URG ” (urgent) or “PSH” (push) cause TCP packets to be filtered for the specified flag and the selected condition, either “Any,” “Set,” or “Unset.”