Hello, I have a Fedora Core 3 computer with Shorewall installed. I have also installed IPTraf on this computer so I can see what sort of traffic appears on my external interface. I am seeing plenty of TCP and UDP traffic. The TCP traffic looks good in that I see plenty of 'To' traffic but no corresponding 'From' traffic as would be expected. However, there are several UDP port numbers ( 514, 520, 513,
68, 67 and some NetBios ports too) that have plenty of 'From' traffic which must mean that my firewall is generating packets in response to UDP traffic being received on my external interface. Should this be happening? If I go to ShieldsUp only Port 113 shows with a status of closed (which I will fix later). Does this have something to do with UDP being a connectionless protocol? Thank you.