I have a 1721 router at home as my gateway to the internet and firewall, running fw ios 12.3.22. i have 5 static ips and currently using 2 internal networks each one on a different public ip. i have overloaded nat set up and the actual ip on the internet facing interface is in the middle of my range and at the moment not in use. the problem im having is return udp traffic. I do not want to permit everything inbound on the wan side so i set up an access list to allow the inbound traffic i needed and return udp traffic. The problem so far has been DNS. When i looked at the logged blocks it looks like the return dns traffic is going to a different port then 53. I am guessing this is due to the natting but i do not know what the best way to get around this is. i have the permit any any eq 53 but because the retrun traffic seems to be coming in on a different port.