Here's what I want to do: Prevent users on a small business network from bypassing my router's DNS via static IP settings. How? By capturing Port 53 requests to external IP's and forwarding them to my router. Example: User makes request to 188.8.131.52 port 53 Capture and forward request to 192.168.0.1 port 53 I can already forward by IP - I don't want to have long lists of IP forwards - I want to capture the port, not the IP. Any ideas on making this work?