I have set up Fedora Core 4 as a server (httpd, mysql and ftp). This server is behind a router. I have set port redirection on this router for ports 80, 20 and 21 to the server's local IP Address (192.168.1.100). I have subscribed to dyndns.com to resolve my dynamic ip to a fix named url. That works just fine. I don't have problems accessing the web pages on the server locally and from the internet. My problem is on FTP. I can do ftp from another machine in my local network by typing $ftp 192.168.1.100. However, I cannot do the same thing from the internet by typing $ftp <dyndns fix named url>:21.