Configure settings for FTP Pasv Mode.
Use your local IP.
If you are assigned a fixed IP by your ISP, enter it in the box.
Get IP from a web file
Get your internet IP from a web file, like: http://ip.wftpserver.com/w/getIP.php
If you are assigned a dynamic IP and are using a service like dyndns.org (or other) to keep your domain name pointing to your IP, enter the host name in the edit box.
Update IP address interval
If you get your IP from web file or DNS, the server will update it at intervals.
Passive port range
This is the range of ports that the server will use with passive mode(it is to simplify use of forwarding rule in router for example).