What does the PORT IP Mode = Auto mean?

Hello all

my question is written in the title ;-)
What is the effect, if I set this option(Tools-Settings-Connection) to auto?

Greets
Azrael

Auto gets your ip from internet conecting to smartftp server to check your real ip and no the ip of your network adapter. For example:

[14:42:32] Connecting IP Repeater "repeater.smartftp.com" ...
[14:42:32] IP Repeater returned: "217.127.xxx.xxx"
[14:42:32] PORT 217,127,xxx,xxx,14,131