On various dialogs and security features throughout MDaemon you will see options that allow you to choose whether or not "Trusted IPs" will be exceptions to or exempt from those options. The IP addresses you list on this screen are the ones to which those options refer.
Trusted IP addresses
This is the list of IP addresses that will be exempt from certain designated security options.
New trusted IP address
Enter a new IP address to be added to the Trusted IP Addresses list.
Comment
Use this for any comment text about an entry.
Add
Click this button to add the new IP address to the Trusted IP Addresses list.
Remove
Click this button to remove the selected entries from the Trusted IP Addresses list.