Only permissions to Anonymous in the Default receive connector

Hello,

I was wondering if I can set up the default receive connector to receive only from Anonymous, unticking the other permissions in the tab "Permissions". 

Also, if this connector is only used to receive emails from the internet, could I untick all the options in the "Authentication" tab of this default receive connector?.

Thanks in advance.

Luis Olías Técnico/Admon Sistemas . Sevilla (España - Spain)