In addition to the anti-spam analysis, you can complete the system in order to set up a doubt removal according to certain criteria: this is the HUMail technology (technology owned by the SECUSERVE Laboratory since 2019).
Principle Consists in checking that the sender of a suspicious message (according to his score) or which could represent a threat (Attachment or link to a website), is a real user (TURING TEST, control of humanity by sending a test: click on your logo in a web page, enter an alphanumeric captcha or perform a ReCAPTCHA test). If the sender is not a natural person but a "nice robot", you can of course release the message via an Interactive HUMail Report or the Individual Messaging Console.
Full documentation :
https://www.security-mail.net/documentation.php?action=download&id=141&lang=fr
HUMail technology has the ability to
distinguish between man and machine