The anti-spam system based on feedback allows control of spam by the entire community of users FNS.
Each FNS user has the possibility & agrave; leave positive or negative feedback for each day that the sender has sent an e-mail; in this way the examination of an e-mail content is not & egrave; pi & ugrave; done by heuristic programs, probabilistici or deterministici, bens & igrave; the man who knows how to recognize with much more & ugrave; Precision an email containing spam.
The feedback are added arithmetically and are collected for each e-mail address to which a FNS user has decided to leave one. If an e-mail address has reached a total of 3 negative feedback, the sender will be & agrave; refused delivery at all mailboxes FNS no possibility & agrave; rehabilitation. This strict policy combined with anti-spam control and man-made, anyway, with general anti-spam programs installed in the mail server FNS it allows a mailbox free from spam more likely & agrave;.
The possible abuse of negative feedback & egrave; limited thanks to the fact that a user can set only one FNS feedback (negative or positive) per day for each e-mail address of a sender, and the fact that not c '& egrave; instead limit for the sum of the positive feedback received from the same sender. Thereby, while wanting to purposely set up to 3 negative feedback at a sender who did not send spam, It could not aim because the majority of users FNS has left the supposedly many more & ugrave; positive feedback over 24 ore.