F-SECURE INTERNET GATEKEEPER WINDOWS 2000-2003 SERVER 6.61 Administrator's Manual page 243

CHAPTER 8 243
Administering F-Secure Spam Control
When the heuristic spam analysis is
enabled, all messages that the threat
detection engine does not classify as spam
are further analyzed for spam.
When the heuristic spam analysis is
disabled, only the threat detection engine
scans inbound mails for spam.
Heuristic spam analysis slows down the
performance but improves the spam
detection rate.
Spam filtering level Specify the spam filtering level. Decreasing
the level allows less spam to pass, but more
regular mails may be falsely identified as
spam. Increasing the level allows more
spam to pass, but a smaller number of
regular e-mail messages will be falsely
identified as spam.
For example, if the spam filtering level is set
to 3, more spam is filtered, but also more
regular e-mails may be falsely identified as
spam. If the spam filtering level is set to 7,
more spam will pass undetected, but a
smaller number of regular mails will be
falsely identified as spam.
The allowed values are from 1 to 9.
The spam levels are determined by
calculating points for each e-mail. The spam
scanning involves a large number of different
rules, which give each e-mail different points
depending on the mail content and header
information. These points are then
calculated to a number between 1 and 9,
which defines the likelihood of the message
being spam.