Symantec 11105111 - SYM MAIL SEC SMTP 5.0 SMS PORT MEDIA CD EN, User Manual

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99 Setting your antispam policy
Identifying spam using Symantec Premium AntiSpam
Identifying spam using Symantec Premium
AntiSpam
In addition to providing real-time blacklisting and sender and recipient
whitelisting, Symantec Premium AntiSpam uses the following to identify and
handle spam:
Reputation service Symantec monitors email sources to determine how much of the
mail that is sent from those sources is legitimate. Email from those
sources can then be blocked or allowed based on the reputation
value of the source as determined by Symantec.
Symantec uses the following lists to filter your messages:
■
Open proxy list: A dynamic database that contains the IP
addresses of identity-making relays, including proxy servers
with open or insecure ports.
■
Safe list: A list of IP addresses from which virtually no outgoing
email is spam.
■
Suspect list: A list of IP addresses from which virtually all of
the outgoing email is spam.
Suspected spam
threshold The premium antispam service calculates a spam score from 1 to
100 for each message. If a message scores from 90 to 100, it is
defined as spam. This range is not configurable. For more aggressive
filtering, you can define a spam threshold below 90 and above 24 to
identify suspected spam. You specify actions for handling spam and
suspected spam separately.
Language
identification The premium antispam service can determine the language in which
a filtered message is written. You can configure the premium
antispam service to automatically route messages that are written in
certain languages to a spam folder in the recipient’s mailbox.
To use this feature, you must deploy the optional plug-in for
Microsoft Outlook to the desktop computers on your network. The
plug-in is available on the Symantec Mail Security for SMTP
installation CD.