Planet Networking & Communication CS-2001 User Manual page 455

Terms in Settings
Anti-Spam Filter Settings

Incoming and outgoing emails can be inspected.

Emails exceeding the threshold score can have a warning message added and a
score tag appended to the subject, whereas others below the threshold score can
only have a score tag appended in the subject line.

The inspection methods utilized:
 Verify with spam fingerprint database: Generates an ID number by
analyzing the email with algorithms, and then makes a comparison with the
spam ID list on the server.
 Enable spam signature push update: Generates a value by analyzing the
email with algorithms, and then compares it to the spam signatures on the
database.
 Greylist Filtering: Rejects the session requests from new senders for the
first time.
 Verify sender's IP with Real-Time Block List: Compares the sender's IP
address to the blacklist on the server.
 Enable Bayesian filtering: Compares the email header to the Bayesian
database.
 Enable Sender Policy Framework(SPF): Checks whether the sender's IP
address is identical with the one specified in the DNS SPF record.
 Enable DomainKey: Verifies the domain of an email sender and the
message integrity.

Configuring the filtering priority of Personal rules and Global rules.
Note：
1. Once the Proxy Server is deployed, the proxy settings under System > Configuration >
Settings must be configured for the CS-2001 to access the Internet.
2. The CS-2001 will apply its default spam filtering settings if no method has been selected.
3. Bayesian filtering is not effective unless at least 200 messages have been classified for spam
and ham individually.
Figure 13-1 The Amount of Spam and Ham in the Database
（Figure 13-1）
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