InterScanTM Messaging Security Virtual Appliance - Online Help ...

Configuring IP Filtering Settings
• Threshold: The maximum percentage of spam email messages that IMSVA
will allow during the value you set for Duration to monitor above. The
threshold is a fraction with a numerator and denominator:
• Rate (%): Type the maximum number of allowable email messages with
spam threats (the numerator).
• Total mails: Type the total number of spam email messages out of which
the threshold percentage is calculated (the denominator).
Consider the following example.
Duration to monitor: 1 hour at a rate of 20 out of 100
During each one-hour period that spam blocking is active, IMSVA starts
blocking IP addresses when more than 20% of the messages it receives contain
spam and the total number of messages exceeds 100.
5. Next to Triggering action, select one of the following:
• Block temporarily: Block email messages from the IP address and allow the
upstream MTA to try again.
• Block permanently: Never allow another email message from the IP address
and do not allow the upstream MTA to try again.
6. Click Save.
To specify IP Filtering virus settings:
1. Choose IP Filtering > Rules from the menu. The Rules screen appears with 4
tabs, one for each type of threat.
2. Click the Virus tab. The Virus screen appears.
3. Select the Enable check box to enable blocking of viruses.
4. Configure the following:
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