D-Link 800 - DFL 800 - Security Appliance, User Manual, Page: 424 / 469

and put it into the Selected list.
3. Click OK
Configure an HTTP threshold of 10 connections/second:
1. Go to Traffic Management > Threshold Rules > Add > Threshold Rule
2. For the Threshold Rule enter:
• Name: HTTP-Threshold
• Service: http
3. For Address Filter enter:
• Source Interface: The firewall's management interface
• Destination Interface: any
• Source Network: 192.168.2.0/24 (or the object name)
• Destination Network: all-nets
4. Click OK
Specify the threshold, the threshold type and the action to take if exceeded:
1. Go to Add > Threshold Action
2. Configure the Theshold Action as follows:
• Action: Protect
• Group By: Host-based
• Threshold: 10
• Set the units for the threshold value to be Connections/Second
• Tick the Use ZoneDefense checkbox
• Click OK
12.3.4. ZoneDefense with Anti-Virus Scanning
ZoneDefense can be used in conjuction with the NetDefendOS Anti-Virus scanning feature.
NetDefendOS can first identify a virus source through antivirus scanning and then block the source
by communicating with switches configured to work with ZoneDefense. This feature is activated
through the following ALGs:
• HTTP - ZoneDefense can block an HTTP server that is a virus source.
• FTP - ZoneDefense can block a local FTP client that is uploading viruses.
• SMTP - ZoneDefense can block a local SMTP client that is sending viruses with emails.
This feature is described further in Section 6.4, “Anti-Virus Scanning” and in the sections covering
the individual ALGs.
12.3.5. Limitations
There are some differences in ZoneDefense operation depending on switch model. The first
difference is the latency between the triggering of a blocking rule to the moment when switch(es)
actually starts blocking out the traffic matched by the rule. All switch models require a short period
of latency time to implement blocking once the rule is triggered. Some models can activate blocking
12.3.4. ZoneDefense with Anti-Virus
Scanning Chapter 12. ZoneDefense
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