Draytek 2750 manual Basics for Firewall, Denial of Service DoS Defense

4.5 Firewall

Basics for Firewall

While the broadband users demand more bandwidth for multimedia, interactive applications, or distance learning, security has been always the most concerned. The firewall of the Vigor router helps to protect your local network against attack from unauthorized outsiders. It also restricts users in the local network from accessing the Internet. Furthermore, it can filter out specific packets that trigger the router to build an unwanted outgoing connection.

Denial of Service (DoS) Defense

The DoS Defense functionality helps you to detect and mitigate the DoS attack. The attacks are usually categorized into two types, the flooding-type attacks and the vulnerability attacks. The flooding-type attacks will attempt to exhaust all your system's resource while the vulnerability attacks will try to paralyze the system by offending the vulnerabilities of the protocol or operation system.

The DoS Defense function enables the Vigor router to inspect every incoming packet based on the attack signature database. Any malicious packet that might duplicate itself to paralyze the host in the secure LAN will be strictly blocked and a Syslog message will be sent as warning, if you set up Syslog server.

Also the Vigor router monitors the traffic. Any abnormal traffic flow violating the pre-defined parameter, such as the number of thresholds, is identified as an attack and the Vigor router will activate its defense mechanism to mitigate in a real-time manner.

Below shows the menu items for Firewall.

Note: The firewall rules configured in this section cannot be applied to the computers connecting to the router via wireless LAN.

4.5.1 DoS Defense

Click Firewall and click DoS Defense to open the setup page. Storm control for the switch is configured on this page.

Frame Type	Set the Unicast storm rate control, multicast storm rate control,
	and a broadcast storm rate control for your router.
Status	Check this box to enable storm control status for the frame type.
Vigor2750 Series User’s Guide	147