Draytek Vigor2850 Series, Руководство пользователя

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Vigor2850 Series User’s Guide
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3 3 . . 4 4 . . 4 4 D D o o S S D D e e f f e e n n s s e e
As a sub-functionality of IP Filter/Firewall, there are 15 types of detect/ defense function in
the
DoS Defense
setup. The DoS Defense functionality is disabled for default.
Click
Firewall
and click
DoS Defense
to open the setup page.
Available settings are explained as follows:
Item Description
Enable Dos Defense
Check the box to activate the DoS Defense Functionality.
Select All
Click this button to select all the items listed below.
Enable SYN flood defense
Check the box to activate the SYN flood defense function.
Once detecting the Threshold of the TCP SYN packets from
the Internet has exceeded the defined value, the Vigor
router will start to randomly discard the subsequent TCP
SYN packets for a period defined in Timeout. The goal for
this is prevent the TCP SYN packets’ attempt to exhaust the
limited-resource of Vigor router. By default, the threshold
and timeout values are set to 50 packets per second and 10
seconds, respectively.
Enable UDP flood defense
Check the box to activate the UDP flood defense function.
Once detecting the Threshold of the UDP packets from the
Internet has exceeded the defined value, the Vigor router
will start to randomly discard the subsequent UDP packets
for a period defined in Timeout. The default setting for
threshold and timeout are 150 packets per second and 10
seconds, respectively.