ZyXEL Communications 70 Series - Manual (Page 229)

ZyWALL 5/35/70 Series User’s Guide
229 Chapter 11 Firewall Screens
Figure 101 Firewall Threshold
The following table describes the labels in this screen.
Table 72 Firewall Threshold
LABEL DESCRIPTION
Disable DoS Attack
Protection on
Select the check box of an interface to which the ZyWALL does not apply the
thresholds. This disables DoS protection on the selected interface.
Denial of Service
Thresholds
One Minute Low This is the rate of new half-open sessions that causes the firewall to stop deleting
half-open sessions. The ZyWALL continues to delete half-open sessions as
necessary, until the rate of new connection attempts drops below this number.
One Minute High This is the rate of new half-open sessions that causes the firewall to start deleting
half-open sessions. When the rate of new connection attempts rises above this
number, the ZyWALL deletes half-open sessions as required to accommodate
new connection attempts.
The numbers, say 80 in the One Minute Low field and 100 in this field, cause the
ZyWALL to start deleting half-open sessions when more than 100 session
establishment attempts have been detected in the last minute, and to stop
deleting half-open sessions when fewer than 80 session establishment attempts
have been detected in the last minute.
Maximum
Incomplete Low
This is the number of existing half-open sessions that causes the firewall to stop
deleting half-open sessions. The ZyWALL continues to delete half-open requests
as necessary, until the number of existing half-open sessions drops below this
number.