ZyXEL Communications G.SHDSL.bis 4-port Security Gateway P-793H - Manual (Page 149)

P-793H User’s Guide
Chapter 9 Firewall Configuration 149
9.10.3 Configuring Firewall Thresholds
The ZyXEL Device also sends alerts whenever TCP Maximum Incomplete is exceeded. The
global values specified for the threshold and timeout apply to all TCP connections.
Click Firewall, and Threshold to bring up the next screen.
Figure 67 Firewall > Threshold
The following table describes the labels in this screen.
Table 44 Firewall > Threshold
LABEL DESCRIPTION
Denial of Service
Thresholds
One Minute Low Type the rate of new half-open sessions that causes the firewall to stop deleting
half-open sessions. The ZyXEL Device continues to delete half-open sessions
as necessary, until the rate of new connection attempts drops below this
number. See One Minute High for an example.
One Minute High Type 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 ZyXEL Device deletes half-open sessions as required to
accommodate new connection attempts.
For example, if One Minute Low is 80 and One Minute High is 100, the ZyXEL
Device starts deleting half-open sessions when more than 100 session
establishment attempts have been detected in the last minute and stops deleting
half-open sessions when fewer than 80 session establishment attempts have
been detected in the last minute.
Maximum
Incomplete Low
Type the number of existing half-open sessions that causes the firewall to stop
deleting half-open sessions. The ZyXEL Device continues to delete half-open
requests as necessary, until the number of existing half-open sessions drops
below this number. See Maximum Incomplete High for an example.