ZyWALL 5/35/70 Series User’s Guide

Figure 101 Firewall Threshold

The following table describes the labels in this screen.

Table 72 Firewall Threshold

LABEL

DESCRIPTION

 

 

Disable DoS Attack

Select the check box of an interface to which the ZyWALL does not apply the

Protection on

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

This is the number of existing half-open sessions that causes the firewall to stop

Incomplete Low

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.

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Chapter 11 Firewall Screens