ZyXEL Communications ADSL 2+ Gateway P-660HW-T1 - Manual (Page 151)

P-660H/HW/W-T Series User’ Guide
151 Chapter 11 Firewall Configuration
Whenever the number of half-open sessions with the same destination host address rises above
a threshold (TCP Maximum Incomplete), the Prestige starts deleting half-open sessions
according to one of the following methods:
• If the Blocking Time timeout is 0 (the default), then the Prestige deletes the oldest
existing half-open session for the host for every new connection request to the host. This
ensures that the number of half-open sessions to a given host will never exceed the
threshold.
• If the Blocking Time timeout is greater than 0, then the Prestige blocks all new
connection requests to the host giving the server time to handle the present connections.
The Prestige continues to block all new connection requests until the Blocking Time
expires.
11.12.3 Configuring Firewall Thresholds
The Prestige 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 62 Firewall: Threshold
The following table describes the labels in this screen.