Black List Hosts - ZyXEL Communications Prestige 623 series User Manual

FIELD
Blacklist Period (min)
Attack Protection
Dos Protection
Max Half open TCP
conn.
Max ICMP conn.
Max Single Host conn.
Log Destination
E-Mail ID of Admin 1 - 3
Click Submit to confirm your changes. Refer to the section on Committing Your Changes and Rebooting
the Prestige to save your changes to permanent memory and make your changes take effect.

14.2.1 Black List Hosts

In the Firewall Configuration screen, click Black List to view the list of malicious hosts.
Firewall
Table 14-1 Firewall Configuration
Enter the time duration (in minutes) after which the external host IP address
will be removed from the blacklist.
Select Enable to protect against the use of malicious IP address hijacked by
hackers, network packet flooding or OS vulnerabilities.
Otherwise select Disable.
Select Enable to protect against Denial of Service (DoS) attacks. Otherwise
select Disable.
Sets the percentage of concurrent IP sessions that can be in the half-open
state.
In ordinary TCP communication, packets are in the half-open state only briefly
as a connection is being initiated; the state changes to active when packets
are being exchanged, or closed when the exchange is complete.
TCP connections in the half-open state can use up the available IP sessions. If
the percentage is exceeded, then the half-open sessions will be closed and
replaced with new sessions as they are initiated.
Specifies a maximum number of ICMP connections allowed. Newer ICMP
packets are allowed by removing older ICMP sessions.
Specifies a maximum number of connection sessions allowed. All further
connection requests are dropped until the older sessions time-out.
Specifies how attempted violations of the firewall settings will be tracked.
Select Trace to send records of such events via Ethernet to a system utility.
Select Email to e-mail the logs to the administrators) specified below.
If you select Email in the Log Destination field, enter the e-mail address(es)
to which the logs are sent.
Prestige 623 Series Dual-link ADSL Router
DESCRIPTION
14-3