ZyXEL Communications ZYWALL10 - Manual (Page 184)

ZyWALL 10 Internet Security Gateway
Introducing the ZyWALL Web Configurator 15-7
Figure 15-5 E-mail Log
15.4 Attack Alert
The first defense against DOS attacks. In this screen you may choose to generate an alert whenever an attack
is detected. For DoS attacks, the ZyWALL uses thresholds to determine when to drop sessions that do not
become fully established. These thresholds apply globally to all sessions.
You can use the default threshold values, or you can change them to values more suitable to your security
requirements.
15.4.1 Threshold Values:
Tune these parameters when something is not working and after you have checked the firewall counters.
These default values should work fine for normal small offices with ADSL bandwidth. Factors influencing
choices for threshold values are:
1. The maximum number of opened sessions.
2. The minimum capacity of server backlog in your LAN network.
3. The CPU power of servers in your LAN network.
4. Network bandwidth.
Subject:
Firewall Alert From ZyWALL
Date:
Fri, 07 Apr 2000 10:05:42
From:
[email protected]
To:
[email protected]
1|Apr 7 00 |From:192.168.1.1 To:192.168.1.255 |default permit
|forward
| 09:54:03 |UDP src port:00520 dest port:00520 |<1,00> |
2|Apr 7 00 |From:192.168.1.131 To:192.168.1.255 |default permit
|forward
| 09:54:17 |UDP src port:00520 dest port:00520 |<1,00> |
3|Apr 7 00 |From:192.168.1.6 To:10.10.10.10 |match |forward
| 09:54:19 |UDP src port:03516 dest port:00053 |<1,01> |
……………………………..{snip}…………………………………..
……………………………..{snip}…………………………………..
126|Apr 7 00 |From:192.168.1.1 To:192.168.1.255 |match
|forward
| 10:05:00 |UDP src port:00520 dest port:00520 |<1,02> |
127|Apr 7 00 |From:192.168.1.131 To:192.168.1.255 |match
|forward
| 10:05:17 |UDP src port:00520 dest port:00520 |<1,02> |
128|Apr 7 00 |From:192.168.1.1 To:192.168.1.255 |match
|forward
| 10:05:30 |UDP src port:00520 dest port:00520 |<1,02> |
End of Firewall Log
The date format
here is
Day-Month-Year.
The date format
here is Month-Day-
Year. The time
format is Hour-
Minute-Second.
"End of Log"
message shows that
a complete log has
been sent.
You may edit the
subject title