ZyXEL Communications ZyWALL 10, Руководство пользователя

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ZyWALL 10 Internet Security Gateway
14-2 Introducing the ZyWALL Firewall
Figure 14-3 Menu 21.2 - Firewall Setup
Please note that you can only configure the firewall rules using the ZyWALL Web
Configurator or CLI commands.
14.1.1 View Firewall Log
Enter option 3 from menu 21 to view the firewall log. Firewall logs may also be viewed from the ZyWALL
Web Configurator or may be sent to a syslog server using SMT Menu 24.3.2 - System Maintenance -
UNIX Syslog and setting the Firewall log field to Yes . Attack types that may display in the “Reason”
column are briefly described next.
14.1.2 Attack Types
Land
In a LAND Attack, hackers flood SYN packets into the network with a spoofed source IP address of the
targeted system. This makes it appear as if the host computer sent the packets to itself, making the system
unavailable while the target system tries to respond to itself.
IP Spoofing
IP Spoofing may be used to break into systems, to hide the hacker's identity, or to magnify the effect of the
DoS attack. IP Spoofing is a technique used to gain unauthorized access to computers by tricking a router or
firewall into thinking that the communications are coming from within the trusted network. To engage in IP
spoofing, a hacker must modify the packet headers so that it appears that the packets originate from a trusted
host and should be allowed through the router or firewall. The ZyWALL blocks all IP Spoofing attempts.
Menu 21.2 - Firewall Setup
The firewall protects against Denial of Service (DOS) attacks when
it is active. The default Policy sets
1. allow all sessions originating from the LAN to the WAN and
2. deny all sessions originating from the WAN to the LAN
You may define additional Policy rules or modify existing ones but
please exercise extreme caution in doing so
Active: No
LAN-to-WAN Set Name: ACL Default Set
WAN-to-LAN Set Name: ACL Default Set
Please configure the Firewall function through ZyWALL Web
Configurator.
Press ENTER to Confirm or ESC to Cancel: