ZyXEL NBG-416N Guia Do Utilizador

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NBG-416N User’s Guide
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Firewall
12.1  Overview   
Use these screens to enable and configure the firewall that protects your NBG-
416N and your LAN from unwanted or malicious traffic.
Enable the firewall to protect your LAN computers from attacks by hackers on the 
Internet and control access between the LAN and WAN. By default the firewall:
• allows traffic that originates from your LAN computers to go to all of the 
networks. 
• blocks traffic that originates on the other networks from going to the LAN. 
The following figure illustrates the default firewall action. User A can initiate an IM 
(Instant Messaging) session from the LAN to the WAN (1). Return traffic for this 
session is also allowed (2). However other traffic initiated from the WAN is blocked 
(3 and 4).
Figure 64   Default Firewall Action
12.2  What You Can Do
• Use  the  General screen to enable or disable the NBG-416N’s firewall (