ZyXEL Communications p-2612HNU-FX Manuel D’Utilisation

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P-2612HNU-Fx User’s Guide
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Firewall
14.1  Overview
Use the ZyXEL Device firewall screens to enable and configure the firewall that 
protects your ZyXEL Device and network from attacks by hackers on the Internet 
and control access to it. By default the firewall:
• allows traffic that originates from your LAN computers to go to all other 
networks. 
• blocks traffic that originates on 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 69   Default Firewall Action
14.1.1  What You Can Do in the Firewall Screens
Use the Firewall screen (
) to enable LAN-to-WAN 
services blocking on the ZyXEL Device.
14.1.2  What You Need to Know About Firewall
The following terms and concepts may help as you read this chapter.
WAN
LAN
3
4
1
2
A