ZyXEL Communications P-660HNU-Fx User Manual
ADSL Series User’s Guide
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H A P T E R
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Firewall
13.1 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:
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 and WLAN computers to go to all other networks.
• blocks traffic that originates on other networks from going to the LAN and WLAN.
• blocks traffic that originates on other networks from going to the LAN and WLAN.
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).
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 91
Default Firewall Action
13.1.1 What You Can Do in this Chapter
• Use the General screen to enable or disable the ZyXEL Device’s firewall (
• Use the Services screen to view the configured firewall rules and add, edit or remove a firewall
rule (
13.1.2 What You Need to Know
Firewall
The ZyXEL Device’s firewall feature physically separates the LAN/WLAN and the WAN and acts as a
secure gateway for all data passing between the networks.
secure gateway for all data passing between the networks.
WAN
LAN
3
4
4
1
2
2
A