Справочник Пользователя для ZyXEL Communications Corporation NBG4104
NBG4104 User’s Guide
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Firewall
18.1 Overview
Use these screens to enable and configure the firewall that protects your NBG4104 and your LAN
from unwanted or malicious traffic.
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:
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.
• 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).
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 56
Default Firewall Action
18.2 What You Can Do
• Use the General screen to enable or disable the NBG4104’s firewall (
).
• Use the Access Control Rule screen to view the configured access control rules and edit or
remove a rule (
• Use the Services screen to configure the NBG4104’s ICMP settings (
).
WAN
LAN
3
4
4
1
2
2
A