User's Manual

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Firewall
Firewall and Access Control
Your router includes a full SPI (Stateful Packet Inspection) rewall for controlling Internet access
from your LAN, as well as helping to prevent attacks from hackers. In addition to this, when using
NAT (Network Address Translation) the router acts as a “natural” Internet rewall, since all PCs
on your LAN use private IP addresses that cannot be directly accessed from the Internet. See the
WAN conguration section for more details on NAT.
Firewall: Prevents access from outside your network.
NAT natural rewall: This masks LAN users’ IP addresses, which are invisible to outside users on
the Internet, making it much more difcult for a hacker to target a machine on your network. This
natural rewall is on when the NAT function is enabled.
Firewall Security and Policy (General Settings): Inbound direction of Packet Filter rules prevent
unauthorized computers or applications accessing your local network from the Internet.
Intrusion Detection: Enable Intrusion Detection to detect, prevent, and log malicious attacks.
MAC Filter rules: Prevents unauthorized computers accessing the Internet.
URL Filter: Blocks PCs on your local network from unwanted websites.
A detailed explanation of each of the following items appears in the Firewall section below: Packet
Filter, MAC Filter, Intrusion Detection, Block WAN PING and URL Filter.