C
ONFIGURING
THE
B
ARRICADE
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The Barricade’s firewall inspects packets at the application layer, maintains
TCP and UDP session information including timeouts and number of
active sessions, and provides the ability to detect and prevent certain types
of network attacks such as DoS attacks.
Network attacks that deny access to a network device are called
Denial-of-Service (DoS) attacks. Denial of Service (DoS) attacks are aimed
at devices and networks with a connection to the Internet. Their goal is
not to steal information, but to disable a device or network so users no
longer have access to network resources.
The Barricade protects against the following DoS attacks: Ping of Death
(Ping flood) attack, SYN flood attack, IP fragment attack (Teardrop
Attack), Brute-force attack, Land Attack, IP Spoofing attack, IP with zero
length, TCP null scan (Port Scan Attack), UDP port loopback, Snork
Attack etc.
Note: The firewall does not significantly affect system performance, so
we advise enabling the prevention features to protect your
network.
Parameter Defaults Description
Enable SPI and
Anti-DoS firewall
protection
Yes The Intrusion Detection feature of the Barricade
limits the access of the incoming traffic at the
WAN port. When the Stateful Packet Inspection
feature is turned on, all incoming packets are
blocked except those types marked with a check
in the Stateful Packet Inspection section at the
top of the screen.