Belkin F5D5730au Defaults, Manually Configuring your Modem, section, Parameter, Description

Manually Configuring your Modem

Network attacks that deny access to a network device are called DoS attacks.

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 Modem protects against DoS attacks including: 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.

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	Yes	The Intrusion Detection feature of
and Anti-		the VoIP Modem limits the access
DoS firewall		of incoming traffic at the WAN port.
protection		When the Stateful Packet Inspection
		(SPI) 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.

Manually Configuring your Modem

Stateful Packet	This option allows you to select
Inspection	different application types that are
	using dynamic port numbers. If you
	wish to use Stateful Packet Inspection
	(SPI) for blocking packets, click on the
	Yes radio button in the “Enable SPI and
	Anti-DoS firewall protection” field and
	then check the inspection type that you
	need, such as Packet Fragmentation,
	TCP Connection, UDP Session, FTP
	Service, H.323 Service, and TFTP
	Service. It is called a “Stateful” packet
	inspection because it examines the
	contents of the packet to determine
	the state of the communication; i.e.,
	it ensures that the stated destination
	computer has previously requested the
	current communication. This is a way
	of ensuring that all communications are
	initiated by the recipient computer and
	are taking place only with sources that
	are known and trusted from previous
	interactions. In addition to being more
	rigorous in their inspection of packets,
	stateful inspection firewalls also
	close off ports until a connection to
	the specific port is requested. When
	particular types of traffic are checked,
	only the particular type of traffic
	initiated from the internal LAN will be
	allowed. For example, if the user only
	checks FTP Service in the Stateful
	Packet Inspection section, all incoming
	traffic will be blocked except for FTP
	connections initiated from the local
	LAN.
Discard Ping	Prevents a ping on the Modem’s WAN
from WAN	port from being routed to the network.
Discard

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