User`s manual

Conﬁguring Firewall

RX3042H User's Manual

The RX3042H has an Attack Defense Engine that protects internal

networks from Denial of Service (DoS) attacks such as SYN

flooding, IP smurfing, LAND, Ping of Death and all re-assembly

attacks. It can drop ICMP redirects and IP loose/strict source

routing packets. For example, a security device with the RX3042H

Firewall provides protection from “WinNuke”, a widely used program

to remotely crash unprotected Windows systems in the Internet.

The RX3042H Firewall also provides protection from a variety

of common Internet attacks such as IP Spoofing, Ping of Death,

Land Attack, and Reassembly attacks. For a complete list of DoS

protection provided by the RX3042H, please see Table 2.1.

9.3.2.1 DoS Protection Conﬁguration Parameters

Table 9.2 provides explanation for each type of DoS attacks. You

may check or uncheck the check box to enable or disable the

protection for each type DoS attacks.

Table 9.2. DoS Attack Deﬁnition

Field Description

IP Source Route

Intruder uses “source routing” in order to break into the

target system.

IP Spooﬁng

Spoofing is the creation of TCP/IP packets using

somebody elseʼs IP address. IP spooﬁng is an integral

part of many network attacks that do not need to see

responses.

Land

Attacker sends out packets to the system with the

same source and destination IP address being that of

the target system and causes the target system trying

to resolve an inﬁnite series of connections to itself. This

can cause the target system to slow down drastically.

Ping of Death

An attacker sends out larger than 64KB packets to

cause certain operating system to crash.

Smurf

An attacker issues ICMP echo requests to some

broadcast addresses. Each datagram has a spoofed

IP source address to be that of a real target-host. Most

of the addressed hosts will respond with an ICMP

echo reply, but not to the real initiating host, instead all

replies carry the IP address of the previously spoofed

host as their current destination and cause the victim

host or network to slow down drastically.