ZyAIR Wireless Gateway Series User’s Guide

Table 11-4 Legal SMTP Commands

AUTH

DATA

EHLO

ETRN

EXPN

HELO

HELP

MAIL

NOOP

 

 

 

 

 

 

 

 

 

QUIT

RCPT

RSET

SAML

SEND

SOML

TURN

VRFY

 

 

 

 

 

 

 

 

 

 

Traceroute

Traceroute is a utility used to determine the path a packet takes between two endpoints. Sometimes when a packet filter firewall is configured incorrectly an attacker can traceroute the firewall gaining knowledge of the network topology inside the firewall.

4.Often, many DoS attacks also employ a technique known as "IP Spoofing" as part of their attack. IP Spoofing may be used to break into systems, to hide the hacker's identity, or to magnify the effect of the DoS attack. IP Spoofing is a technique used to gain unauthorized access to computers by tricking a router or firewall into thinking that the communications are coming from within the trusted network. To engage in IP spoofing, a hacker must modify the packet headers so that it appears that the packets originate from a trusted host and should be allowed through the router or firewall. The ZyAIR blocks all IP Spoofing attempts.

11.5 Stateful Inspection

Stateful inspection means the ZyAIR records packet information, such as port number and source/destination addresses and then allows or denies the response depending on your firewall rules.

The default rules allow LAN-to-WAN traffic and deny traffic initiated from WAN-to-LAN.

Introduction to Firewalls

11-7