ZyXEL Communications 2602H Series Chapter, Chapter, Chapter, Chapter, Firewall Configuration

Prestige 2602H/HW Series User’s Guide

Chapter 11
Dynamic DNS Setup.............................................................................................		161
11.1 Dynamic DNS .................................................................................................		161
11.1.1 DYNDNS Wildcard ................................................................................		161
11.2 Configuring Dynamic DNS .............................................................................		161
Chapter 12
Time and Date.......................................................................................................		163
12.1	Pre-defined NTP Time Servers List ................................................................	163
12.2	Configuring Time and Date ............................................................................	163
Chapter 13
Firewalls................................................................................................................		167
13.1	Firewall Overview ...........................................................................................	167
13.2	Types of Firewalls ..........................................................................................	167
13.2.1 Packet Filtering Firewalls ......................................................................		167
13.2.2 Application-level Firewalls ....................................................................		167
13.2.3 Stateful Inspection Firewalls ................................................................		168
13.3	Introduction to ZyXEL’s Firewall .....................................................................	168
13.3.1 Denial of Service Attacks ......................................................................		169
13.4	Denial of Service ............................................................................................	169
13.4.1 Basics ...................................................................................................		169
13.4.2 Types of DoS Attacks ...........................................................................		170
	13.4.2.1 ICMP Vulnerability ......................................................................	172
	13.4.2.2 Illegal Commands (NetBIOS and SMTP) ....................................	172
	13.4.2.3 Traceroute ...................................................................................	173
13.5	Stateful Inspection ..........................................................................................	173
13.5.1 Stateful Inspection Process ..................................................................		174
13.5.2 Stateful Inspection and the Prestige .....................................................		175
13.5.3 TCP Security .........................................................................................		175
13.5.4 UDP/ICMP Security ..............................................................................		176
13.5.5 Upper Layer Protocols ..........................................................................		176
13.6	Guidelines for Enhancing Security with Your Firewall ....................................	176
13.6.1 Security In General ...............................................................................		177
13.7	Packet Filtering Vs Firewall ............................................................................	178
13.7.1 Packet Filtering: ....................................................................................		178
	13.7.1.1 When To Use Filtering .................................................................	178
13.7.2 Firewall .................................................................................................		178
	13.7.2.1 When To Use The Firewall ..........................................................	178
Chapter 14
Firewall Configuration .........................................................................................		181
14.1	Access Methods .............................................................................................	181

16 Table of Contents