Prestige 661H/HW Series User’s Guide
11 Table of Contents
8.1.4 NAT Application ...................................................................................... 116
8.1.5 NAT Mapping Types ............................................................................... 117
8.2 SUA (Single User Account) Versus NAT ..........................................................118
8.3 SUA Server ...................................................................................................... 118
8.3.1 Default Server IP Address ......................................................................118
8.3.2 Port Forwarding: Services and Port Numbers ........................................118
8.3.3 Configuring Servers Behind SUA (Example) ..........................................119
8.4 Selecting the NAT Mode ..................................................................................119
8.5 Configuring SUA Server ...................................................................................120
8.6 Configuring Address Mapping ..........................................................................122
8.7 Editing an Address Mapping Rule ....................................................................123
Chapter 9
Dynamic DNS Setup............................................................................................. 126
9.1 Dynamic DNS ...................................................................................................126
9.1.1 DYNDNS Wildcard ..................................................................................126
9.2 Configuring Dynamic DNS ...............................................................................126
Chapter 10
Time and Date....................................................................................................... 128
10.1 Configuring Time and Date ............................................................................128
Chapter 11
Firewalls................................................................................................................ 130
11.1 Firewall Overview ...........................................................................................130
11.2 Types of Firewalls ...........................................................................................130
11.2.1 Packet Filtering Firewalls ......................................................................130
11.2.2 Application-level Firewalls .....................................................................130
11.2.3 Stateful Inspection Firewalls ................................................................131
11.3 Introduction to ZyXEL’s Firewall .....................................................................131
11.3.1 Denial of Service Attacks ......................................................................132
11.4 Denial of Service ............................................................................................132
11.4.1 Basics ...................................................................................................132
11.4.2 Types of DoS Attacks ............................................................................133
11.4.2.1 ICMP Vulnerability ......................................................................135
11.4.2.2 Illegal Commands (NetBIOS and SMTP) ....................................135
11.4.2.3 Traceroute ...................................................................................136
11.5 Stateful Inspection ..........................................................................................136
11.5.1 Stateful Inspection Process ...................................................................137
11.5.2 Stateful Inspection and the Prestige .....................................................138
11.5.3 TCP Security .........................................................................................138
11.5.4 UDP/ICMP Security ..............................................................................139
11.5.5 Upper Layer Protocols ..........................................................................139
