ZyXEL Communications 792H - Manual (Page 15)

Prestige 792H G.SHDSL Router
Table of Contents ix
5.12 Response Strings ......................................................................................................................5-18
5.13 Configuring Advanced Modem Setup......................................................................................5-18
Chapter 6 Network Address Translation (NAT)........................................................................................6-1
6.1 NAT Overview...........................................................................................................................6-1
6.1.1 NAT Definitions.........................................................................................................................6-1
6.1.2 What NAT Does.........................................................................................................................6-1
6.1.3 How NAT Works .......................................................................................................................6-2
6.1.4 NAT Application........................................................................................................................6-2
6.1.5 NAT Mapping Types .................................................................................................................6-3
6.2 SUA (Single User Account) Versus NAT..................................................................................6-4
6.3 SUA Server ................................................................................................................................6-5
6.3.1 Port Forwarding: Services and Port Numbers ............................................................................6-5
6.3.2 Configuring Servers Behind SUA (Example) ............................................................................6-6
6.4 Selecting the NAT Mode............................................................................................................6-7
6.5 Configuring SUA Server............................................................................................................6-8
6.6 Configuring Address Mapping.................................................................................................6-10
6.7 Editing an Address Mapping Rule ...........................................................................................6-12
Chapter 7 Dynamic DNS Setup...................................................................................................................7-1
7.1 Dynamic DNS ............................................................................................................................7-1
7.1.1 DYNDNS Wildcard ...................................................................................................................7-1
7.2 Configuring Dynamic DNS........................................................................................................7-1
Chapter 8 Firewalls......................................................................................................................................8-1
8.1 Firewall Overview......................................................................................................................8-1
8.2 Types of Firewalls......................................................................................................................8-1
8.2.1 Packet Filtering Firewalls...........................................................................................................8-1
8.2.2 Application-level Firewalls ........................................................................................................8-1
8.2.3 Stateful Inspection Firewalls......................................................................................................8-2
8.3 Introduction to ZyXEL’s Firewall..............................................................................................8-2
8.4 Denial of Service........................................................................................................................8-3
8.4.1 Basics .........................................................................................................................................8-3
8.4.2 Types of DoS Attacks ................................................................................................................8-4
8.5 Stateful Inspection......................................................................................................................8-7
8.5.1 Stateful Inspection Process.........................................................................................................8-8
8.5.2 Stateful Inspection and the Prestige ...........................................................................................8-9
8.5.3 TCP Security ............................................................................................................................8-10
8.5.4 UDP/ICMP Security.................................................................................................................8-10
8.5.5 Upper Layer Protocols .............................................................................................................8-11
8.6 Guidelines for Enhancing Security with Your Firewall ...........................................................8-11
8.6.1 Security In General ..................................................................................................................8-11
8.7 Packet Filtering Vs Firewall.....................................................................................................8-12
8.7.1 Packet Filtering: .......................................................................................................................8-12