ZyXEL Communications Prestige 661H Series User Manual page 12

11.6 Guidelines for Enhancing Security with Your Firewall ....................................139
11.7 Packet Filtering Vs Firewall ............................................................................141
Chapter 12
Firewall Configuration ......................................................................................... 144
12.1 Access Methods .............................................................................................144
12.2 Firewall Policies Overview .............................................................................144
12.3 Rule Logic Overview ......................................................................................145
12.4 Connection Direction ......................................................................................146
12.5 Configuring Basic Firewall Settings ................................................................147
12.6 Rule Summary ...............................................................................................148
12.7 Customized Services .....................................................................................153
12.8 Creating/Editing A Customized Service .........................................................153
12.9 Example Firewall Rule ...................................................................................154
12.10 Predefined Services .....................................................................................158
12.11 Anti-Probing ..................................................................................................160
12.12 DoS Thresholds ...........................................................................................161
Chapter 13
Content Filtering .................................................................................................. 166
13.1 Content Filtering Overview .............................................................................166
13.2 Configuring Keyword Blocking .......................................................................166
13.3 Configuring the Schedule ..............................................................................167
13.4 Configuring Trusted Computers .....................................................................168
Table of Contents
11.6.1 Security In General ...............................................................................140
11.7.1 Packet Filtering: ....................................................................................141
11.7.1.1 When To Use Filtering .................................................................141
11.7.2 Firewall ..................................................................................................141
11.7.2.1 When To Use The Firewall ..........................................................141
12.3.1 Rule Checklist .......................................................................................145
12.3.2 Security Ramifications ..........................................................................145
12.3.3 Key Fields For Configuring Rules .........................................................146
12.3.3.1 Action ..........................................................................................146
12.3.3.2 Service ........................................................................................146
12.3.3.3 Source Address ...........................................................................146
12.3.3.4 Destination Address ....................................................................146
12.4.1 LAN to WAN Rules ...............................................................................146
12.4.2 Alerts .....................................................................................................147
12.6.1 Configuring Firewall Rules ....................................................................150
12.12.1 Threshold Values ................................................................................162
12.12.2 Half-Open Sessions ............................................................................162
12.12.2.1 TCP Maximum Incomplete and Blocking Time .........................162
Prestige 661H/HW Series User's Guide
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