802.11g Wireless 4-port Router User's Guide
Table Of Contents
- User’s Guide
- Copyright
- Federal Communications Commission (FCC) Interference Statement
- ZyXEL Limited Warranty
- Customer Support
- Table of Contents
- List of Figures
- List of Tables
- Preface
- Getting to Know Your ZyAIR
- 1.1 Introducing the ZyAIR
- 1.2 ZyAIR Features
- 1.2.1 Physical Features
- 1.2.2 Firmware Features
- 1.2.2.1 Internal RADIUS Server
- 1.2.2.2 Wi-Fi Protected Access
- 1.2.2.3 802.11b Wireless LAN Standard
- 1.2.2.4 802.11g Wireless LAN Standard
- 1.2.2.5 STP (Spanning Tree Protocol) / RSTP (Rapid STP)
- 1.2.2.6 Certificates
- 1.2.2.7 Limit the number of Client Connections
- 1.2.2.8 SSL Passthrough
- 1.2.2.9 Firewall
- 1.2.2.10 Brute-Force Password Guessing Protection
- 1.2.2.11 Wireless LAN MAC Address Filtering
- 1.2.2.12 WEP Encryption
- 1.2.2.13 IEEE 802.1X Network Security
- 1.2.2.14 Universal Plug and Play (UPnP)
- 1.2.2.15 Dynamic DNS Support
- 1.2.2.16 PPPoE Support (RFC2516)
- 1.2.2.17 PPTP Encapsulation
- 1.2.2.18 Network Address Translation (NAT)
- 1.2.2.19 Traffic Redirect
- 1.2.2.20 NAT for Single-IP-address Internet Access
- 1.2.2.21 DHCP (Dynamic Host Configuration Protocol)
- 1.2.2.22 Multicast
- 1.2.2.23 IP Alias
- 1.2.2.24 IP Policy Routing
- 1.2.2.25 SNMP
- 1.2.2.26 Full Network Management
- 1.2.2.27 Logging and Tracing
- 1.2.2.28 Diagnostics Capabilities
- 1.2.2.29 Embedded FTP and TFTP Servers
- 1.2.2.30 Wireless Association List
- 1.2.2.31 Wireless LAN Channel Usage
- 1.3 Applications for the ZyAIR
- Introducing the Web Configurator
- Wizard Setup
- System Screens
- LAN Screens
- Wireless Configuration and Roaming
- Wireless Security
- 7.1 Wireless Security Overview
- 7.2 Security Parameters Summary
- 7.3 WEP Overview
- 7.4 Configuring WEP Encryption
- 7.5 Introduction to WPA
- 7.6 Configuring WPA-PSK Authentication
- 7.7 Wireless Client WPA Supplicants
- 7.8 Configuring WPA Authentication
- 7.9 Introduction to RADIUS
- 7.10 Configuring RADIUS
- 7.11 802.1x Overview
- 7.12 Dynamic WEP Key Exchange
- 7.13 Configuring 802.1x and Dynamic WEP Key Exchange
- 7.14 Configuring 802.1x and Static WEP Key Exchange
- 7.15 Configuring 802.1x
- 7.16 MAC Filter
- Internal RADIUS Server
- WAN
- Single User Account (SUA) / Network Address Translation (NAT)
- Static Route Screens
- Remote Management Screens
- UPnP
- Firewalls
- Firewall Screens
- Content Filtering
- Certificates
- 17.1 Certificates Overview
- 17.2 Self-signed Certificates
- 17.3 Configuration Summary
- 17.4 My Certificates
- 17.5 Certificate File Formats
- 17.6 Importing a Certificate
- 17.7 Creating a Certificate
- 17.8 My Certificate Details
- 17.9 Trusted CAs
- 17.10 Importing a Trusted CA’s Certificate
- 17.11 Trusted CA Certificate Details
- Log Screens
- Maintenance
- Introducing the SMT
- General Setup
- Menu 2 WAN Setup
- LAN Setup
- Internet Access
- Remote Node Configuration
- Static Route Setup
- Dial-in User Setup
- Network Address Translation (NAT)
- Filter Configuration
- Enabling the Firewall
- SNMP Configuration
- System Security
- System Information and Diagnosis
- Firmware and Configuration File Maintenance
- System Maintenance and Information
- Remote Management
- Call Scheduling
- Appendix A
- Appendix B
- Appendix C
- Appendix D
- Appendix E
- Appendix F
- Appendix G
- Appendix H
- Appendix I
- Appendix J
- Appendix K
- Appendix L
- Index

ZyAIR G-2000 Plus User’s Guide
193 Chapter 15 Firewall Screens
You may define additional rules and sets or modify existing ones but please exercise extreme
caution in doing so.
Note: If you configure firewall rules without a good
understanding of how they work, you might inadvertently
introduce security risks to the firewall and to the protected
network. Make sure you test your rules after you configure
them.
For example, you may create rules to:
• Block certain types of traffic, such as IRC (Internet Relay Chat), from the LAN to the
Internet.
• Allow certain types of traffic, such as Lotus Notes database synchronization, from
specific hosts on the Internet to specific hosts on the LAN.
• Allow everyone except your competitors to access a Web server.
• Restrict use of certain protocols, such as Telnet, to authorized users on the LAN.
These custom rules work by comparing the Source IP address, Destination IP address and IP
protocol type of network traffic to rules set by the administrator. Your customized rules take
precedence and override the ZyAIR’s default rules.
15.3 Rule Logic Overview
Note: Study these points carefully before configuring rules.
15.3.1 Rule Checklist
1 State the intent of the rule. For example, This restricts all IRC access from the LAN to the
Internet. Or, This allows a remote Lotus Notes server to synchronize over the Internet to
an inside Notes server.
2 Is the intent of the rule to forward or block traffic?
3 What direction of traffic does the rule apply to (See “Types of Firewalls” on page 178)?
4 What IP services will be affected?
5 What computers on the LAN are to be affected (if any)?
6 What computers on the Internet will be affected? The more specific, the better. For
example, if traffic is being allowed from the Internet to the LAN, it is better to allow only
certain machines on the Internet to access the LAN.