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
81 Chapter 6 Wireless Configuration and Roaming
Figure 24 RTS/CTS
When station A sends data to the ZyAIR, it might not know that station B is already using the
channel. If these two stations send data at the same time, collisions may occur when both sets
of data arrive at the AP at the same time, resulting in a loss of messages for both stations.
RTS/CTS is designed to prevent collisions due to hidden nodes. An RTS/CTS defines the
biggest size data frame you can send before an RTS (Request To Send)/CTS (Clear to Send)
handshake is invoked.
When a data frame exceeds the RTS/CTS value you set (between 0 to 2432 bytes), the station
that wants to transmit this frame must first send an RTS (Request To Send) message to the AP
for permission to send it. The AP then responds with a CTS (Clear to Send) message to all
other stations within its range to notify them to defer their transmission. It also reserves and
confirms with the requesting station the time frame for the requested transmission.
Stations can send frames smaller than the specified RTS/CTS directly to the AP without the
RTS (Request To Send)/CTS (Clear to Send) handshake.
You should only configure RTS/CTS if the possibility of hidden nodes exists on your network
and the “cost” of resending large frames is more than the extra network overhead involved in
the RTS (Request To Send)/CTS (Clear to Send) handshake.
If the RTS/CTS value is greater than the Fragmentation Threshold value (see next), then the
RTS (Request To Send)/CTS (Clear to Send) handshake will never occur as data frames will
be fragmented before they reach RTS/CTS size.
Note: Enabling the RTS Threshold causes redundant network
overhead that could negatively affect the throughput
performance instead of providing a remedy.
Note:
6.2.2 Fragmentation Threshold
A Fragmentation Threshold is the maximum data fragment size (between 256 and 2432
bytes) that can be sent in the wireless network before the ZyAIR will fragment the packet into
smaller data frames.