User`s guide
Table Of Contents
- About This User's Guide
- Document Conventions
- Safety Warnings
- Table of Contents
- Part I: Introduction
- 1. Getting to Know Your MWR222
- 2.
- 2. Introducing the Web Configurator
- 3. Monitor
- 4.
- 4.
- 4. MWR222 Modes
- 5. Router Mode
- 6. Access Point Mode
- 5.
- 5.
- 7. WISP Mode
- 7
- 7
- 8 Tutorials
- 8.3 Connecting to Internet from an Access Point
- 8.4 Configuring Wireless Security Using WPS
- 9 Wireless LAN
- 9.1 Overview
- 9.2 What You Can Do
- Use the General screen to enable the Wireless LAN, enter the SSID and select the wireless security mode.
- 9.3 What You Should Know
- 9.4 General Wireless LAN Screen
- 9.5 Security
- 9.6 MAC Filter
- 9.7 Wireless LAN Advanced Screen
- 9.8 Quality of Service (QoS) Screen
- 9.9 WPS Screen
- 9.10 WPS Station Screen
- 9.11 Scheduling Screen
- 9.12 WDS Screen
- 10.1 Overview
- 10.2 What You Can Do
- 10.3 What You Need To Know
- 10.2
- 10.3
- 10.4 Internet Connection
- 10.5 Mobile WAN
- 10.7 IGMP Snooping Screen
- 11 LAN
- 12 DHCP Server
- 13. Network Address Translation (NAT)
- 14 Dynamic DNS
- 15. OpenDNS
- 16 Static Route
- 17.
- 17.
- 17. Routing Information Protocol
- Part III
- Part V
- Maintenance and Troubleshooting
- Part VI
- Appendices and Index
- Appendix A
- Pop-up Windows, JavaScripts and Java Permissions
- End-User License Agreement for “MWR222”
- NOTE: Some components of this product incorporate free software programs covered under the open source code licenses which allows you to freely copy, modify and redistribute the software. For at least three (3) years from the date of distribution of t...
- Notice
- Information herein is subject to change without notice. Companies, names, and data used in examples herein are fictitious unless otherwise noted. No part may be reproduced or transmitted in any form or by any means, electronic or mechanical, for any p...
- Notice
- GNU GENERAL PUBLIC LICENSE
- GNU LESSER GENERAL PUBLIC LICENSE

MWR211 User’s Guide
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When station A sends data to the AP, it might not know that the 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.
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 AP will
fragment the packet into smaller data frames.