Morris Winkler

Table of Contents
1. Introduction
1.1. What is OpenWrt
1.2. Copyright
2. Wireless networking.
2.1. What about Wireless
2.2. What's the max distance between radio cards?
2.3. What's the difference between wired and wireless networks?
2.4. Wireless network access modes.
2.5. Security in wireless networks.
3. Installing OpenWrt
3.1. Hardware
3.1.1. How can I identify which hardware I have?
3.1.2. Units that considered supported in the stable version (eg. known to work "out-of-the-box").
3.1.3. Additional units supported in the experimental version.
3.1.4. Units that should work. (untested)
3.1.5. Units known to not work yet.
3.2. Getting the firmware.
3.3. Installing the firmware.
3.3.1. Enabling boot_wait
3.3.2. Using boot_wait to upload the firmware
4. Using OpenWrt
4.1. Using OpenWrt for the first time
4.2. Firstboot / jffs2.
4.3. Editing Files.
4.4. ipkg
5. OpenWrt configuration.
5.1. NVRAM
5.2. Network configuration.
5.3. Wireless Configuration
5.4. Static Routes
5.5. Sample network configurations.
5.5.1. AP mode.
5.5.2. Client mode.
5.6. Finding and joining networks
6. Troubleshooting
6.1. Failsafe mode
6.2. Resetting to defaults
6.3. Recovering from bad firmware

1. Introduction

Wireless networking has been around for quit some time now, there is all kind of devices available. Bridging, routing Ad-Hoc, and whatever is out there you can buy it today . Since i and my friends used wireless networks, we where allwayes surching for a cheap way of getting professional equipment. There where people who packed 486 boxes with pcmcia2isa cardbus converters and pcmcia wireless cards in waterproof boxes and would stick them up there roof, hoping that the harddisk isn't freezing in the winter, or that the cpu run's to hot in summer. Back than outdoor router where real expensive, and so wireless community networks where growing slow. We where allwayes hoping that one day somone find's a real smart solution for that, and when i reed first time about the OpenAP project i was real happy that there is something, still it was not to easy to install OpenAP on wireless access point and the hardeware wasn't manufactured for long. So OpenAp died with the time and we where still searching for the ultimate solution, until i got first time with OpenWrt in touch, now i found this solution and with me lot's of other wireless geeking people. Anyway OpenWrt is not just usefull if you build outdoor community networks, it's so scalable that you can do allmost all with it ( have you ever seen a wireless router running OpenMosix (0_0)(0_=)(0_0).

1.1. What is OpenWrt

OpenWrt is a Linux distribution for the Linksys WRT54G. Instead of trying to cram every possible feature into one firmware, OpenWrt provides only a minimal firmware with support for add-on packages. For users this means the ability to custom tune features, removing unwanted packages to make room for other packages and for developers this means being able to focus on packages without having to test and release an entire firmware.

1.2. Copyright

Copyright (c) 2005 by Morris Winkler. This document may be distributed under the terms set forth in the LDP license at

This HOWTO is free documentation; you can redistribute it and/or modify it under the terms of the LDP license. This document is distributed in the hope that it will be useful, but without any warranty; without even the implied warranty of merchantability or fitness for a particular purpose . See the LDP license for more details.