Wireless Access Point

Some might ask why you would want to build a do-it-yourself (DIY) AP when a commercially available AP often meets WLAN requirements and is affordably priced. The response to that would be flexibility and customizability. With an off-the-shelf commercial box, you are stuck with the feature-sets as offered by the AP vendor. You, therefore, have to wait for them to provide firmware upgrades to access any new functionality. In a DIY solution, you always customize the feature-set on your own.

There are at least three ways by which you can build your very own Linux-based AP. For the less adventurous, a software-only solution (e.g., Hostapd) on a vanilla Linux box is available. For the slightly more adventurous, a customized firmware implementation (e.g., OpenWRT and DD-WRT) on an existing hardware platform with a supported wireless chipset is available. And for the hardcore geeks, a customized hardware and software solution (e.g., combining a Soekris or PC Engines WRAP Board with Pyramid Linux) would get your creative juices flowing.

Hostapd This section takes a look at how you can convert a Linux box into a AP using a software-based project like Hostapd (http://hostap.epitest.fi/hostapd). The author and maintainer of the Hostapd project is Jouni Malinen.

Hostapd has a very impressive list of features that can even put some commercial solutions to shame. It not only supports WPA (IEEE 802.11i/EAP/IEEE 802.1X) features but also provides support for an integrated EAP and RADIUS authentication server within the solution. The current stable version is 0.4.9 and it supports the Prism2/2.5/3, Atheros ar521x, as well as the Prism GT/Duette/Indigo wireless chipset.

After compiling and installing Hostapd from the source code tarball, the configuration of the Hostapd daemon can be controlled via its configuration file, hostapd.conf. An example of a section of the hostapd.conf configuration file is shown here to get the hostapd daemon to perform WPA authentication using the pre-shared key:

ssid=WPA-PSK macaddr acl=1

accept_mac_file=/etc/hostapd.accept deny_mac_file=/etc/hostapd.deny auth_algs=1



wpa passphrase=passphrase wpa_key_mgmt=WPA-PSK wpa_pairwise=TKIP CCMP

After editing hostapd.conf, we will also need to create the hostapd.accept and hostapd.deny files that contain a list of MAC addresses for wireless cards that are allowed to connect to your AP. Once the configuration files are ready, you launch hostapd in the following manner (where /etc/hostapd.conf is the location of the hostapd configuration file edited earlier):

hostapd /etc/hostapd.conf

Was this article helpful?

0 0
The Ultimate Computer Repair Guide

The Ultimate Computer Repair Guide

Read how to maintain and repair any desktop and laptop computer. This Ebook has articles with photos and videos that show detailed step by step pc repair and maintenance procedures. There are many links to online videos that explain how you can build, maintain, speed up, clean, and repair your computer yourself. Put the money that you were going to pay the PC Tech in your own pocket.

Get My Free Ebook

Post a comment