Building a Wireless Access Point on Linux

By Peter Seebach
2005-04-12


Requirements
The computer I used for this project is a Soekris net4521 embedded system. The CPU is a 133Mhz 486-class processor; plenty of power. The OS gets loaded on a CompactFlash (CF) card. I needed a wireless adapter; I grabbed a cheap LinkSys WPC11, based on the Intersil Prism 2 chipset. Similar systems would work as well.

To follow the whole thing, you'll also need another Linux box, to format and configure the flash card. A laptop is ideal, but anything with a USB port should work, if you have a CF reader that works under Linux.

As for software, there are existing packages that come pretty close to working out of the box, or you could start from scratch with an old set of install CDs and do it the hard way. For this article, I started with Pebble Linux, a small distribution that comes close to meeting my needs right off the bat. However, there's plenty of fun to be had tweaking settings and maybe adding a few custom features. From here on in, I'll be assuming you've got basic experience using Linux: editing files, running commands, and maybe even configuring a simple network. If you don't, your friendly neighborhood Linux hacker will probably walk you through this project for the price of a pizza, and explain what's going on if you include extra cheese.

For this project I used 802.11b wireless, the standard used by Apple's original Airport network and the most widely-available wireless standard. Theoretical bandwidth is 11Mbps, or just a tad faster than slow ethernet. The practical bandwidth is good enough to keep up with cheap broadband. The reception range is variable, but most people can reach a back yard or a neighboring apartment.

Tutorial Pages:
» Custom Solution Offers Flexibility and Customizability -- and a Chance to Learn
» Why bother?
» Requirements
» Project Plan
» Conclusions
» Resources


First published by IBM DeveloperWorks

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