You don’t want to dink around with prefab commercial wireless access points. They’re either too simple and too inflexible for your needs, or too expensive and inflexible. So, like a good Linux geek, you want to build your own. You want a nice quiet little compact customizable box, and you want to be able to add or remove features as you need, just like on any Linux computer. For starters, you want everything on a single box: authenticated wireless access point, broadband Internet connection sharing, iptables firewall, and name services.
Install Pyramid Linux on a Soekris or PC Engines WRAP single-board computer.
Install an Atheros-based wireless mini-PCI card and connect an external antenna.
Configure and test LAN connectivity, and DHCP and DNS.
Keep your router off the Internet until it’s properly hardened, firewalled, and tested.
Add Internet connectivity, and voilà! It is done.
Continue on to the next recipes to learn how to do all of these things.
If you prefer separating out your services on different physical boxes, such as wireless access point, firewall, and nameserver, the recipes in this chapter are easy to adapt to do this.
Soekris has two series of routerboards: 45xx and 48xx. Choose whatever model meets your needs. At a minimum, you need 64 MB RAM, a Compact Flash slot, a mini-PCI slot, and two Ethernet ports. More powerful CPUs and more RAM are always nice to have. A second mini-PCI slot lets you add a second wireless interface. PCMCIA slots give you more flexibility because these support both wired and wireless interfaces.
The 45xx boards have 100 or 133 MHz CPUs and 32 to 128 MB SDRAM. The 48xx boards have 233 or 266 MHz processors and 128 to 256 MB SDRAM. You’ll see network speeds top out on the 45xx boards around 17 Mbps, and the more powerful 48xx boards will perform at up to 50 Mbps. 17 Mbps is faster than most cable or DSL Internet connections. For ordinary web surfing and email, the 45xx boards are fine. If you’re running VoIP services, doing online gaming, serving more than 50 users, or running any peer protocols like BitTorrent, then go for the 48xx boards.
PC Engines WRAP boards are similar to the Soekris boards, and are usually a bit less expensive. Both use Geode CPUs, are about the same size, and similarly featured. Both vendors will customize the boards pretty much however you want.