Carla Schroder

The RADIUS (Remote Authentication Dial-In User Service) protocol has long been a standard authentication, authorization and accounting protocol for Internet service providers and businesses. It determines who you are, what you’re allowed to do, and records how long you did it for. It works for more than just dialup users- it also works for DSL, […]

For ultimate control and customizability, building your own Linux wireless access point is the way to go. You may use an old recycled PC, or build a sleek attractive power- and space-saving unit from new parts. It may save a small pot of money, because you’ll end up with a WAP that can do anything […]

In the first three parts of this series we have wandered widely over the whys, wherefores, and hows of voice over Wi-Fi. Today we’re wrapping up our VoIP Wi-Fi phone overview with a look at multi-mode portable devices: combination cell phones/Wi-Fi phones/Web browsers/PDAs/kitchen sink devices that fit in a pocket. Sometimes a large pocket, but […]

Now that we have thoroughly dissected the pros and cons and technological challenges of extending VoIP services to Wi-Fi in part 1 and part 2 of this little series, let’s take a look at VoIP/Wi-Fi in action. Wi-Fi phones Back in my grandmother’s day getting a telephone was easy. There was but one phone company, […]

Wireless security protocols have improved considerably, despite the lackadaisical attitude of most users towards their computer security. This is shocking I know, but remember these are the same people who never lock their doors, leave their keys in the car, and dump their kids on random strangers to babysit. But for those of us who […]

In last week’s installment, we installed DD-WRT on a Buffalo wireless broadband router. Today we’re going to learn how to do package management, TurboBoost, access restrictions and WPA/WPA2 authentication and encryption. While you’re still getting your router configured, don’t connect its WAN port to the Internet; it’s not ready for that yet. It’s better to […]

The popular DD-WRT project was initially an offshoot of the original Linksys firmware for the WRT54, but has since undergone a complete rewrite, and now uses the OpenWRT kernel. DD-WRT is a fine upgrade for your WRT54 wireless router, or any similar device under other brand names, and there are a lot of them. The […]

Last week we learned how to use iperf to measure network throughput, jitter, and datagram loss. Today we’re going to learn more excellent ways to measure network performance using iperf and ntop, but first I have a couple of corrections to make. OpenWRT, Little Blue Boxes, and Heavy Loads In Tips and Tricks for Linux […]

Last week we learned some fun ways to mess with the minds of wireless freeloaders, and introduced ourselves to some methods for finding out who is on our networks. Today we’re going to learn some different ways to kick unwanted visitors off networks, and how to see exactly who is lurking on our airwaves. Killing […]

A lot of folks have an unhealthily casual attitude towards securing their wireless networks. “Oh, it’s nice to share” some say. Others think “I have nothing to interest a cracker, so why bother?” Both attitudes are inviting trouble. There is nothing to be gained from leaving your systems open to be used as warez, porn […]

In our previous installments we got our little Soekris board up and running, installed Pyramid Linux, and built a nice stout iptables firewall. Today we’ll build a wireless access point, so that you can have both wired and wireless clients on your LAN. Some security-conscious admins prefer using a standalone WAP, rather than combining it […]

In the first two parts of this series we took a tour of the Soekris 4521 single-board computer and installed the Pyramid Linux operating system. Now it’s time to build a good stout iptables firewall. Just Say No To Lard When you’re used to hacking on old PCs it’s easy to fall into bad habits, […]