document updated 12 years ago, on Oct 16, 2011
A lot of people ask me for advice about wifi hacking. This is my attempt at a "portal" page, a page that briefly introduces the most important information you need, with links to deeper reading material elsewhere.
- radios (cards)
- unless you got lucky, you'll probably have to buy another card, since most cards don't have the proper drivers (and those drivers will probably work on Linux only, so hopefully you know Linux)
- At this point, most people ask "why?". Answer: Almost no manufacturer includes this functionality in the original driver. It only gets added by third-parties, so you either need to pay $$$ for Windows drivers, or use open source [i.e. Linux] drivers.
- aircrack's list of cards is comprehensive
- Having an antenna connector (not just an internal antenna) is a must. A good radio must be paired with a good antenna to be really effective, and if you'll ever do point-to-point, you'll want to upgrade to a directional antenna.
- I own the Alfa AWUS036H, and really like it. USB means the same card will work on laptops+desktops.
- The Ubiquiti Bullet2 is both sexy and cheap, it's by far the best outdoor solution. (img1, img2, img3, img4) (video1, video2, video3)
- antennas
- software
- Linux only, never Windows (unless you can pay $100s for commercial drivers)
- BackTrack is a great distro because it contains most third-party wifi driver patches
- you really only need to do the cracking phase once in a while; after you get the password, you can go back to your normal distro (or Windows) and use completely standard software
- tricks-n-tips
- When building your own antenna, you want to make sure that any plastic that you use in front of the antenna is RF-transparent. How do you make sure it is? Put it in the microwave and see if it gets warm!! Home microwaves use a similar frequency, so any microwave-safe plastic dishes should work well.
- Many building materials (eg. low-E thermal glass, foil-backed insulation) block wifi, so it's important to put your antenna outside.
- You really want to keep the radio and antenna as close together as possible. At higher frequencies (2.4gHz is pretty high), cable is really lossy; it's best to only use a foot or two of cable. This unfortunately* means that you really want to put a radio on your roof.
* see "cost of weatherproofing delicate electronics" above
* see also "danger of not using proper lightning protection"
- If you're feeling really ambitious, you also want to mount your antenna as high as possible.
