5. Countermeasures & Conclusion

So what can you do to prevent hackers from getting into your network? Special Agent Bickers and his team have some tips for wireless users. He stresses that these are mainly for home users and should not be considered as official FBI best practices for businesses.

1) Network segregation

Put your access point on a separate subnet, with a firewall separating the wireless and internal users

2) Change the default settings on your access point

Default settings (SSID, administrator password, channel) are well known and even included as part of some WLAN attack tools

3) Use WPA with a strong key

WPA is a definite improvement over WEP in providing wireless security. But the version intended for home and SOHO use - WPA-PSK - has a weakness shared by any passphrase security mechanism. The choice of simple, common and short passphrases may allow your WPA-protected WLAN to be quickly compromised via dictionary attack (more info here).

4) Update your firmware

This is helpful if your AP or client doesn't currently support WPA. Many manufacturers have newer firmware for 802.11g products that add WPA support. You may also find this for 802.11b gear, but it's not as common. Check anyway!

5) Turn off the WLAN when not in use

A $5 lamp timer from your local hardware store is a simple, but effective way to keep your WLAN or LAN from harm while you're sleeping.

Bickers also said that if you have an access point that can swap keys fast enough, you may be able to stay ahead of an attacker. "Most likely they will get bored and attack someone else." But for most WLAN owners, this method isn't practical.

The FBI demonstrated this attack to the computer security professionals at the ISSA meeting in order to show the inadequate protection offered by WEP. It is one thing to read stories of WEP being broken in minutes, but it is shocking to see the attack done right before your eyes. It was fast and simple.

Thankfully, the FBI are the good guys.