GET A HANDLE ON MONITOR MODE

So what’s all the fuss about using an additional Wi-Fi card? In short, there are several modes that are potentially available on network cards. These modes include Monitor, Infrastructure, Mesh, and Managed, as well as a few others. Most of the time, users don’t have to understand or make use of the modes. As a result, the hardware manufacturers don’t spend much effort on making cards that work well with Monitor mode.

While putting this article together, it took several attempts to find a USB card that works for Raspbian. It’s possible to find out which modes your network card works with using the command

iwconfig info wlan0 (or other wireless interface). This will give various groups of information, including details on supported modes. By default, Kismet configures the network card to use Monitor mode, so it doesn’t have to be manually set.

It is, however, possible to make the card manually switch into Monitor mode by using the following commands:

sudo if down wlan1 sudo iwconfig wlan1 mode Monitor sudo ifup wlan1

As previously noted, if you do this, the network will stop responding if you use it on the network interface you’re connected through. It’s set to passively monitor and report all networks it sees. The wireless card used in this tutorial was a TP-LINK TL-WN727N, purchased online for about $17. Do be sure to check its specs, though—there are a lot of similar cards that don’t work.