Let's first configure our access point to use MAC filtering and then add the client MAC address of the victim laptop. The settings pages on my router looks as follows:

Once MAC filtering is enabled, only the allowed MAC address will be able to successfully authenticate with the access point. If we try to connect to the access point from a machine with a non-whitelisted MAC address, the connection will fail.

Behind the scenes, the access point is sending Authentication failure messages to the client. The packet trace resembles the following:

In order to beat MAC filters, we can use airodump-ng to find the MAC addresses of clients connected to the access point. We can do this by issuing the airodump-ng -c 11 -a --bssid <mac> mon0 command. By specifying the bssid command, we will only monitor the access point, which is of interest to us. The -c 11 command sets the channel to 11 where the access point is. The...