Decrypting wireless network traffic

Wireshark also facilitates decryption of wireless traffic through embedding a pre-shared key under the 802.11 protocol section. The following screenshot depicts normal wireless traffic being sniffed from a nearby access point:

WLAN traffic before decryption

In order to decrypt the preceding listed packets, we need to configure the IEEE 802.11 section as follows:

1. Go to Edit | Preferences, expand the Protocol section, select IEEE 802.11 and configure it as follows:

2. Click on the Edit button next to Decryption Keys.
3. Click on New and add the WEP/WPA key to enable decryption. After all the changes have been made, click on OK:

Now you will be shown the decrypted traffic as follows:

WLAN traffic after decryption