
Here's quick way check the encryption of your WiFi connections:
1 - Open your terminal in Linux and run the following command:
Find the ID for your wireless adapter, run ifconfig, scroll down until you see WLAN followed by number. Most of the time it would be wlan0


3 - Here's example of what it must look like for you to know you've got a secure connection:

- Encryption key: on << this is probably the first thing you must look for :)
- WPA2 is the standard that replaced WEP. This is the recommended security protocol for wireless communication.
- TKIP is the encryption method used in WPA (WiFi protected areas), which replaced WEP in WLAN products.
- CCMP is the standard encryption protocol for use with the WPA2 standard
- PSK is a shared secret between two parties using secure channel
Hope this works for you. It helps me know how careful I must be when using open networks.