Edimax Technology BR-6574n - Manual (Page 93)

3-4-1-7 Set Security
In certain AP working modes, you can enable encryption to improve
security level.
When you click ‘Set Security’ button, the following window will appear:
Please select an encryption method from ‘Encryption’ dropdown menu,
and corresponding setting will appear:
Disabled
Encryption is disabled. It’s not recommended to disable encryption
because other people may use certain wireless scanner to copy the data
transferred over air.