Hardware tokens are most basic way of authenticating.
To authenticate using a hardware token, click the Enter a Passcode button. Press the button on your hardware token to generate a new passcode, type it into the space provided, and click Log In (or type the generated passcode in the "second password" field). Using the "Device:" drop-down menu to select your token is not necessary before entering the passcode.
If you have a Yubikey token, click into the passcode entry field and tap your Yubikey to generate and submit a passcode.
Tokens can get "out of sync" if the button is pressed too many times in a row and the generated passcodes aren't used for login.
Contact the IT Security Office if your token stops working.