This document lists the advantages and considerations for using some of the Duo options to help you choose the ones that will work best for you.
Be sure to set up a backup option if you haven’t done so already. See Options for Two-Factor Authentication for descriptions of all the options with links to enrollment procedures.
Duo Mobile app 
Advantages
✔️ Offers multiple login-approval methods (passcode, push notification; phone call and text message when installed on a smartphone).
✔️ Works with or without a WiFi or cellular connection.
✔️ Likely always with you because it is stored on your smartphone or tablet.
✔️ Works with Apple Watch and Android smartwatch.
✔️ When traveling internationally, most people can use the Duo Mobile app to generate a passcode because it works without a WiFi or cellular connection.
Considerations
◼️ Requires a smart device.
Text message 
Advantages
✔️ Each text message contains 10 passcodes that are good for 30 days.
Considerations
◼️ Requires a WiFi or cellular connection to receive a text message; standard text message rates apply.
Hardware token 
Advantages
✔️ Key fob is small and easily attached to a keychain, backpack, and so on.
✔️ Available at no cost to individuals from the Tech Shop.
Considerations
◼️ May be lost or misplaced. You are responsible for the cost if you want a replacement.
YubiKey 
Advantages
✔️ Fits in the USB port of your computer, so login is quick and easy. Just touch the YubiKey.
✔️ Available at no cost to individuals from the Tech Shop.
Considerations
◼️ Takes up USB slot.
◼️ Not a good option if you use multiple computers.
Phone call 
Advantages
✔️ You can use any of your phone numbers, such as your personal home phone or cell phone.
Considerations
◼️ Requires a phone—landline or cellular; standard phone rates apply.