If you don't have a smartphone and you travel internationally often, you have an option of obtaining a hardware token to authenticate. Contact the IT Service Desk at 978-934-4357 or email: help@uml.edu to request a token. You will be required to visit the IT Service Desk to obtain the token and start the registration process.
To authenticate via the hardware token, simply choose the "Enter the Passcode" option when you get the Duo authentication prompt and then enter the passcode that is displayed on the hardware token.