How Can I Use DUO While Traveling Internationally? When traveling outside of the United States, you may not be able to use cell service on your cell or smartphone. In this situation, you can use the Duo App on your smartphone, a key fob or an internet-based phone number installed on your laptop. We briefly describe each scenario in this section. If you have a smart phone, the easiest option is to install the DUO Mobile app then use it to generate passcodes when you have to authenticate. This is outlined in step 1 below.
Use the DUO Mobile app on your smartphone or tablet to generate passcodes.
Prior to travel, install the Duo mobile app on your smartphone or tablet.
If you need to authenticate while traveling, you can click the "Enter a passcode" link on the login screen. On your smartphone or tablet, start the Duo Mobile app, and click on the "key" button. This will display a passcode that you type into your computer to authenticate. No Cell or Wi-Fi signal is needed to use this option.
Use a key fob.
Prior to travel, you can order a key fobthrough the ASU bookstore. Prices are displayed on the bookstore website. To use the keyfob when you need to authenticate, click on the "Enter a Passcode" link on your computer. On your keyfob, click the button. A passcode will appear on the fob. Enter that number into the computer and click "login". No Cell or Wifi signal is needed to use this option.
Use an internet-based phone number.
Prior to travel, sign up for an Internet based phone number. Google Voice is an example. Once you have a number, you can enroll it in the DUO Mobile app and use the number on your computer, smartphone or tablet. To authenticate, use the "call me" feature. Note that a Wifi signal is needed for this option to work.
Use international numbers
Duo will work with international numbers but the text options may be restricted due to the regulations of the country. We suggest using the phone call or DUO push options. You can enter your international phone number with the E.164 format: plus sign “+”, country code after removing any “0” digits at the prefix, group or national code and subscriber number.
Let’s take England for example. The country code is +44 and the number locally in England is 07911-123456. This would result in the following number: +447911123456
Note that you will be charged for call and data rates in accordance with your cell carrier plan.