Topics Map > University of Chicago > IT Services > Accounts, Identity, & Security

2Factor Authentication (2FA) - Using Passcodes without Phone Data Connection

This article explains how to retrieve passcodes from Duo that can be used in case one cannot use their cellphone's data connection to authenticate but still wants to access services protected by 2FA.

A helpful feature of Duo is that it can be used to access Shibbolized UChicago sites using 2FA without data network access, using generated passcodes instead of push notifications. This feature is useful if you would like to access UChicago sites, but you have unreliable or costly access to data services on your mobile phone. Some examples might include if you are traveling abroad, in remote areas with intermittent cell reception, or on an airplane. There are two ways to generate passcodes:

  • If you plan on having your mobile phone with you, you can use the passcode feature on the Duo mobile app. To use, simply open the app and press the key icon in the upper right hand side of the app for iOS and Android or the Generate Passcode button on Microsoft OS devices.  A six-digit numeric code is generated that can be entered when a UChicago site requests Two-Factor Authentication. This feature does not use any data services, and can be used with or without Internet access on your mobile phone. It can be used as many times as you would like.


  • Alternatively, if you think you may not have access to your mobile phone at all, you can use the Text Passcodes service. To use this service, before you leave, log on to the 2FA site at 2fa.uchicago.edu. Navigate to the Manage Devices section, and find your device. Click on Text Passcodes.


    A list of ten one-time-use passcodes will be sent to your device via text. You may then write down or print the codes if you do not think you will have access to your device. These codes are single use; therefore, it is important to keep track of which codes you have already used. A code can be entered when a UChicago site requests Two-Factor Authentication. Be sure to keep this list in a secure location, although even if the passcodes are lost, your account is still protected by your password. This service does require data usage when initially retrieving the passcode list, but once you have the list a mobile device is not required.



Keywords:"two factor authentication" shibboleth data passwords duo   Doc ID:57014
Owner:William M.Group:University of Chicago
Created:2015-10-05 14:18 CSTUpdated:2015-11-05 12:24 CST
Sites:University of Chicago, University of Chicago - Sandbox
Feedback:  0   0