Duo Mobile
Overview
For improved security, Campus IT requires a 2nd form of authentication every time you log in with your directory ID and password. For this 2nd form of authentication, you can get a phone call from your desk phone or a phone call from your cell phone, type in a random code from a hardware token or approve the login attempt from your Duo Mobile app.
You can follow the article "Set your default Multi-Factor Authentication Device" from DIT for help downloading and setting up Duo for the first time. The link also includes instructions for adding new Duo devices, removing old ones, and managing your preferences.