ESUP-OTP is a free multi-factor authentication (MFA) solution for institutions such as universities, integrated into the institution's central CAS authentication system. It consists of several components: an API (Node.js with MongoDB) that generates, sends and verifies one-time codes, a web interface where users, managers and administrators handle MFA methods and transports, a module for Apereo CAS, and the Esup Auth mobile app for push authentication. Logging in with an NFC card is available as an option.
ESUP-OTP comes from the ESUP-Portail consortium, an association under French law set up to develop open-source software for digital workspaces in higher education. The listed project partners are Université Paris 1 Panthéon-Sorbonne, La Rochelle Université and Université de Rouen Normandie. The code is released under the Apache License 2.0. Institutions run the solution on their own servers; no hosted service is described, so authentication data stays under their own control. The push app is, however, distributed through the Google and Apple app stores.