Duo Security - Duo Security provides cloud-based two-factor authentication. Duo’s technology can be deployed to protect users, data, and applications from breaches, credential theft, and account takeover.
Authy - Best rated Two-Factor Authentication smartphone app for consumers, simplest 2fa Rest API for developers and a strong authentication platform for the enterprise.
Protectimus - Protectimus multi-factor authentication solution is powerful and flexible, and scales to meet the needs of any business
LoginTC - Simply Strong Two-Factor Authentication LoginTC is best in class. Effortless Administration. Intuitive User Experience. Cost-effective solution for all organizations.
DIGIPASS - DIGIPASS offers two-factor authentication solutions for mobile applications.
Yubico - YubiKey provides security solutions for strong two-factor authentication using U2F, OTP, PIV, and more.