yubikey

defguard is an SSO & VPN Server based on OpenID and WireGuard VPN with unique secure & private architecture for building secure and privacy-aware organizations.

Okta's Workforce and Customer Identity Clouds enable secure access, authentication, and automation—putting identity at the heart of business security and growth.

OnlyKey is an open source alternative to YubiKey. OnlyKey natively supports: a hardware password manager, multiple two-factor methods (FIDO2, TOTP, and Yubico® OTP), passwordless SSH login, and OpenPGP.