Single-Sign-On (SSO) server with multiple factor authentication. Authentication processes supported: * OAuth2 * OpenID Connect * Allows users to authenticate via multiple factors: Password * One-time password (TOTP/HOTP) * Webauthn (Yubikey, Android devices) * One-time password sent via e-mail * TLS Certificate * Users and clients can be stored and managed from various backends: Database * LDAP service * HTTP Backend service providing Basic Authentication WWW: https://github.com/babelouest/glewlwyd