RajeshKumar1 Here’s a list of open-source Single Sign-On (SSO) solutions available: 1. Keycloak Description: An open-source Identity and Access Management (IAM) solution developed by Red Hat. Features: Supports OAuth 2.0, OpenID Connect, SAML, LDAP, Active Directory integration, multi-tenancy. GitHub: Keycloak Repository 2. Gluu Server Description: An enterprise-ready open-source IAM solution that supports OAuth 2.0, OpenID Connect, and SAML. Features: Strong authentication, adaptive authentication, support for multi-factor authentication (MFA). Website: https://gluu.org/ 3. Authelia Description: A modern authentication and SSO server designed for secure access to web applications. Features: Supports 2FA, OpenID Connect, LDAP, proxy authentication. GitHub: Authelia Repository 4. LemonLDAP::NG Description: A modular authentication and access management web SSO solution. Features: Supports LDAP, SAML, OpenID Connect, CAS, MFA. GitHub: LemonLDAP Repository 5. WSO2 Identity Server Description: A robust IAM solution that supports SAML, OpenID Connect, and OAuth. Features: API security, multi-factor authentication, user federation. Website: https://wso2.com/identity-server/ 6. CAS (Central Authentication Service) Description: A widely used authentication system originally developed by Yale University. Features: Supports SAML, OpenID Connect, OAuth, MFA. GitHub: CAS Repository 7. ORY Hydra Description: A lightweight OAuth 2.0 and OpenID Connect authentication server. Features: Designed for microservices, Kubernetes-friendly, secure OAuth implementation. GitHub: ORY Hydra Repository 8. FusionAuth (Community Edition) Description: A developer-friendly authentication and IAM solution. Features: Multi-tenant support, passwordless authentication, SAML, OpenID Connect. Website: https://fusionauth.io/ 9. OpenIAM Description: A full-featured IAM platform for authentication, authorization, and user management. Features: SSO, multi-factor authentication, user provisioning. Website: https://www.openiam.com/ 10. OpenUnison Description: An open-source identity gateway that supports SSO. Features: Supports LDAP, SAML, OpenID Connect, MFA, Kubernetes integration. GitHub: OpenUnison Repository 11. SimpleSAMLphp Description: A PHP-based implementation of SAML for authentication and SSO. Features: Identity provider (IdP) and service provider (SP) support, LDAP integration. GitHub: SimpleSAMLphp Repository Would you like any specific recommendations based on your use case?