Keycloak
Keycloak is an open-source IAM server providing single sign-on, user federation, and centralized authentication and authorization using OIDC, OAuth 2.0, and SAML.

Keycloak is an open-source Identity and Access Management (IAM) server for modern applications and services. It centralizes authentication and authorization so applications can rely on standards-based SSO instead of implementing login, user storage, and session management.
Key Features
- Single sign-on and single sign-out across multiple applications
- Support for standard protocols: OpenID Connect, OAuth 2.0, and SAML 2.0
- Identity brokering and social login via configurable identity providers
- User federation with LDAP and Active Directory, with extensible provider support
- Admin console for managing realms, clients, users, roles, sessions, and policies
- Account management console for end users (profile, password changes, session management, and 2FA)
- Fine-grained authorization services for policy-based access control
Use Cases
- Centralized SSO for internal apps, APIs, and microservices
- Replacing custom authentication with standards-based identity and token issuance
- Integrating enterprise directories (LDAP/AD) and external identity providers into one login flow
Limitations and Considerations
- Operating securely at scale requires careful configuration of realms, clients, token lifetimes, and session settings
- Some advanced deployments may require external databases and clustering planning for high availability
Keycloak is widely used as a central identity provider to standardize authentication and access control across heterogeneous systems. It reduces application complexity while enabling consistent security policies and user management in one place.















