Keycloak

Master enterprise identity and access management with the powerful open-source IAM solution

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What is Keycloak?

Keycloak is an open-source Identity and Access Management (IAM) solution that provides user authentication, authorization, and user management for modern applications and services. It eliminates the need to store or authenticate users in applications by providing single sign-on (SSO), identity brokering, social login, and user federation capabilities.

Created by Red Hat and part of the WildFly application server ecosystem, Keycloak supports standard protocols like OAuth 2.0, OpenID Connect (OIDC), and SAML 2.0. It provides a complete solution for securing applications, APIs, and microservices with features like multi-factor authentication, password policies, and fine-grained authorization.

Keycloak Capacity Calculator

2612MB
Memory Required
550ms
Avg Login Time
500
Max Sessions
95%
Availability

CPU Cores: 2

DB Storage: 10GB

Security Score: 85/100

Keycloak Core Components

Realms

Isolated spaces for managing users, roles, and applications.

• Complete isolation
• Separate user stores
• Independent configurations
• Multi-tenant support
• Cross-realm trusts

Clients

Applications that request authentication from Keycloak.

• Web applications
• Mobile apps
• API services
• Public/confidential types
• Protocol mappers

Users & Groups

User accounts and organizational structures.

• User accounts
• User attributes
• Group hierarchies
• Group membership
• Federated users

Roles & Permissions

Authorization and access control mechanisms.

• Realm roles
• Client roles
• Composite roles
• Role mappings
• Fine-grained permissions

Keycloak Authentication Features

Single Sign-On (SSO)

Users authenticate once and gain access to multiple applications.

1. User accesses Application A
2. Redirected to Keycloak for authentication
3. User provides credentials and authenticates
4. User accesses Application B
5. Automatically authenticated (SSO session exists)
6. User gains access without re-entering credentials

Multi-Factor Authentication

• TOTP (Time-based OTP)
• SMS authentication
• Email verification
• Hardware tokens
• Biometric authentication
• Conditional MFA

Social Login

• Google OAuth
• Facebook Login
• GitHub authentication
• LinkedIn login
• Custom identity providers
• Account linking

User Federation and Identity Brokering

LDAP/Active Directory

Connect to existing enterprise user directories.

• LDAP v3 support
• Active Directory integration
• User synchronization
• Group mapping
• Attribute mapping
• Password delegation

Custom Providers

Integrate with custom user stores and systems.

• Custom User SPI
• REST API integration
• Database connections
• Legacy system integration
• Custom authentication
• Migration support

Identity Brokering

Delegate authentication to external identity providers.

• SAML 2.0 providers
• OpenID Connect providers
• Token exchange
• Account linking
• First login flows
• Trust relationships

User Storage

Flexible user storage and management options.

• Local database
• Federated storage
• Read-only sources
• Caching layers
• Offline users
• Import strategies

Protocol Support and Integration

OpenID Connect

Modern authentication protocol built on OAuth 2.0.

• Authorization Code Flow
• Implicit Flow
• Hybrid Flow
• Client Credentials
• JWT tokens
• Dynamic registration

SAML 2.0

Enterprise standard for federated identity.

• Identity Provider (IdP)
• Service Provider (SP)
• Metadata exchange
• Assertion encryption
• Attribute statements
• Single logout

OAuth 2.0

Authorization framework for API access.

• Access tokens
• Refresh tokens
• Scope management
• Client authentication
• PKCE support
• Token introspection

Real-World Keycloak Implementations

European Central Bank

Uses Keycloak for secure access to financial systems and regulatory compliance.

  • • Multi-factor authentication
  • • Regulatory compliance
  • • Federated identity
  • • Audit logging

Lufthansa

Leverages Keycloak for employee and customer identity management across systems.

  • • Employee SSO
  • • Customer portals
  • • Mobile applications
  • • Partner integrations

MIT

Uses Keycloak for academic and research platform authentication.

  • • Student authentication
  • • Research platform access
  • • LTI integration
  • • Federated research

Bosch

Implements Keycloak for IoT device authentication and industrial applications.

  • • IoT device authentication
  • • Industrial applications
  • • Supply chain systems
  • • Partner ecosystems

Keycloak Best Practices

✅ Do

  • • Use HTTPS for all Keycloak communications
  • • Implement proper backup and disaster recovery
  • • Configure strong password policies
  • • Enable audit logging and monitoring
  • • Use realm separation for multi-tenancy
  • • Implement MFA for administrative accounts
  • • Regular security updates and patches

❌ Don't

  • • Use default credentials in production
  • • Skip SSL/TLS configuration
  • • Ignore performance tuning for large deployments
  • • Store sensitive data in custom attributes
  • • Bypass security policies for convenience
  • • Neglect database security and backups
  • • Mix development and production realms

📝 Keycloak Quiz

1 of 6Current: 0/6

What is Keycloak primarily used for?