# Top 7 Open Source Keycloak Alternatives

# Outline

## Introduction
A brief introduction on keycloak, and mentioning the rising demand for open-source identity and access management (IAM) solutions.
Purpose of the article is to explore top open-source alternatives to Keycloak and discuss their key features, strengths, and potential drawbacks.

## What is Keycloak?
A brief overview of Keycloak and its functionalities.
How Keycloak works.

## Top Open-Source Keycloak Alternatives
This section would discuss on the following; Overview of the platform and its core functionalities, strengths and advantages compared to Keycloak (e.g., specific features, ease of use, etc.), potential drawbacks or limitations. and Ideal use cases for this alternative.

1. ORY Hydra
2. Apache Syncope
3. Gluu Server
4. WSO2 Identity Server
5. LemonLDAP::NG

## A Comparison Table Between Keycloak and Other Alternatives
A table summarizing the key features, supported protocols, deployment options, and community aspects of each alternative.

## Key Considerations When Choosing a Keycloak Alternative
Factors to consider when making a decision such as; Project size and complexity, required features and functionalities, deployment preferences (cloud vs. on-premise), and technical expertise and available resources.

### Conclusion
A recap on the importance of open-source IAM solutions and the diverse options available.
Reiterate that the best choice depends on specific needs and requirements.
Encourage readers to check out Permify.

### Additional Resources
Links to the official websites, documentation, and community forums of each alternative.
Other relevant resources on open-source IAM solutions.

------------------------------------------------------------

# DRAFT
## Introduction
If you have a robust application, you will agree that securing sensitive data and managing user access is paramount. For this reason, ***Keycloak*** an open-source Identity, and Access Management (IAM) solution, has gained widespread popularity for its comprehensive features and ease of use.

Like any other technology, there are often alternative options that cater to specific needs and preferences. This article aims to discuss the various open-source Keycloak alternatives, highlighting seven prominent strong contenders in the IAM space.

We'll explore their key features, pros, cons, and ideal use cases to help you make an informed decision based on your project requirements.

Table of Content
* What is Keycloak? A Brief Overview
* Top 7 Open Source Keycloak Alternatives
* A Comparison Between Keycloak Vs Other Open Source Alternatives
* Factors to consider When Choosing Keycloak Open Source Alternative
* Conclusion

## What is Keycloak? A Brief Overview
This is an open-source identity and access management solution that provides a centralized platform for managing user identities and controlling access to applications and services.
Keycloak handles user logins, authorization rules, and user management by acting as a central authentication and authorization server.

### Keycloak Features and Functionalities
Keycloak offers a broad spectrum of features that support secure identity management and access control:

1. **Single Sign-On (SSO):** It provides SSO capabilities, allowing users to authenticate once and gain access to multiple applications without repeatedly logging in.
2. **Identity Brokering and Social Login:** It supports various external identity providers like Google, Facebook, and Twitter, enabling seamless social logins.
3. **User Federation:** Keycloak can federate user identities across multiple data sources such as LDAP and Active Directory.
4. **OAuth2.0, OpenID Connect, and SAML Support:** It uses to industry-standard protocols for authentication and authorization.
5. **User Management:** Administrators can manage users, roles, and groups through an intuitive admin console, simplifying the user lifecycle management process.
6. **Customizable Authentication Flows:** It allows for the creation of custom authentication flows to cater to specific security requirements.
7. **Multifactor Authentication (MFA):** Keycloak supports MFA, adding another layer of security to the authentication process.
8. **Extensible and Integrable:** It can be extended with custom code and integrated with existing infrastructure through APIs and service hooks.

### How Does Keycloak Work?
Keycloak secures applications and manages user interactions by leveraging industry-standard protocols like OpenID Connect and OAuth 2.0.

Here's a breakdown of how it works:

**User Authentication:** When a user tries to access a protected resource (e.g., a web application), they are redirected to the Keycloak server for authentication.
**Credentials Validation:** Keycloak verifies the user's credentials (username/password, social logins, MFA) against its user database or external identity providers.
**Access Control:** Based on the user's authentication and assigned roles, Keycloak determines their access privileges to the resource.
**Token Issuance:** If authorized, Keycloak issues a secure token (JSON Web Token - JWT) containing user information and permissions. This token is sent back to the application.
**Resource Access:** The application then verifies the token's validity and uses the encrypted information to grant the user access to the requested resource.

This process streamlines user authentication, simplifies access management, and enhances security by centralizing control over user identities and permissions.

## Top 7 Open Source Keycloak Alternatives

### 1. [Zitadel](https://zitadel.com)

Zitadel is a modern, cloud-native identity and access management solution designed for microservices architectures. It emphasizes strong security, scalability, and developer-friendliness.

#### Key Features of Zitadel
* **Multi-tenancy:** It allows for managing multiple independent organizations within a single instance.
* **Web Single Sign-On (SSO):** It allows users to access multiple web applications with a single login.
* **Multifactor Authentication:** It offers MFA with OTP, U2F, Email OTP, and SMS OTP.
* **Support for Various Protocols:** It supports popular authentication protocols, like SAML2, OpenID Connect, and OAuth 2.0.
* **Centralized User Management:** It provides a single point of control for managing user accounts, roles, and permissions.
* **Fine-Grained Authorization:** Enables granular access control based on user roles, policies, and resource permissions.

#### Pros
* **Microservices Architecture:** Built with microservices in mind, this makes it highly scalable and flexible.
* **Strong Security Focus:** It has a built-in multi-factor authentication, audit logging, and data encryption.
* **Developer-Friendly APIs:** It has a well-documented REST APIs and SDKs for easy integration with applications.

#### Cons
* **Relatively New:** Compared to established solutions like Keycloak, Zitadel has a smaller community and fewer out-of-the-box features.
* **Steeper Learning Curve:** While the APIs are well-documented, its architecture may require more technical expertise for setup.

#### Ideal Use Cases for Zitadel
* For microservices environments that require secure, and scalable identity management.
* For applications demanding flexible integration and customization.

### 2. [Apereo CAS](https://apereo.github.io/cas/7.0.x/index.html)

Known for its stability, extensive feature set, and support for various authentication protocols. Apereo CAS is a mature and widely adopted open-source single sign-on (SSO) solution.

#### Key Features of Apereo CAS
* **Single Sign-On (SSO):** Enables users to access multiple applications with a single login.
* **Multi-Factor Authentication (MFA):** Enhances security by requiring users to provide multiple forms of authentication.
* **User Provisioning:** Supports synchronizing user accounts across various systems.
* **Multi-Protocol Support:** Supports various authentication protocols, including SAML, OAuth 2.0, and OpenID Connect.
* **Extensive Customization Options:** Offers a high level of flexibility and customization to meet specific needs.

#### Pros
* **Mature and Stable:** Long-standing project with a large community and extensive documentation.
* **Extensive Features:** Supports SSO, multi-factor authentication, user provisioning, and various authentication protocols (e.g., SAML, OAuth 2.0).
* **Widely Used:** Used by many universities, institutions, and organizations.

#### Cons
* **Can Be Complex:** The configuration and setup process can be more complex compared to simpler solutions.
* **Less Modern Interface:** The interface may not be as modern or user-friendly as some newer alternatives.

#### Ideal Use Cases for Apereo CAS
* Large institutions, universities, and organizations who need robust SSO and user management.
* Environments with legacy systems and diverse authentication protocols.

### 3. [Apache Syncope](https://syncope.apache.org/)

This is a comprehensive open-source identity management solution that combines user provisioning, governance, and access management. It focuses on providing a centralized platform for managing user identities across various systems.

#### Key Features of Apache Syncope
* **Centralized User Repository:** It provides a single source of truth for managing user accounts, roles, and groups.
* **User Provisioning and Synchronization:** It supports connecting to various systems and automating user account creation, updates, and deactivation.
* **Identity Governance:** It includes features for managing user access policies, enforcing access control rules, and auditing user actions.
* **Workflow Management:** It provides tools for automating user account management processes and approval workflows.
* **Multi-Protocol Support:** It integrates with various protocols, including LDAP, Active Directory, and OpenID Connect.

#### Pros
* **Centralized User Management:** Provides a single point of control for managing user identities and access rights.
* **Extensive User Provisioning:** Supports various connectors to synchronize users and groups across different systems.
* **Strong Governance Features:** Includes features for enforcing access policies, auditing user actions, and managing password complexity.

#### Cons
* **Complex Setup:** This can be more challenging to set up and configure compared to simpler solutions.
* **Steeper Learning Curve:** Requires more technical expertise to fully leverage its capabilities.

#### Ideal Use Cases for Apache Syncope
* Organizations with complex user environments and need for centralized identity management.
* Environments where user provisioning and governance are critical.

### 4. [LemonLDAP::NG](https://lemonldap-ng.org/documentation/latest/)

LemonLDAP::NG is an open-source solution that offers a flexible and customizable approach to authentication and authorization, which is primarily focused on web Single Sign-On (SSO). Making it well-suited for smaller environments or projects that demand high customization.

#### Key Features of LemonLDAP::NG
* **Web Single Sign-On (SSO):** It enables users to access multiple web applications with a single login.
* **Multi-Factor Authentication (MFA):** It supports various MFA methods to enhance security.
* **Customizable Authentication Flows:** Allows for defining custom authentication flows based on specific needs.
* **Flexible Configuration:** It offers extensive configuration options to tailor the solution to various environments.
* **Support for Various Protocols:** It supports popular authentication protocols, including SAML, OpenID Connect, and OAuth 2.0.

#### Pros
* **Lightweight and Flexible:** Offers a simpler and more lightweight approach to SSO compared to heavier solutions.
* **Highly Customizable:** Allows for extensive configuration and customization to fit specific needs.
* **Strong Security Focus:** Implements strong security practices and supports multi-factor authentication.

#### Cons
* **Limited Feature Set:** Offers a more focused feature set compared to more comprehensive IAM solutions.
* **Steeper Learning Curve for Customization:** Requires technical expertise to configure and customize effectively.

#### Ideal Use Cases for LemonLDAP::NG
* Smaller organizations or projects that require web SSO but don't need extensive IAM capabilities.
* Environments requiring high levels of customization and control over authentication and authorization.

### 5. [WSO2 Identity Server](https://wso2.com/identity-server/)

WSO2 Identity Server is a comprehensive IAM solution that focuses on scalability and advanced features for enterprise-grade platforms. By offering a wide range of features for managing user identities, access rights, and policies.

#### WSO2 Identity Server Key Features
* **Scalable and Secure IAM Platform:** It is built to handle large user bases and complex identity management scenarios.
* **Entitlement Management:** Allows for managing and enforcing fine-grained access controls based on user roles, policies, and permissions.
* **Identity Governance:** It provides tools for managing user identities, roles, and access privileges.
* **Identity Analytics:** It offers features for analyzing user activity, identifying security risks, and improving compliance.
* **Extensive Integration:** It supports integration with various systems, protocols, and applications.

#### Pros
* **Scalable Architecture:** Designed to handle large user bases and complex identity management scenarios.
* **Advanced Features:** Includes features like entitlement management, identity governance, and analytics.
* **Strong Customization:** Offers a high degree of customization and flexibility.

#### Cons
* **Complex Setup and Configuration:** Requires significant technical expertise to set up and manage.
* **Enterprise-Focused:** Can be overkill for simpler use cases and may be more expensive than alternative solutions.

#### Ideal Use Cases for WSO2 Identity Server
* Large enterprises with complex identity management needs and demanding security requirements.
* Organizations requiring advanced features like entitlement management and governance.

### 6. [Gluu Server](https://gluu.org/)

Gluu Server is a full-fledged open-source IAM solution that provides a comprehensive set of features for identity management, access control, and authentication. It emphasizes standard compliance and offers a wide range of deployment options.

#### Key Features of Gluu Server
* **Comprehensive Identity Management:** Provides a comprehensive suite of features for managing user identities, access rights, and policies.
* **Standards Compliance:** Adheres to industry standards, ensuring interoperability with other systems and applications.
* **Multi-Protocol Support:** It supports various authentication protocols, including OpenID Connect, OAuth 2.0, and SAML.
* **Flexible Deployment Options:** It allows for deployment on-premise, in the cloud, or in a hybrid environment.
* **Advanced Features:** It includes features like user provisioning, access control, authorization, and identity governance.

#### Pros
* **Comprehensive Feature Set:** Offers a broad range of features, including SSO, MFA, user provisioning, and access management.
* **Standards Compliance:** Adheres to industry standards like OpenID Connect, OAuth 2.0, and SAML.
* **Flexible Deployment:** Supports on-premise, cloud, and hybrid deployments.

#### Cons
* **Complex Setup:** This can be complex to set up and configure, requiring some technical expertise.
* **Less Developer-Friendly:** The interface and documentation may not be as user-friendly for developers.

#### Ideal Use Cases for Gluu Server
* Organizations requiring a complete IAM solution with a strong focus on standards compliance.
* Environments with a mix of protocols and technologies.

### 7. [FreeIPA](https://www.freeipa.org/page/Main_Page)

FreeIPA is an open-source solution that focuses on providing centralized identity management, authentication, and authorization services for Linux-based systems. It's primarily used for managing user accounts, groups, and system security policies.

#### Key Features of FreeIPA
* **Centralized User Management:** It provides a single point of control for managing user accounts, groups, and permissions on Linux systems.
* **Authentication and Authorization Services:** It handles user authentication and authorization for various Linux services and applications.
* **Kerberos and LDAP Integration:** It supports integration with Kerberos and LDAP for authentication and directory services.
* **System Security Policy Management:** It allows for configuring and enforcing security policies for Linux systems.
* **Automated Tasks:** Provides tools for automating user account management and system administration tasks.

#### Pros
* **Strong Linux Integration:** Deeply integrated with Linux systems and provides comprehensive management capabilities.
* **Secure and Reliable:** Uses strong security practices and is widely used in enterprise environments.
* **Automated Tasks:** Offers features for automating user account management and system configuration tasks.

#### Cons
* **Primarily Linux-Focused:** Not as suitable for managing identities in non-Linux environments.
* **Steeper Learning Curve:** Requires familiarity with Linux systems and command-line interfaces.

#### Ideal Use Cases for FreeIPA
* Linux-based environments that require centralized identity management and authentication.
* Organizations needing to manage user accounts, groups, and security policies on Linux systems.

## A Comparison Between Keycloak Vs Other Open Source Alternatives
Here we will be analyzing Keycloak side by side with each Open Source alternative.

### Keycloak Vs Zitadel
|Feature | Keycloak | Zitadel |
| -------- | -------- | -------- |
| Core Features | SSO, MFA, User Management, Fine-Grained Authorization | SSO, MFA, User Management, Microservices-Oriented |
| Supported Protocols | OpenID Connect, OAuth 2.0, SAML | OpenID Connect, OAuth 2.0, SAML |
| Deployment Options | On-Premise, Cloud, Hybrid | Cloud-Native (Docker/K8s), Cloud |
| Community and Support | Large, Active | Growing |
| Scalability and Performance | Good | Excellent |
| Ease of Use | Good | Moderate |
| Complexity | Moderate | Moderate |

### Keycloak Vs Apereo CAS
|Feature | Keycloak | Apereo CAS |
| -------- | -------- | -------- |
| Core Features | SSO, MFA, User Management, Fine-Grained Authorization | SSO, MFA, User Provisioning, Multi-Protocol Support |
| Supported Protocols | OpenID Connect, OAuth 2.0, SAML | OpenID Connect, OAuth 2.0, SAML |
| Deployment Options | On-Premise, Cloud, Hybrid | On-Premise, Cloud |
| Community and Support | Large, Active | Large, Established |
| Scalability and Performance | Good | Good |
| Ease of Use | Good | Moderate |
| Complexity | Moderate | High |

### Keycloak Vs Apache Syncope
|Feature | Keycloak | Apache Syncope |
| -------- | -------- | -------- |
| Core Features | SSO, MFA, User Management, Fine-Grained Authorization | User Provisioning, Governance, Access Management |
| Supported Protocols | OpenID Connect, OAuth 2.0, SAML | OpenID Connect, OAuth 2.0, SAML |
| Deployment Options | On-Premise, Cloud, Hybrid | On-Premise, Cloud |
| Community and Support | Large, Active | Moderate, Active |
| Scalability and Performance | Good | Good |
| Ease of Use | Good | Moderate |
| Complexity | Moderate | High |

### Keycloak Vs LemonLDAP::NG
|Feature | Keycloak | LemonLDAP::NG |
| -------- | -------- | -------- |
| Core Features | SSO, MFA, User Management, Fine-Grained Authorization | SSO, Multi-Protocol Support, High Customization |
| Supported Protocols | OpenID Connect, OAuth 2.0, SAML | OpenID Connect, OAuth 2.0, SAML |
| Deployment Options | On-Premise, Cloud, Hybrid | On-Premise, Cloud |
| Community and Support | Large, Active | Moderate, Active |
| Scalability and Performance | Good | Good |
| Ease of Use | Good | Moderate |
| Complexity | Moderate | Moderate |

### Keycloak Vs WSO2 Identity Server
|Feature | Keycloak | WSO2 Identity Server |
| -------- | -------- | -------- |
| Core Features | SSO, MFA, User Management, Fine-Grained Authorization | Comprehensive IAM, Scalable Architecture, Advanced Features |
| Supported Protocols | OpenID Connect, OAuth 2.0, SAML | OpenID Connect, OAuth 2.0, SAML, Others |
| Deployment Options | On-Premise, Cloud, Hybrid | On-Premise, Cloud |
| Community and Support | Large, Active | Large, Enterprise-Focused |
| Scalability and Performance | Good | Excellent |
| Ease of Use | Good | Moderate |
| Complexity | Moderate | High |

### Keycloak Vs Gluu Server
|Feature | Keycloak | Gluu Server |
| -------- | -------- | -------- |
| Core Features | SSO, MFA, User Management, Fine-Grained Authorization | SSO, MFA, Centralized Management |
| Supported Protocols | OpenID Connect, OAuth 2.0, SAML | OAuth2.0, OpenID Connect, SAML, SCIM |
| Deployment Options | On-Premise, Cloud, Hybrid | On-premises, Cloud, Hybrid |
| Community and Support | Large, Active | Strong (Active community) |
| Scalability and Performance | Good | Good |
| Ease of Use | Good | High |
| Complexity | Moderate | Moderate |

### Keycloak Vs FreeIPA
|Feature | Keycloak | FreeIPA |
| -------- | -------- | -------- |
| Core Features | SSO, MFA, User Management, Fine-Grained Authorization | Centralized Identity Management, Linux-Focused |
| Supported Protocols | OpenID Connect, OAuth 2.0, SAML | Kerberos, LDAP, Others |
| Deployment Options | On-Premise, Cloud, Hybrid | On-Premise, Cloud |
| Community and Support | Large, Active |Active, Linux-Focused |
| Scalability and Performance | Good | Good |
| Ease of Use | Good | Moderate |
| Complexity | Moderate | High |

## Factors to consider When Choosing Keycloak Open Source Alternative
When selecting the right Keycloak alternative, several factors come into consideration but here are some factors to consider.

* **Project Size and Complexity:** If you have a small project and just need a basic way to log people in, a simple tool like LemonLDAP::NG might be all you need. But if you're a big company with lots of different users and complicated security needs, you might want to use a more powerful tool like WSO2 Identity Server or Gluu Server.

* **Required Features and Functionalities:** If you need tracking how users are using your website or setting very specific rules about what they can do, WSO2 Identity Server or Gluu Server can do those things. They have more advanced features than some of the simpler tools.

* **Deployment Preferences (Cloud vs. On-Premise):** Depending on how you want run your software either on your own servers (on-premise) or in the cloud. Zitadel is built for the cloud, while Keycloak and Apache Syncope give you both options.

* **Technical Expertise:** Based your technical team's skills and resources. Tools like Keycloak and Zitadel, are easier to learn and use. FreeIPA, on the other hand, requires someone who has some experience about Linux.

### Conclusion
We've looked at seven popular open-source tools that can help you manage user accounts and security. Each one has its own strengths and weaknesses, so the best choice for you depends on what you need for your project.

We encourage you to explore the links provided and delve deeper into the world of open-source IAM solutions. You might also consider checking out [Permify](https://permify.co), a modern, cloud-native solution focused on policy-based access control and fine-grained authorization, which offers an interesting alternative for building secure and flexible access management systems.

### Additional Resources
Links to Official Websites, Documentation, and Community Forums:

* [Keycloak Documentation](https://www.keycloak.org/docs/)
* [Keycloak Community Forum](https://groups.google.com/forum/#!forum/keycloak-user)
* [Zitadel Community Forum](https://github.com/zitadel/zitadel/discussions)
* [Apereo CAS Documentation](https://www.javadoc.io/doc/org.apereo.cas)
* [Apereo CAS Community Forum](https://apereo.slack.com/)
* [Apache Syncope Documentation](https://syncope.apache.org/docs/)
* [LemonLDAP::NG Documentation](https://lemonldap-ng.org/documentation/latest/)
* [WSO2 Identity Server Documentation](https://wso2.com/documentation/)
* [WSO2 Identity Server Community Forum:](https://wso2.com/forum/)
* [Gluu Server Documentation](https://gluu.org/docs/)
* [FreeIPA Documentation](https://www.freeipa.org/page/Documentation)