The Best OAuth2 Proxy Alternative: Pomerium

An OAuth2 proxy is a reverse proxy server that sits in front of a web application or service to protect access using OAuth2 or OpenID Connect (OIDC) authentication protocols. It acts as an intermediary between the users and the backend services, ensuring that only authenticated users can access protected resources. 

The OAuth2 proxy itself does not perform authentication but delegates the task to an external OAuth2-compliant identity provider (IDP) to verify the user’s identity.

Although the OAuth2 proxy is easy to deploy and free, it has some limitations. Before deploying an OAuth2 Proxy, check out Pomerium, one of the best alternatives that offers enhanced features and security.

Summary: OAuth2 Proxy Vs. Pomerium Reverse Proxy

Here is the key takeaway of why Pomerium is considered the best OAuth2 alternative. 

Reasons Pomerium is the Best OAuth2 Proxy Alternative

Pomerium is considered one of the best OAuth2 proxy alternatives for several key reasons. It stands out as a secure, flexible, and modern identity-aware proxy that addresses many of the limitations found in traditional OAuth2 proxies. Here are the core factors that make Pomerium a superior alternative:

1. Identity-Aware Proxy (IAP) Features

Unlike traditional OAuth2 proxies, which focus mainly on authenticating users using OAuth2 providers, Pomerium acts as a full identity-aware proxy. It not only handles authentication but also ensures that access is granted based on user identity, context, and policies. This makes it a more holistic security solution, moving beyond just user authentication to focus on access control.

2. Fine-Grained Authorization

Pomerium integrates seamlessly with various identity providers (like Okta, Azure AD, Google Identity) and supports fine-grained access policies. These policies can be created using flexible access control logic based on identity attributes (e.g., group membership, roles, or geolocation) and contextual factors (e.g., time of day, IP address).

• OAuth2 proxy: Typically allows or denies access based only on whether a user has authenticated via OAuth2.

• Pomerium: Allows for context-aware policies, offering a zero-trust security model that can enforce stricter control for sensitive services and environments.

3. Single Sign-On (SSO) Support

Pomerium has built-in support for Single Sign-On (SSO) with all major identity providers, simplifying the user experience by allowing users to authenticate once and gain access to multiple applications or services.

While OAuth2 proxies also offer SSO via OAuth providers, Pomerium supports more advanced SSO use cases like access to internal applications and those that may not traditionally integrate with OAuth2 easily.

4. Secure by Design

Pomerium is designed with security in mind. It automatically handles secure connections between users and backend applications by managing TLS termination, encryption of traffic, and secure session management. It also comes with built-in features like mutual TLS (mTLS) for additional security.

• OAuth2 proxy: Typically requires more configuration to achieve these secure setups, often relying on third-party tools.

• Pomerium: Provides native support for these secure features, simplifying the process for administrators.

5. Support for Zero Trust Architecture

Pomerium excels in environments that require a zero-trust model. It can protect internal services, APIs, or other applications by authenticating and authorizing requests, even for non-browser-based traffic like APIs and CLI tools. This feature is particularly useful for modern distributed systems where traditional perimeter-based security is insufficient.

In contrast, OAuth2 proxy implementations may not support non-HTTP-based services and APIs well and typically focus only on web-based apps.

6. Ease of Use and Configuration

Pomerium offers a user-friendly configuration interface. Policies are declarative and written in YAML, making them easy to define and manage. Additionally, Pomerium integrates smoothly with popular orchestration platforms like Kubernetes, allowing users to deploy it in modern environments without much hassle.

While OAuth2 proxies can also be configured, they often require more manual intervention, especially when integrating with a variety of applications and environments.

7. Proxying More Than Just Web Apps

Unlike most OAuth2 proxies, which are often focused on web applications, Pomerium can proxy various types of services, including API endpoints and even internal developer tools. This versatility ensures that not only web applications but a broad range of services can be protected behind a secure identity-aware proxy.

8. Use of Standard Protocols

Pomerium supports open standards such as OAuth2, OIDC, and mTLS, ensuring compatibility with most modern identity providers and infrastructure components. It works well with both legacy systems and cloud-native environments, making it a flexible solution for organizations at various stages of digital transformation.

9. Observability and Debugging

Pomerium includes features like structured logging and metrics collection that make monitoring and debugging much easier compared to many OAuth2 proxy solutions. These observability features are essential for identifying issues in production and ensuring that security policies are enforced correctly.

Cost Consideration

Both OAuth2 proxy and Pomerium are open-source and free. 

Pomerium’s advanced features, particularly in paid versions (such as enterprise support and additional integrations), come with added costs of $7/user/month. However, the operational efficiencies gained from easier configuration, stronger security, and zero-trust architecture usually outweigh these costs.

Drawbacks of OAuth2 Proxies

• Limited Policy Control: OAuth2 proxies generally do not provide context-based policies or access controls beyond simple OAuth2 authentication.

• Higher Latency with External Services: OAuth2 proxies often rely on third-party tools and external services for TLS termination and access policies, potentially introducing latency and complexity.

• Manual Configuration: More manual configuration is needed for security features like TLS and managing multiple identity providers.

Conclusion

Pomerium's ability to go beyond basic OAuth2 authentication, its focus on context-aware access policies, seamless integration with identity providers, support for zero-trust environments, and ease of deployment make it a top-tier OAuth2 proxy alternative. It’s ideal for organizations looking to implement modern security practices while maintaining flexibility in controlling access to various services and applications.