# Service to Service mTLS with Machine & Workload Identity

Using Workload Identity certificates reduces the risk of credential exfiltration and provides engineers with a built-in authentication method for new services. Each certificate is tied to the identity of the application itself, rather than relying on a shared certificate infrastructure or API key that can be copied or reused. This ensures that authentication and authorization are both more secure and reliable.

## Eliminate secrets from your applications

Teleport issues special credentials to applications in the form of x.509 certificates or JWTs, after verifying their identity (to get started, see [Introduction to Workload Identity](https://goteleport.com/docs/machine-workload-identity/workload-identity/introduction.md). These credentials are automatically rotated every 20 minutes by default. They contain a URI that uniquely identifies the application. Applications using the credentials automatically gain mTLS, and can verify that a request or response not only comes from a trusted certificate, but from a specific trusted application. This makes it possible to guarantee separation of tenants, geographic areas, etc.

## Improve developer efficiency and experience

With Teleport Machine & Workload Identity powering application to application authentication, developers can use standardized open-source libraries in their services to request a credential, and not worry about setting up API keys or integrating with custom PKI. Teleport Workload Identity credentials follow the SPIFFE standard, making them interoperable with a wide ecosystem of libraries and SDKs.

### Further reading

- [Best Practices for Teleport Workload Identity](https://goteleport.com/docs/machine-workload-identity/workload-identity/best-practices.md): Learn how Teleport verifies applications and issues credentials
- [Introduction to SPIFFE:](https://goteleport.com/docs/machine-workload-identity/workload-identity/spiffe.md) Learn about the open-source standard for workload identities and federation