AWS IAM supports identity federation by allowing external identity providers that use OpenID Connect (OIDC) to authenticate and assume IAM roles. According to the AWS Certified Security – Specialty documentation, IAM OIDC identity providers are the recommended approach for enabling third-party systems, such as external CI/CD pipelines or Git-based repositories, to securely obtain temporary AWS credentials without using long-term access keys.

By creating an OIDC identity provider in IAM and configuring the IAM role trust policy to trust the external IdP, the company enables secure, token-based authentication. The trust policy can include conditions that restrict which repositories, branches, or workflows are allowed to assume the role, enforcing least privilege. AWS Security Specialty guidance emphasizes that this method eliminates static credentials and relies on short-lived tokens issued by the OIDC provider.

Option B is incorrect because IAM Roles Anywhere is designed for workloads running outside AWS that use X.509 certificates, not OIDC. Option C is intended for workforce identity federation, not machine-to-machine authentication. Option D is invalid because AWS RAM does not provide identity federation or authentication capabilities.

This solution aligns with AWS best practices for secure, scalable, and low-overhead authentication for external workloads.

Referenced AWS Specialty Documents:

AWS Certified Security – Specialty Official Study Guide

AWS IAM OIDC Identity Providers

AWS IAM Role Trust Policies