Identity Tokens Explained: Best Practices for Better Access Control

Identity tokens, such as JSON Web Tokens (JWTs) and OpenID Connect tokens, play a crucial role in modern application security by facilitating authentication across different services without handling raw credentials directly. While these tokens offer significant benefits, including simplifying authentication and supporting single sign-on, they have limitations and should not be used as a one-stop solution for both authentication and authorization. They should primarily focus on representing identity and not on managing permissions, as overloading them with information can lead to performance and security issues. Best practices include decoupling authentication from authorization, keeping tokens lean by including only essential claims, and adhering to standard protocols like OpenID Connect and OAuth 2.0. Additionally, maintaining a balance in token lifespan and having a strategy for token revocation are essential for security. Properly implemented, identity tokens enhance authentication processes while maintaining system security and flexibility, especially as the use of machine identities increases.