Authentication Concepts

JSON Web Tokens (JWT)

JWTs are compact, URL-safe tokens used in authentication, particularly in token-based authentication systems. They can carry a set of claims that are typically used to pass the identity of authenticated users between an identity provider and a service provider. JWTs can be signed using a secret key (using the HMAC algorithm) or a public/private key pair using RSA or ECDSA.

JSON Web Key Set (JWKS)

JWKS is a set of keys containing the cryptographic keys used for signing or encrypting the JWTs. Each key in the JWKS is represented as a JSON Web Key (JWK).

JWKS URI

The JWKS URI is a URL that points to a set of public keys used to verify the signatures of JWTs. The authentication server provides this URI and allows client applications to retrieve the public keys dynamically. This is particularly useful in scenarios where keys need to be rotated or updated without requiring manual updates in the client applications.

Use Case of JWKS in Authentication

When a JWT is used in an authentication process:

  • The JWT is generated and signed by an authentication server using a private key.

  • The JWT is sent to a client application, which then needs to verify the signature to trust the claims within the token.

  • The client application retrieves the public key from the JWKS URI provided by the authentication server. This key can verify the JWT's signature, confirming that the expected authentication server indeed issued the token and has not been tampered with.

  • The use of JWKS helps manage public keys efficiently and securely, especially in distributed systems or cloud-based environments where multiple services must verify tokens independently. It reduces the risk associated with key distribution and management, allowing for more scalable and secure authentication architectures.

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