expiration questions

To handle JWT expiration, set an expiration time when issuing the token and verify it on each request. Use refresh tokens to obtain a new JWT without requiring the user to log in again. Store refresh tokens securely and use them to request a new JWT from the server when the original token expires. Implement token rotation to enhance security.

The 'exp' claim in a JWT stands for 'expiration time' and indicates the point in time after which the token is no longer valid. This claim is represented as a Unix timestamp, specifying when the token should expire. The 'exp' claim is used to enforce token expiration and ensure that tokens are only valid for a specific duration. Once the current time exceeds the 'exp' time, the token is considered expired, and further requests with that token should be rejected to maintain security and session control.

To prevent JWT token replay attacks, implement several security measures. First, use short-lived tokens with expiration claims to limit the time a token is valid. Additionally, consider using refresh tokens to issue new access tokens and invalidate old ones. Implementing nonce values or unique identifiers within the token or request can also help detect and prevent replay attempts. Lastly, ensure that tokens are transmitted over HTTPS to prevent interception and unauthorized reuse.