What are JWT tokens used for in a microservices architecture?

JWT (JSON Web Token) is used in distributed microservices architecture to securely transmit information about a user or service between components.

Main tasks of JWT:

• Authentication: after user login, they receive a JWT confirming their identity.
• Authorization: microservices verify the token to determine what actions are permitted.
• Security: the token is signed, preventing tampering.

Example of usage:

1. User logs in and receives a JWT.
2. Client sends JWT in the Authorization header with requests to microservices.
3. Each microservice verifies the token's signature and data to confirm access rights.

This approach avoids centralized session storage and simplifies system scaling.