JWT

JWT (JSON Web Token) is commonly used in .NET to implement stateless authentication. Instead of storing a user's session on the server, the server issues a signed token after the user successfully logs in.

Here's the typical flow:

The user submits their username and password to the login endpoint.
The server validates the credentials against the database.
If the credentials are valid, .NET generates a JWT containing claims such as the user's ID, username, role, and an expiration time.
The token is returned to the client.
For every protected API request, the client sends the token in the Authorization header using the Bearer scheme.
The JWT middleware in ASP.NET Core validates the token's signature, issuer, audience, and expiration. If the token is valid, the request is allowed to access secured endpoints; otherwise, a 401 Unauthorized response is returned.

One of the biggest advantages of JWT is that the server doesn't need to store session information. Everything required to identify the user is contained in the token itself, making it ideal for REST APIs and microservices.

A JWT consists of three parts:

Header – Specifies the token type and signing algorithm.
Payload – Contains claims such as user information and roles.
Signature – Ensures the token hasn't been modified after it was issued.

In ASP.NET Core, JWT authentication is typically configured using AddAuthentication(), AddJwtBearer(), and the [Authorize] attribute to protect API endpoints.

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Cynthia Sathuragiri1mo ago
JWT (JSON Web Token) is commonly used in .NET to implement stateless authentication. Instead of storing a user's session on the server, the server issues a signed token after the user successfully logs in.
Here's the typical flow:
1. The user submits their username and password to the login endpoint.
2. The server validates the credentials against the database.
3. If the credentials are valid, .NET generates a JWT containing claims such as the user's ID, username, role, and an expiration time.
4. The token is returned to the client.
5. For every protected API request, the client sends the token in the Authorization header using the Bearer scheme.
6. The JWT middleware in ASP.NET Core validates the token's signature, issuer, audience, and expiration. If the token is valid, the request is allowed to access secured endpoints; otherwise, a 401 Unauthorized response is returned.
One of the biggest advantages of JWT is that the server doesn't need to store session information. Everything required to identify the user is contained in the token itself, making it ideal for REST APIs and microservices.
A JWT consists of three parts:
- Header – Specifies the token type and signing algorithm.
- Payload – Contains claims such as user information and roles.
- Signature – Ensures the token hasn't been modified after it was issued.
In ASP.NET Core, JWT authentication is typically configured using AddAuthentication(), AddJwtBearer(), and the [Authorize] attribute to protect API endpoints.