Token-based authentication is a popular method used to manage user access to applications. It provides a stateless, scalable, and efficient way to authenticate users. In this tutorial, we will explore the basics of token-based authentication and how it works.

Overview

  • What is Token Based Authentication? Token-based authentication is a mechanism where a token is used to verify the identity of a user. This token is typically a string of characters that is issued to the user after they have successfully logged in.

  • Why Use Token Based Authentication?

    • Stateless: Tokens are stateless, which means that they do not require a server to maintain a session.
    • Scalable: It is easy to scale because there is no need to maintain a session on the server.
    • Secure: Tokens can be encrypted and signed to ensure that they are not tampered with.

How Token Based Authentication Works

  1. User Logs In

    • The user provides their credentials (username and password) to the server.
    • The server verifies the credentials and generates a token.

  2. Token Issued

    • The server sends the token to the user, typically in the form of a JSON Web Token (JWT).
    • The token contains information about the user, such as their ID and permissions.

  3. User Accesses Resource

    • The user sends the token with each request to the server.
    • The server validates the token and grants access to the resource.

Example

Suppose you are building a web application that requires authentication. When a user logs in, the server generates a JWT and sends it back to the user.

{
  "token": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyfQ.SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c"
}

The user includes this token in the Authorization header of each request to the server.

GET /api/resource HTTP/1.1
Host: example.com
Authorization: Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyfQ.SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c

The server validates the token and grants access to the resource.

Learn More

For more information on token-based authentication, you can read our detailed guide on Understanding Token Based Authentication.

Understanding Token Based Authentication