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Explained Web Authorization Techniques - Session & JWT

Understand important web authorization techniques to enhance role-based authentication for any web application with popular techniques like Session & JSON Web Token (JWT)

Intermediate

Anuj Sharma

Last Updated Dec 16, 2025

Authorization is about validating the user's permission to access the resources, in case of failure HTTP code "403 Forbidden" is returned.

Authorization Techniques

There are 2 major techniques for authorization, here are the details

1. Session-based authorizations - using Session Id

Authorization flow

The client sends a username & password to the server. The server validates credentials against existing credentials stored in the DB
On successful authentication server generates a unique session ID (signed) and stores session_id on the server.
The server sends back session_id which will be set as part of a cookie in the browser.
```
HTTP OK 200 set-cookie
```
All subsequent HTTP calls include session_id and request as part of the COOKIE request header.
The server validates session_id as part of the cookie against the stored cookie if valid then authorize the user to process that HTTP request.

Major drawbacks

Hard to load balance - Since this is a stateful mechanism, it requires the server to store the session ID, but in the case of multiple servers, this session is invalidated if the request is routed to another server by an API gateway or load balancer.

💡Solution - The above problem can be solved using common caching like Redis where all the servers will store and access session_id from Redis cache.
Prone to CSRF attacks - Session-based authentications are prone to CSRF attacks. This can be prevented by using the X-CSRF-Token header.
Access cookie by client-side application - Cookies can be accessed by any client-side application that can use the Cookie details to create a new session programmatically.
💡Solution - Cookies can be secured using HTTP-Only, same-origin options along with a Set-Cookie header so that it can't be accessible through JavaScript code.

2. Token-based authorization (Stateless) - JWT token

Authorization flow

The client sends a username & password to the server. The server validates credentials against existing credentials stored in the DB.
On successful authentication server generates a unique JWT Token, which contains data(payload) related to the user and signs that token.
This Token is sent back to the user as part of a successful HTTP response with the Authentication HTTP header
```
HTTP 200 OK Authentication: Bearer [Token]
```
Users save this token in a cookie or local storage
The user sends this token along with API requests in subsequent requests as part of the Authentication header.
The server validates the JWT token by decoding information from the JWT token. If the token is valid then the server authenticates that token and processes the API request.

Major drawbacks

Secret must be shared between servers so that the server can extract the user details.
In case of invalid Tokens(forgot password), requires a list of invalid tokens which makes a more sort of stateful kind.
Token-based authentications are prone to XSS attacks.
The token is not opaque and contains payload information, and this can be extracted from the token.
No sensitive information can be mentioned as part of the payload.
The generation of a new signature is essential a frequent intervals to avoid Resource Forgery attacks

About the Author

Anuj Sharma

A seasoned Sr. Engineering Manager at GoDaddy (Ex-Dell) with over 12+ years of experience in the frontend technologies. A frontend tech enthusiast passionate building SaaS application to solve problem. Know more about me 🚀

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3 comments

Is same technique used for authentication ?

1 reply

There are authentication techniques which uses the same concepts - Basic Authentication - uses cookies in the session OIDC (OpenID Connect) "Sign In with Google" - use OAuth2.0 which uses JWT concept

Very helpful to understand web Authorization.

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Explained Web Authorization Techniques - Session & JWT

Authorization Techniques

1. Session-based authorizations - using Session Id

2. Token-based authorization (Stateless) - JWT token

About the Author

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Comments

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