# Web-Tech

notes

Session and token authentication

3 March 2024

Session and token authentication methods are used by the server to verify the client request is authenticated or not.

Session Authentication

Session-based authentication is an example of stateful authentication, which involves storing user authentication data on the server. With this method, when a user logs into a website, the server creates a small file that stores user information such as a unique session ID, login time, expiration time, and other relevant data. This file is stored in the database or in-memory cache. This session ID is then sent back to the client and stored in the client’s browser as a cookie. For subsequent requests, this cookie is passed back to the server. This allows the server to verify the session ID and provide a response based on the current state.

This method is easy to use, as cookies are natively supported by browsers, so no additional JavaScript is needed. But when the application grows decoupling the frontend from the backend becomes essential. Session-based authentication can be limiting in this regard.

Token Authentication

Instead of relying on server-side sessions, token-based authentication uses tokens and it is an example of stateless authentication. When user log in, the server create a token (usually a JSON Web Token, or JWT) using a secret key and sent to the user. For subsequent requests, user will send this token along with request and server will verify if the token is valid or not.

This method gives more scalability and stateless for the apps, but the server does not authenticate the user, so linking a token to its user can be more difficult. Also in any chance an attacker got acess to the token, they will get access to the server.

References

LogRocket, Authfear, criipto.

notes

What is a computer port?

23 August 2022

What is a port?

A port is a virtual point where network connections starts and end. Ports are software based and managed by a computer’s operating system. Each port is associated with a specific process or service. Ports allow computers to easily differentiate between different kinds of traffic: emails go to a different port than webpages, for instance, even though both reach a computer over the same Internet connection.

What is a port number?

Ports are standardized across all network-connected devices, with each port assigned a number. Most ports are reserved for certain protocols — for example, all Hypertext Transfer Protocol (HTTP) messages go to port 80. While IP addresses enable messages to go to and from specific devices, port numbers allow targeting of specific services or applications within those devices.

References

Cloudflare

notes

Stateless and Stateful

5 January 2022

The state of an application (or anything else, really) is its condition or quality of being at a given moment in time—its state of being. Whether something is stateful or stateless depends on how long the state of interaction with it is being recorded and how that information needs to be stored.

Stateless

A stateless process or applicaton can be understood in isolation. There is no stored information or references to past transactions. Each transaction is made as if from scratch for the first time. Think of stateless transactions as a vending machine: a single request and a response.

Stateful

Stateful applications and processes, however, are those that can be returned to again and again, like online banking or email. They’re performed with the context of previous transactions and the current transaction may be affected by what happened during previous transactions. For these reasons, stateful apps use the same servers each time they process a request from a user.

References

Redhat blog