OAuthprotokollia

OAuthprotokollia is a framework that allows a user to grant a third-party application limited access to their data on another service without sharing their credentials. This is often used for single sign-on (SSO) functionalities where users can log into a new service using an existing account from another provider like Google or Facebook. The protocol operates on an authorization delegation model, meaning the user delegates specific permissions to the application.

The core concept of OAuth revolves around access tokens. Instead of giving an application direct access to a user's username and password, the application requests an access token from the authorization server. If the user approves the request, the authorization server issues an access token to the application. This token acts as a key, allowing the application to access specific resources on behalf of the user, as defined by the granted permissions.

OAuth defines several roles: the Resource Owner (the user), the Client (the third-party application), the Resource Server (where the protected resources are stored), and the Authorization Server (which issues access tokens). The process typically involves the Client redirecting the Resource Owner to the Authorization Server, where the user authenticates and authorizes the Client. The Authorization Server then redirects the user back to the Client with an authorization grant, which the Client uses to obtain an access token from the Authorization Server.

There are different flows within OAuth, such as the authorization code grant, implicit grant, and resource owner password credentials grant, each suited for different application types and scenarios. OAuth 2.0 is the current widely adopted version of the protocol. It aims to be simpler and more widely applicable than its predecessor.