Ligipääsutoken

Ligipääsutoken, often translated as access token, is a credential used in authentication and authorization protocols. It represents the permission granted to a client application to access specific resources on behalf of a user or on its own behalf. Access tokens are typically issued by an authorization server after a user has successfully authenticated and authorized the client application. The token itself is usually a string of characters that can be either opaque or structured, such as a JSON Web Token (JWT). The authorization server is responsible for validating the token, ensuring it has not expired, and checking if it grants the necessary permissions for the requested action. Clients include the access token in requests to resource servers, which then verify the token's authenticity and scope. Commonly used in OAuth 2.0 and OpenID Connect, access tokens facilitate secure delegated access without sharing user credentials directly with every application. They play a crucial role in modern web and mobile application security.