Authentication is the process of obtaining identification credentials such as name and password from a user and validating those credentials against some authority. If the credentials are valid, the entity that submitted the credentials is considered an authenticated identity. Once an identity has been authenticated, the authorization process determines whether that identity has access to a given resource.

ASP.NET implements authentication through authentication providers, the code modules that contain the code necessary to authenticate the requestor's credentials. The topics in this section describe the authentication providers built into ASP.NET.