The form-based authentication scheme works in the following manner:

* A client generates a request for a protected resource (e.g. a transaction details page).
* The Internet Information Server (IIS) receives the request. If the requesting client is authenticated by IIS, the user/client is passed on to the Web application.
* If the client does not contain a valid authentication ticket/cookie, the Web application will redirect the user to the URL where the client is prompted to enter his credentials to gain access to the secure resource.
* On providing the required credentials, the client is authenticated/processed by the Web application.