ASP.NET has ways to Authenticate a user:
1) Forms Authentication
2) Windows Authentication
Windows Authentication provider is the default authentication provider for ASP.NET applications. When a user using this authentication logs in to an application, the credentials are matched with the Windows domain through IIS.
There are 4 types of Windows Authentication methods:
1) Anonymous Authentication - IIS allows any user
2) Basic Authentication - A windows username and password has to be sent across the network (in plain text format, hence not very secure).
3) Digest Authentication - Same as Basic Authentication, but the credentials are encrypted. Works only on IE 5 or above
4) Integrated Windows Authentication - Relies on Kerberos technology, with strong credential encryption
Forms Authentication - This authentication relies on code written by a developer, where credentials are matched against a database. Credentials are entered on web forms, and are matched with the database table that contains the user information.
hope it helps :)
