'Sign-on' once to access one or more resouces:
| Person: | Network: | | |
| Provide credentials. | | | |
| | Enter: | | | |
| | - User_Prinicipal_Name | | | |
| | - Password-------------- | ------> | | |
| | Analize credentials. | | |
| | | Verify as authentic. | | |
| | Authorize person to access network. | | |
| | Provide access to one or more resources. | | |
| | | | | |
| | | | |
A set of credentials can authorize a person to use the entire network.