After a new NAC network is set up, the network administrator should pay attention to the number of potential access users and authentication method but does not need to control user access, because the administrator needs to configure user names, passwords, and authorization information on the authentication server. After 802.1X or MAC address authentication is configured on the access device, only authenticated users can access the network, so the administrator cannot obtain information about the users who do not have user names and passwords on the authentication server.
The NAC open function allows the users who failed in authentication to access the network.