1. A method comprising the computer-implemented steps of: receiving a provisioning of one or more router access control lists, and one or more associations of the access control lists to users of the network device; wherein each access control list specifies network addresses of one or more of the users, associated network addresses for network resources that are available to corresponding users and a value indicating whether the corresponding users can access the available network resources; providing to the network device, as part of authenticating a user login request, a name of a first access control list from among the one or more access control lists that is selected based on the associations; receiving a request from the network device to obtain the first access control list that is associated with a user of the network device, wherein the request includes the name; sending the first access control list to the network device in response to the request; and wherein sending the first access control list to the network device in response to the request comprises sending the first access control list to the network device in an acceptance packet; notifying the network device that a challenge-response dialogue is starting; receiving a response that continues the challenge-response dialogue.