I'm looking at allowing internet access for only a few scattered users on a school network. One method I'm considering is using 802.1x authentication for the modem. Of course there are simpler options like only allowing specific IP or mac addresses, but policy requires something more secure than this.
So, are there any modems with 802.1x wired authentication? All my searching on this yields info about wireless.
I've never seen a modem that can be an 802.1x supplicant, and such a setup wouldn't restrict access to just a few users.
You could certainly put the modem onto a different VLAN and require 802.1x on the client machine to do dynamic VLAN allocation onto that network, but it seems like an overly-complicated way to go about it. (Further, you wouldn't be able to access resources on the 'normal' network ever)
If you really want to limit internet access to selected users, set up a VPN server to which they can connect, and then have only the VPN server have a route/connection to the modem.