Authenticated routing

[junicast]

Hi guys,

imagine there was a bigger network with like 50-100 users and they're all within the same collision domain.
I would like to give people the opportunity to use this network completely free but then only for communication within that collision domain / broadcast domain. People who participate in paying for the uplink may as well use it.
For that purpose I would like to give those  people the possibility to securely authenticate agains my router.

I keep thinking of VPN based solutions for that but the encryption is way to much overhead and CPU hungry you could imagine.
What comes to your heads for such a scenario?

[viragomann]

Captive Portal
https://doc.pfsense.org/index.php/Captive_Portal