1. Using mikrotik v5.26 RB450 as captive web portal
2. Do a guest login web page with following step:
2.1 Guest use its Facebook account to login
2.2 New visitor needs to join a given fans group or page with "like"
2.3 Guest "check-in" a given location
2.4 Then the guest can browse the internet
3. A linux server could be prepared if needed.
4. Mikrotik provides DHCP service for wifi station.
5. WiFi AP using a fixed IP.
WiFi NB -----WiFi AP ----RB-450 -----Internet