User connects WiFi
       ↓
OpenNDS
       ↓
Client redirected to voucher login page (PHP)
       ↓
Voucher submitted → check database
       ↓
If valid → router firewall allows client IP
       ↓
Apply speed limit (1 Mbps)
       ↓
Monitor session → stop if:
         - time > 1h
         - data > 5GB
         -Speed > 1mbps