Contact-Proximity-Interface: Proximity Communication Interface
| Source Element | Destination Element | Flow |
|---|---|---|
| COTA SMART Card | COTA Ticket Vending Machines | payment |
| COTA Transit Fixed–Route Vehicles | payment | |
| COTA Ticket Vending Machines | COTA SMART Card | request for payment |
| COTA Transit Fixed–Route Vehicles | COTA SMART Card | request for payment |