The ORCA card system in the Seattle area is a great architecture question. You have a bus/transportation system that has: 1. RFID cards that tie into 2. Elect

The ORCA card system in the Seattle area is a great architecture question. You have a bus/transportation system that has: 1. RFID cards that tie into 2. Electronic wallets 3. The busses are not always internet connected 4. You need to be able to refill your card either online, or via kiosk. 5. You also want to be able to refund card balances. What system can solve this? What drawbacks would the system have? How could the system be scammed? Bonus questions are: "6. The LINK rail allows you go scan your ORCA card when you get on and get off the train, so you only pay for the number of stops you're on. How would you include that? 7. ORCA cards also allow for free transfers-- so if you take a second ride within 3 hours, it will be free. How would you include that?"