Our company uses mifare ultralight cards for payments. What we do now is store nothing on the cards - everything is stored in the servers. I want to find out how we can safely store data in the card without exposing risks to other people hacking the stored value in the card. Is this possible with ultralight? Can this only be done using desfire? What particular features protect against this?
I basically need an expert to explain to us how this can be done, to explain why, and to prove the theory through a proof of concept test (optional)
Please include the phrase "smartcards are easy" if you read this description.