RFID ReaderSecurely storing a small photo onto an identity card to prevent card cloning.

In areas without Internet, card cloning is a problem. NFC pass cards and similar can easily be cloned and distributed. In the absence of Internet, the small storage space of an NFC card is used to contain not only the persons details, but a low resolution photograph of the owner.

All the data is encrypted and compressed to fit on the 4k of storage on the card. The card reader presents the information (including the photograph).

The encryption uses a 256-bit message digest of the data and 3072-bit RSA keys with padding. All official estimates put this as secure (not crackable) until beyond 2038! The resulting solution works entirely offline. Stolen, cloned or lost cards now have no value. You can see the image on the card, but if you modify any part of it the card is immediately flagged as not genuine (the message digest will no longer match). A stolen card reader has no value since it only holds the public key. Only the card writer holds the private key.


  • Client: Private Entrepreneur
  • Service: Solution, Software, Hardware