Portable smart card with personalisation and lottery function to encourage return

摘要

The smart card has a first memory zone (1) for storing personalisation information on the holder along with credits which are irreversibly counted down with use. A second memory zone (2) can be erased and written to. The value is this memory zone is modified after each used of the card. The value held after the last unit of credit has been used forms the key for a DES decryption function which is applied to encrypted information entered into a third zone of memory (3) when the personalisation information is entered. If the key results in correct decryption of the information in the third memory zone the card holder receives a prize.