Patent ID: 8681991

Claim:
An identification system comprising: at least one user medium; wherein the medium is equipped to store a derived key and to use the derived key to authenticate itself to a read and/or write device, the identification system further comprising a first key dispenser medium which contains a monolithic first integrated circuit with memory means and processor means, wherein the first integrated circuit is equipped to decrypt and store an encrypted source key, wherein the first integrated circuit is equipped to derive the derived key from the source key and to forward said derived key for storage in the user medium, the identification system further comprising another key dispenser medium containing another monolithic first integrated circuit with memory means and processor means, wherein the first integrated circuit of the first key dispenser medium is equipped to encrypt the source key for forwarding to the other key dispenser medium, and wherein said other key dispenser medium is a reduced key dispenser medium which is capable of deriving the derived key from the source key and of forwarding it for storage in the user medium, and which is not capable of providing the source key in such an encrypted form that it can be decrypted and stored by yet another key dispenser medium or reduced key dispenser medium.