BAE Systems PLC
IMPROVEMENTS IN AND RELATING TO REMOTE AUTHENTICATION DEVICES

Abstract:

A remote authentication device includes a memory. The memory includes a one time pad comprising a series of bits. The memory includes circuitry arranged to retrieve a plurality of the bits from the one time pad. The circuitry is arranged to form a key from the plurality of bits and to use the key in a hash to generate an authentication code. The retrieval of the bits, forming of the key, and generation of the authentication code are repeated a plurality of times using a different plurality of bits from the one time pad.