Password protected device using incorrect passwords as seed values for pseudo-random number generator for outputting random data to thwart unauthorized accesses

摘要

An electronic key which includes a pseudo-random number generator. If the correct password is received, the contents of a secure memory will be outputted by the electronic key. However, if an incorrect password is received, that password will be used as a seed value for the pseudo- random number generator, and the resulting value will be outputted. PPThus, if a copier exercises the key through all possible passwords, the incorrect passwords, as well as the correct password, will result in the same output data every time it is tried.