Patent ID: 8756421

Claim:
An authentication system, comprising: an authentication device having a random number generating section for generating one of a true random number or a pseudo-random number, and a control section for using at least one code generated by the random number generating section to encrypt another code generated by the random number generating section, said authentication device registering both of the generated codes to an authentication apparatus in an initial setting, and the authentication apparatus for registering codes the same as said both of codes generated by the authentication device, in advance, in the initial setting, and for decrypting an encrypted code transmitted from an authentication device side by using the registered code and identifying thus decrypted code to perform the authentication, wherein the authentication device generates a new code, which is different from a previously registered code, by the random number generating section during the authentication or after the end of the authentication, and encrypts the new code using the registered code, and the authentication apparatus uses the code as registered to decrypt the encrypted new code transmitted from the authentication device side during the authentication or after the end of the authentication, and registers thus decrypted new code, whereby said code(s) having been registered in the authentication device and the authentication apparatus respectively are updated, and wherein a distributed content is encrypted, by using a key generated by using said updated new code, and is distributed to a user.