Patent ID: 8073426

Claim:
An authentication vector generation device comprising: authentication vector generating means for generating an authentication vector used to authenticate a subscriber identity module in a wireless local area network connected to a mobile communication network, said authentication vector having a random number field for storing random numbers used in an authentication calculation performed in said subscriber identity module; attaching means for attaching, inside said random number field of said generated authentication vector, a calculation information element including information, separate from the random numbers stored in the random number field, specifying an algorithm and secret information having a predetermined number of bits for use in said authentication calculation, the number of bits of the secret information being set differently for each of a plurality of algorithms specified by the calculation information element; and transmitting means for transmitting to said mobile communication network said random number field which includes said calculation information element, wherein said subscriber identity module initiates said authentication calculation based on said calculation information element including information separate from the random numbers specifying said algorithm and secret information.