| 摘要 |
A method of generating a segment key KS mt from a given basic key K MT and a given modification key K' MT in a key space with M*T keys. The basic key K MT is split into two parts L MT , R MT onto which a one-way function is applied M-m and T-t times, respectively, and the results are combined again to form a target basic key. A one-way function is applied to the modification key K' MT a number of times that corresponds to a distance value z between the given basic key and the segment key; in one preferred embodiment z=(M-m)+(T-t). This result is XOR-ed with the target basic key to obtain the segment key KS mt . Also provided is a device. |
