摘要 |
The present invention relates to a method for dispatching at least one predetermined secret key, in order to make the implementation of a provision of service secure, characterized in that it comprises transmitting a predetermined implementation key in encoded form from a security module (MSCl) having a predetermined rank to a security module (MSTl) or card (U) of a rank lower than the predetermined rank, this encoding comprises using an encoding algorithm and introducing the predetermined implementation key, as well as least one diversified key, this diversified key, necessary for the encoding, being obtained by a diversification algorithm by introducing both a basic key of this diversified key and diversification data originating from the module of lower rank, the predetermined encoded implementation key being decoded by the use, in a module of lower rank than the predetermined rank, of a decoding algorithm which is the inverse of the encoding algorithm. |