Abstract: A computer-implemented method of generating keys of a hierarchical key structure, wherein the method is performed by a key generator and comprises: obtaining a child key derivation path, wherein the child key derivation path comprises a sequence of elements, wherein the sequence of elements comprises one or more sets of one or more elements, each set of elements being generated based on a respective data item of a data path, and wherein each element in the sequence corresponds to a respective position of key in a respective level of the key structure; and generating one or more child keys based on the child key derivation path, wherein each respective child key is generated based on a respective element in the sequence at the respective position and of the respective level corresponding to that respective element.

Abstract: A gaming system for placing bet and/or lottery wager orders includes at least one portable player identification device (12), each player identification device (12) storing a respective digital invariant unique identification code in a memory (14) and including a short range wireless communication interface (16) enabling to read the identification code in the memory; and at least one interface (8, 10) having a short range wireless communication reader (24, 30) for reading the identification code stored in a player identification presented to the reader (24, 30), the interface being configured to confirm execution of a pending bet and/or lottery wager order to a gaming platform (3), each pending order being associated to an identification code, with requesting presentation of the player identification device (12) matching the identification code associated to the pending order to allow confirmation of the pending order.