The invention relates to a distributed data memory unit comprising a plurality of memory units, each having memory means and an access controller, an authentication unit comprising memory means and a validation unit, an execution controller comprising an execution controller module and an access verification unit, the execution controller communicating with the memory units and the authentication unit. At least one unambiguous electronic cipher is stored in the memory means of the authentication unit, the access verification unit has an access controller module and a memory unit. A first unambiguous cipher, which corresponds to a stored cipher of the authentication unit is stored in the memory unit and an assignment table is stored in the memory means of the memory unit. The invention also relates to a method for operating a distributed data memory unit.