Method and system for embedding a unique and different digital watermark in digital contents for each access without increasing the overhear or load at the contents server. Embodiments of a TA operate to subdivide, by a request manager of the TA, fragment requests provided by the UA each into a plurality of chunk requests for requesting chunks of the content and to provide, by the RM to a connection manager of the TA, chunk requests of the plurality of chunk requests for requesting chunks of the content. The second mold portion is movable relative to the first mold portion. The disclosure also relates to a method for monitoring power transistors in said type of electronic control circuit with respect to the expected remaining service life thereof.