An apparatus comprising at least one processor, at least one interface to at least one other network element, and a memory for storing instructions to be executed by the processor, wherein the at least one processor comprises a communication portion configured to conduct with at least one communication network control element (10, 15) a communication by using a demodulation reference signal based communication mode for signals received from the at least one communication network control element (10, 15), wherein the processor is further configured to generate in the demodulation reference signal based communication mode at least one predefined scrambling sequence of a demodulation reference signal, wherein each of the at least one scrambling sequence is generated by using a set of calculation parameters being specific for the respective scrambling sequence, wherein the set of calculation parameters is configurable during the at least one communication on the basis of configuration information received from the at least one communication network control element, wherein the processor is further configured to select, for initializing each of the at least one scrambling sequence before receiving the configuration information from the at least one communication network control element (10, 15), at least one predetermined default value selectable from a set of values comprising at least two predetermined default values for the set of calculation parameters of each of the at least one scrambling sequence, wherein the processor is configured to select the at least one default value on the basis of one of a preset instruction for the demodulation reference signal communication mode, or on the basis of an information indicating which default value is to be selected, the information being received via a control signaling, wherein the set of values comprises at least one value selectable as the predetermined default value which is determined by using an identification element of a terminal device as a parameter of a preset algorithm. at least one processor, at least one interface to at least one other network element, and a memory for storing instructions to be executed by the processor, wherein the at least one processor comprises a communication portion configured to conduct with at least one communication network control element (10, 15) a communication by using a demodulation reference signal based communication mode for signals received from the at least one communication network control element (10, 15), wherein the processor is further configured to generate in the demodulation reference signal based communication mode at least one predefined scrambling sequence of a demodulation reference signal, wherein each of the at least one scrambling sequence is generated by using a set of calculation parameters being specific for the respective scrambling sequence, wherein the set of calculation parameters is configurable during the at least one communication on the basis of configuration information received from the at least one communication network control element, wherein the processor is further configured to select, for initializing each of the at least one scrambling sequence before receiving the configuration information from the at least one communication network control element (10, 15), at least one predetermined default value selectable from a set of values comprising at least two predetermined default values for the set of calculation parameters of each of the at least one scrambling sequence, wherein the processor is configured to select the at least one default value on the basis of one of a preset instruction for the demodulation reference signal communication mode, or on the basis of an information indicating which default value is to be selected, the information being received via a control signaling, wherein the set of values comprises at least one value selectable as the predetermined default value which is determined by using an identification element of a terminal device as a parameter of a preset algorithm.