Abstract: A data communication method is described for transmitting a data packet comprising data bytes in a daisy chained bus structure of a LED illumination system. The method comprises: the nodes of a group, except the last node of the group retransmitting the data packet without removing a first data byte from the incoming data packet; and the last node in the group removing the first byte from the data packet before retransmission. The invention further comprises a communication node, illumination assembly and bus structure implementing the method according to the invention.