A method of transmitting data from a sender to a number of recipients in a system with a multilayer protocol architecture, in which the data are divided for organizational purposes into data packets having header data and payload data, a transmitting and/or receiving unit and a communication system. The transmission of data in the form of a point-to-multipoint transmission over a general channel, in particular in a mobile radio system, is carried out by adding to packet data which are being sent to multicast groups control data for the identification of a specific multicast group.