A method and a device are disclosed for concentration of messages transmitted by at least two separate transmitters in a communication network to which there are connected these transmitters and an addressee of the data contained in the messages. After receiving the messages to be concentrated, the data contained in these messages are extracted. A concentration frame comprising the extracted data and at least one information item making it possible to identify the addressee is then constructed and transmitted The size of the concentration message is smaller than the maximum size of the data packets exchanged in the communication network.