Method for a communication system comprising an electronic device and a plurality of gateways, the electronic device and each gateway being adapted for sending and receiving frames on a radio frequency band, each gateway being connected to the same central server, a first frame being sent by the electronic device to the central server, the frame comprising an identifier of the electronic device, each gateway receiving said frame and transmitting the received frame, in association with an identifier of the gateway, to the central server, a response delay being predefined for responding to the first frame, the method allowing selection by the central server of a gateway among the plurality of gateways for sending a second frame to the electronic device in response to the first frame.