In the context of half-duplex communications in a communication network composed of a plurality of sub-networks associated respectively with supernode devices, a supernode device receiving a floor request: transmits a floor pre-grant message; determines a timer duration according to a distribution law fτ(t) for time period between a floor release and the next floor control, and a network-latency distribution law fδ(d), so that the probability of subsequent dismissing of the floor control is below a predefined threshold; and broadcasts the data transmitted in the context of the floor control, when the timer has elapsed. When a floor request with higher priority is detected before the expiration of the timer, the supernode device does not broadcast the data and notifies that the floor control is finally refused.