Avionic system of an aircraft

The avionic system of an aircraft includes a set of avionic computers and a switch associated with each avionic computer. For each avionic computer of the set of avionic computers, the avionic system includes a communication link between the switch associated with this avionic computer and each of the switches associated with the other avionic computers. Each switch is configured such that it routes the data frames received on its input ports to its output ports in a manner predefined only on the basis of the input ports on which these data frames are received. The various switches are configured such that, when an avionic computer sends a data frame, this data frame is transmitted to all of the other avionic computers.