A protocol data unit switching implements switching means used for the
selective interconnection of a transmitter port and at least one receiver
port selected from among at least two receiver ports by means of at least
one internal bus, each of the protocol data units being constituted by at
least one piece of elementary data. The switching implements a
synchronization mechanism defining time slots, known as connection
cycles, on at least one of said internal buses; a mechanism for the
allocation of at least one of said connection cycles to each of the
selected receiver ports; and a mechanism for the writing of at least one
piece of elementary data in the allocated connection cycle or cycles so
as to enable the broadcasting of elementary data to said selected
receiver ports.