A method for distributing identifiers of sources from a multicast group. The sources are interconnected via an electronic communications network, and the multicast group is identified by a group address. A stream transmitted to the group address by a first source is received by a second source if the second source is already subscribed to the first source. One of the sources, known as the server, is subscribed to all of the other sources. The method includes the server performing the following acts: receiving from one of the other sources, known as an announcer source, a multicast announcement message including an announcer source identifier; and transmitting a management message to the group address, including the announcer source identifier.