A symmetric key management process in a communication network comprising a source device furnished with a source of data to be broadcast over the network and at least one receiver device intended to receive the broadcast data. The process comprises: determining and securely transmitting a first symmetric key to a receiver device; the receiver device encrypting the first symmetric key using a second symmetric key and transmitting it to the source device; and the source device recovering and storing it. Before transmitting the data to at least one reception device, the source device encrypts these data with the aid of the first symmetric key, then it transmits these encrypted data, accompanied by the first encrypted symmetric key, to at least one receiver device. The receiver device decrypts the first symmetric key with the aid of the second key which it possesses, then it decrypts the encrypted data with the aid of the first symmetric key thus recovered.