A technique is provided for echo cancellation. The technique includes marking respective source signals with a respective marker signal to identify respective starting time references of the respective source signals and to identify respective transmitters to transmit respectively obtained marked source signals, transmitting the respectively marked source signals by the respective transmitters to at least one aggregate node, summing the respective marked source signals received by the at least one aggregate node to create a multicast signal for provision, via a multicast node, to respective receivers associated to the respective transmitters, determining respective round trip power normalization and round trip delay values for modifying, in the respective receivers, the respective marked source signals, to obtain respective delayed and normalized respective marked source signals, and subtracting, at the respective receivers, the respective round trip delayed and normalized marked source signal from the multicast signal to obtain respective echo cancelled multicast signals in the respective receivers.