A broadcast system for broadcasting data streams includes a hierarchical network of data distributors starting from one central distributor (110) through at least one layer of intermediate distributors (120, 130, 140) to a plurality of broadcast receivers (150). Data streams are broadcast through downstream channels (160) of the network to the plurality of broadcast receivers. At least one distributor hierarchically below the central distributor is operative to insert broadcast data in at least one up-stream channel (170) of the network towards the central distributor. The central distributor is arranged to re-distribute broadcast data received via at least one up-stream channel through at least one downstream channel of the network.