Abstract: Digital modem for data exchange between a data distribution unit (2) and at least one receiver (3, 4) which can be connected to the digital modem (1) with: a user-data forward signal path (17) for the transmission of user data from the television-data distribution unit (2) to the receiver (3, 4) over broadband user-data forward transmission channels, a backward signal path (42) for the transmission of television-receiver control data from the receiver (3, 4) to the data distribution unit (2) over narrowband backward transmission channels; and with a control-data forward signal path (27) for the transmission of narrowband control data or user data from the data distribution unit (2) to the receiver (3, 4) over narrowband forward transmission channels, it additionally being possible for broadband user data to be transmitted over the control-data forward signal path (27) from the data distribution unit (2) to the receiver (3, 4).