A system for transmitting data via a power line including: a first communications device and a second communications device, the first communications device including a transmit unit adapted to generate OFDM symbols to be transmitted using sub-carriers; a roll-off interval indication unit adapted to generate a transmit message indicating that no roll-off interval before and/or after the OFDM symbols is used when transmitting the data; the transmit unit being further adapted to transmit the transmit message; the second communications device including a receive unit adapted to generate the data from the transmitted OFDM symbols by taking into account the received transmit message.