Method for configuring a node device in a communication network in the form of a tree of node devices, implemented on an electrical power supply network, some node devices possibly being relays (130; 131; 133; 135) between a root node device of the tree and other node devices (134; 136; 137; 138; 139) that are respectively attached thereto, each transmission in the communication network in the direction of the root node device being an uplink transmission and each transmission in the opposite direction being a downlink transmission, characterized in that at least one node device performs the following steps: - obtaining (303, 304), from a parent node device to which said node device is attached, items of information in respect of quality of reception and of level of reception in relation to signals, said signals having been sent by said node device and received by said parent node device, the item of information in respect of quality of reception being an item of information in respect of signal-to-noise ratio; - using, to transmit signals in the framework of the downlink transmissions, a send level fixed at a maximum send level of said node device; and - determining (306, 308) a send level V of said node device that is used to transmit signals in the framework of the uplink transmissions, so as to continue to enable said parent node device to receive said signals, while minimizing interference linked with crosstalk phenomena, said send level V being determined by implementing the following steps: - determining a first difference between said item of information in respect of signal-to-noise ratio and a predefined minimum signal-to-noise ratio (SNR_OK); - determining a second difference between said item of information in respect of level of reception (RX_LV) and a predefined minimum level of reception (RX_LV_OK); - determining a minimum difference between the first and the second difference; - calculating the send level V by subtracting said minimum difference from a send level (N_Tx_U) used by said node device to send the signals to which the item of information in respect of quality of reception and the item of information in respect of level of reception relate; - replacing the send level V with the maximum send level (N_Tx_Max) if V is greater than the maximum send level, and with a predefined minimum send level (N_Tx_Min) if V is lower than the predefined minimum send level. - obtaining (303, 304), from a parent node device to which said node device is attached, items of information in respect of quality of reception and of level of reception in relation to signals, said signals having been sent by said node device and received by said parent node device, the item of information in respect of quality of reception being an item of information in respect of signal-to-noise ratio; - using, to transmit signals in the framework of the downlink transmissions, a send level fixed at a maximum send level of said node device; and - determining (306, 308) a send level V of said node device that is used to transmit signals in the framework of the uplink transmissions, so as to continue to enable said parent node device to receive said signals, while minimizing interference linked with crosstalk phenomena, said send level V being determined by implementing the following steps: - determining a first difference between said item of information in respect of signal-to-noise ratio and a predefined minimum signal-to-noise ratio (SNR_OK); - determining a second difference between said item of information in respect of level of reception (RX_LV) and a predefined minimum level of reception (RX_LV_OK); - determining a minimum difference between the first and the second difference; - calculating the send level V by subtracting said minimum difference from a send level (N_Tx_U) used by said node device to send the signals to which the item of information in respect of quality of reception and the item of information in respect of level of reception relate; - replacing the send level V with the maximum send level (N_Tx_Max) if V is greater than the maximum send level, and with a predefined minimum send level (N_Tx_Min) if V is lower than the predefined minimum send level. - determining a first difference between said item of information in respect of signal-to-noise ratio and a predefined minimum signal-to-noise ratio (SNR_OK); - determining a second difference between said item of information in respect of level of reception (RX_LV) and a predefined minimum level of reception (RX_LV_OK); - determining a minimum difference between the first and the second difference; - calculating the send level V by subtracting said minimum difference from a send level (N_Tx_U) used by said node device to send the signals to which the item of information in respect of quality of reception and the item of information in respect of level of reception relate; - replacing the send level V with the maximum send level (N_Tx_Max) if V is greater than the maximum send level, and with a predefined minimum send level (N_Tx_Min) if V is lower than the predefined minimum send level.