Interference reduction for upstream signals in communication networks

Particular embodiments identify customer premise equipment (CPE) in a subscriber's premises that may potentially cause interference with other devices. For example, the interference may occur within an interfering spectrum where an interfering CPE transmits upstream in a frequency band that is the downstream frequency band for other customer premise equipment, such as legacy CPEs. Once the CPE is identified, when the CPE sends a request to initialize the CPE on the network, a cable modem termination service (CMTS) may adjust the target power level for a transmitter transmitting upstream content within the interfering frequency spectrum. For example, for those CPEs that transmit upstream using upstream channels within an interfering spectrum, such as within 54-85 MHz, the power level for these CPE may be reduced. Other CPEs that are not transmitting upstream in this interfering spectrum may not have their power reduced.