A method for detecting the presence of one or more fault/s comprising: receiving, via a management interface, a measured SNR and/or a measured data rate; comparing a modeled SNR with the measured SNR for a given link, wherein the modeled SNR is derived from measured HLOG, measured QLN, transmit PSD, DSL standard information, link parameters, and known modem behavior, and/or comparing a modeled data rate with the measured data rate for a given link, wherein the modeled data rate is derived from measured HLOG, measured QLN, transmit PSD, DSL standard information, link parameters, and known modem behavior, and/or comparing a modeled with measured other noises for a given link, wherein the apparent fault noise is additive noise apparently attributable to the one or more fault/s and apparent fault noise and determined from the measured SNR, measured HLOG, measured QLN, transmit PSD, DSL standard information, link parameters, and known modem behavior, wherein the other noises are the sum of measured QLN and IntrinsicNoise; and determining the presence of one of the one or more faults caused by one or more unfiltered devices, impulse noises, malfunctioning modems, any non-linearity on the line, any noise source that is not present when the SNR is measured, or any other factor that does not affect measured attenuation or measured noise, but does affect the SNR; wherein the presenee of the fault is determined when the difference between the modeled SNR and the measured SNR and/or the difference between the modeled data rate and the measured data rate and/or the difference between the apparent fault noise and the measured other noises exceed/s a threshold. receiving, via a management interface, a measured SNR and/or a measured data rate; comparing a modeled SNR with the measured SNR for a given link, wherein the modeled SNR is derived from measured HLOG, measured QLN, transmit PSD, DSL standard information, link parameters, and known modem behavior, and/or comparing a modeled data rate with the measured data rate for a given link, wherein the modeled data rate is derived from measured HLOG, measured QLN, transmit PSD, DSL standard information, link parameters, and known modem behavior, and/or comparing a modeled with measured other noises for a given link, wherein the apparent fault noise is additive noise apparently attributable to the one or more fault/s and apparent fault noise and determined from the measured SNR, measured HLOG, measured QLN, transmit PSD, DSL standard information, link parameters, and known modem behavior, wherein the other noises are the sum of measured QLN and IntrinsicNoise; and determining the presence of one of the one or more faults caused by one or more unfiltered devices, impulse noises, malfunctioning modems, any non-linearity on the line, any noise source that is not present when the SNR is measured, or any other factor that does not affect measured attenuation or measured noise, but does affect the SNR; wherein the presenee of the fault is determined when the difference between the modeled SNR and the measured SNR and/or the difference between the modeled data rate and the measured data rate and/or the difference between the apparent fault noise and the measured other noises exceed/s a threshold.