An automated method of characterizing distortion detected by equalization on a channel of a network is provided. Equalization stress of an observed channel equalization response of an end device of the network is estimated, and equalization stress is calculated for a theoretical channel equalization response of the end device mathematically based on the observed channel equalization response and a theoretical removal of a suspected impairment from the network. The above referenced calculating step is separately repeated for each of a plurality of suspected impairments stored in a database of suspected impairments. A highest ranking suspected dominant impairment is determined from the database of suspected impairments such that removal of the highest ranking suspected dominant impairment from the network would provide a greatest reduction of equalization stress of a channel equalization response of the end device.