A method of estimating a level of severity of a network fault is provided. Performance parameters are monitored on upstream and downstream links to terminal network elements on a network to detect potential network faults. An alarm is raised with respect to a potential network fault automatically if at least one of the performance parameters as monitored crosses a preset threshold. After an alarm is raised, a level of severity is assigned to the alarm based on pre and post forward error correction (FEC) bit error rates (BER). In addition, the total number of terminal network elements that are impacted by the network fault is estimated and, when multiple alarms are raised of an equal level of severity, a higher priority is placed upon an alarm that affects service to a greatest number of terminal network elements.