Abstract: Redundant alarm messages generated by a plurality of Network Elements (NEs) in a Synchronous Optical Network (SONET) or Synchronous Digital Hierarchy (SDH) subnetwork are suppressed by a filter incorporated within a Subnetwork Controller (SBNC). In an illustrative embodiment of the invention, the SBNC filter collects and logs all alarm messages reported by the subnetwork NEs during a correlation period. After the period is completed, the filter determines whether at least one alarm that was reported during the period directly indicates a failure within the subnetwork and, if so, suppresses all other alarms arriving during the period that indicate conditions symptomatic of this failure. The correlation period persists for no longer than a maximum specified time period, and only so long as alarm messages continue to be reported during the interval.

Abstract: A data processing system is provided for identifying risks associated with abnormal conditions of network elements in a communications network. A data collection and processing module collects alarm message signals from a communications network and processes the alarm messages to general abnormal condition signals. An interface module also receives external condition signals indicative of external conditions affecting network elements in the communications network. The system provides an electronic risk processing module that generates direct and indirect risk signals based upon the abnormal condition signals, the external condition signals, and stored reference data. A display means displays a network element risk signal which is the sum of said direct and indirect risk signals. The displayed risk signal aids in assessing risks associated with network elements experiencing abnormal conditions. The system also generates and displays a sub-network risk signal.