Method of detecting signal degradation fault conditions within sonet and SDH signals

摘要

In a method of detecting signal degradation conditions in synchronous digital signals, the error monitors first detect the presence and/or absence of a particular bit error ratio by integrating received parity errors over time. Subsequently a monitor client reacts to notifications from bit error rate monitors that the state of the presence/absence of specific bit error ratios has changed to generate an alarm condition when appropriate. <IMAGE>