This section describes how to configure bit-error-triggered IGP route switching.
After bit-error-triggered IGP route switching is configured, if bit errors are generated on an interface, the link quality level of the interface changes to Low, triggering an IGP (OSPF or IS-IS) to increase the cost of the interface's link. IGP routes then do not preferentially select the link with bit errors. You can set different values for the bit error alarm and alarm clear thresholds. For example, to prevent jitters, set the alarm clear threshold to be one order of magnitude lower than the bit error alarm threshold. Bit-error-triggered IGP route switching ensures that the link with a lower BER is used to transmit traffic, minimizing the impact of bit errors on services.