The number of status polling intervals over which the
error threshold is counted. For example, if within
'MonitoredEvents' number of events the station receives
'ErrorThreshold' number of errors, the interface is
marked as down.
'status polling interval' is specified by
usdFrDlcmiPollingInterval.
Pertains to DTE/NNI operation only. This parameter can
be reconfigured only when the Frame Relay interface
is acting as a DTE or NNI.