The tmnxDot3OamSdThresholdEvent notification is generated when a local or remote threshold crossing event for signal degradation is detected. A local SD threshold crossing event is detected by the local entity, while a remote threshold crossing event is detected by the reception of an Ethernet OAM Event Notification OAMPDU that indicates an SD threshold event. This notification will not be sent more than once per second. The OAM entity can be derived from extracting the ifIndex from the variable bindings. The objects in the notification correspond to the values in a row instance in the tmnxDot3OamSdEventLogTable. The management entity should periodically check tmnxDot3OamSdEventLogTable to detect any missed events.