The value of tmnxDot3OamSdEventLogType indicates the type of SD threshold crossing event. When the OUI is the IEEE 802.3 OUI of 0x0180C2, the following event types are defined: erroredSymbolEvent(1), erroredFramePeriodEvent(2), erroredFrameEvent(3), erroredFrameSecondsEvent(4) When the OUI is not 71874 (0x0180C2 in hex), then some other organization has defined the event space. If event subtyping is known to the implementation, it may be reflected here. Otherwise, this value should return all F's (2^32 - 1).