This object, carried only inside storm-control trap notifications, indicates which traffic type, such as broadcast, multicast, or unknown unicast, triggered the storm event being reported. Admins use it in trap and NMS correlation to determine at a glance what kind of traffic caused a dStormCtrlOccurred or dStormCtrlStormCleared notification without cross-referencing the interface table. A trap carrying this object set to broadcast tells the admin the storm was caused by excessive broadcast traffic on the reporting port.