This object carries the type of OAM (Operations, Administration, and Maintenance) status change that occurred on an EPON LLID (Logical Link ID), and is included as a variable binding when the device sends the corresponding trap. A network operator reads this value from a received trap to understand what kind of OAM state transition just happened on a subscriber's optical link. For example, an EPON monitoring system logs an oAMStatusChange trap value indicating OAM discovery was lost on a given LLID, prompting a truck-roll investigation.