RMON events and alarms work together to notify you when values in your network go out of a specified range. When values pass the specified ranges, the alarm is triggered and "fires." The event specifies how the activity is recorded.
An event specifies whether a trap, a log, or a trap and a log will be generated to view alarm activity. When RMON is globally enabled, two default events are generated:
The default events specify that when an alarm goes out of range, the "firing" of the alarm will be tracked in both a trap and a log. For example, when an alarm fires at the rising threshold, the rising event specifies that this information be sent to both a trap and a log. Likewise, when an alarm passes the falling threshold, the falling event specifies that this information be sent to a trap and a log.