An hpEntConfigChange trap is sent when the value of hpEntLastChangeTime changes. It can be utilized by an NMS to trigger logical/physical entity table maintenance polls. An agent must not generate more than one hpEntConfigChange 'trap-event' in a five second period, where a 'trap-event' is the transmission of a single trap PDU to a list of trap destinations. If additional configuration changes occur within the five second 'throttling' period, then these trap-events should be suppressed by the agent. An NMS should periodically check the value of hpEntLastChangeTime to detect any missed hpEntConfigChange trap-events, e.g. due to throttling or transmission loss.