[CAUSE] The tmnxNatMapRuleChange notification is sent with the value 'true' for tmnxNatNotifyTruthValue when a mapping rule becomes operational. The same notification is sent with 'false' when a mapping rule ceases to be operational. The value of the vRtrID object indicates in what virtual router instance the system applied the rule. The value of the tmnxNatNotifyDateAndTime object indicates at what time the system performed the change. [EFFECT] The system applies a given mapping rule in the time interval between the time it sends the notification with 'true' and the time it sent the notification with 'false'. [RECOVERY] Not required.