The tmnxNatInAddrPrefixBlksFree notification is sent when all port blocks allocated to one or more subscribers associated with a particular set of inside addresses are released by this system. The type of subscriber(s) is indicated by tmnxNatNotifySubscriberType. The set of inside IP addresses is associated with the virtual router instance indicated by tmnxNatNotifyInsideVRtrID and is of the type indicated by tmnxNatNotifyInsideAddrType. The set of inside IP addresses consists of the address prefix indicated with tmnxNatNotifyInsideAddr and tmnxNatNotifyInsideAddrPrefixLen unless these objects are empty and zero; if tmnxNatNotifyInsideAddr is empty and tmnxNatNotifyInsideAddrPrefixLen is zero, the set contains all IP addresses of the indicated type. The values of tmnxNatNotifyMdaChassisIndex, tmnxNatNotifyMdaCardSlotNum and tmnxNatNotifyMdaSlotNum identify the ISA MDA where the blocks were processed. All notifications of this type are sequentially numbered with the tmnxNatNotifyPlSeqNum. This type of notification is typically the consequence of one or more configuration changes; the nature of these changes is indicated in the tmnxNatNotifyDescription.