This read-only Counter64, in packets, counts packets the Customer Edge device received on this MAP domain whose destination port number falls outside the range configured for that CE, discarding each one it flags. An admin monitors this to detect subscriber traffic being sent to ports outside their assigned PSID port-set, which could indicate a misconfigured application or an attempted port-range violation. For example, a growing InvV4Pkts count on a domain suggests a device behind that subscriber's mapped address is trying to use ports outside its allotted port-set.