After acknowledgments from the respective VLRs have been received for these steps, the HLR will send a Location Update confirmation back to the serving network, which forwards it to the UE, thereby informing the UE that the location update processing is complete by all parties involved.
[1] A solution was implemented with the Super-Charger realization in an effort to reduce telecommunications signaling traffic.
[1][2] Outdated subscriber information is a concern if the UE does not re-enter the previous visiting network after an extended period of time.
Therefore, visiting networks should implement database maintenance measures to ensure outdated and unused subscriber information is removed.
Typically, when a HLR instructs a subscriber purge (via a Cancel Location message) to a visiting network, the visiting network purges the subscriber information and sends an acknowledgment back to the HLR.
The networks can further cut back on signalling traffic by not returning an acknowledgment, and just having the HLR assume the purge was completed.