The 5G RAN includes a sub-state called “RRC Inactive”. In this state, air interface resources are released but the device’s context remains on the last serving gNB. If the last serving gNB receives downlink data from the UPF, or signalling from the AMF, it pages in the cells corresponding to the RNA (RAN Based Notification Area). This can include sending Paging to neighbour gNB(s), which belong to the RNA, across the Xn interface. Whilst in the RRC Inactive state, the device will perform a RNA update procedure if it moves to a cell which is not part of the current RNA assigned.