Section: 16.11 Minimization of Service Interruption
Content: In case of a disaster, a radio access network can experience outage, which can result in that UEs belonging to the network experience service interruptions. For this scenario, another network not affected by the disaster, which during non-disaster situations is considered by the UEs as a forbidden network, can allow roaming of the UEs belonging to the network experiencing such disaster service interruptions. Such roaming is referred to as disaster roaming. This is further described in clause 5.40 of TS 23.501[ System architecture for the 5G System (5GS) ]  [3] and 3.10 of TS 23.122[ Non-Access-Stratum (NAS) functions related to Mobile Station (MS) in idle mode ]  [47]. To allow such disaster roaming, a cell can broadcast a list of PLMNs with disaster conditions for which disaster roaming is offered. Disaster roaming service is provided only for the area that covers the area with disaster condition. Further, to be able to control the load that disaster roaming UEs put on a cell, the cell can broadcast access control parameters applicable specifically for disaster roaming UEs. Access attempts of disaster roaming UEs are based on Access Identity 3. The network can for example set the access control parameters for Access Identity 3 so that access attempts of disaster roaming UEs are more likely to be barred compared to non-disaster roaming UEs.