Method for supporting service continuity when disaster situation ends, and device supporting same
Provided are a method for supporting service continuity when a disaster situation ends, and a device supporting same. A user equipment (UE) receives, from a disaster roaming PLMN, a configuration update command message including information indicating that a disaster condition of a home PLMN (HPLMN) has ended. The UE waits until a service that is being received from the disaster roaming PLMN ends, and performs, after the service that is being received from the disaster roaming PLMN ends, a procedure of deregistration from the disaster roaming PLMN on the basis of information indicating that the disaster condition of the HPLMN has ended.
1. A method performed by a user equipment (UE) adapted to operate in a wireless communication system, the method comprising;
determining that a first Public Land Mobile Network (PLMN) is in a disaster condition;
based on the first PLMN being in the disaster condition, registering with a second PLMN and receiving a disaster roaming service from the second PLMN;
based on the disaster condition in the first PLMN being over, receiving a Configuration Update Command message including a configuration update indication Information Element (IE) with a registration request bit set to “registration requested” from an Access and mobility Management Function (AMF) of the second PLMN;
transmitting a Registration Request message to the AMF of the second PLMN;
receiving a Registration Reject message from the AMF of the second PLMN in response to the Registration Request message; and
selecting the first PLMN and performing a registration with the first PLMN.
2. The method of claim 1 , wherein the method further comprises transmitting a Configuration Update Complete message in response to the Configuration Update Command message to the AMF of the second PLMN.
3. The method of claim 1 , wherein the method further comprises including the second PLMN in a forbidden PLMN list.
4. The method of claim 1 , wherein the method further comprises updating an internally set disaster situation being ended.
5. The method of claim 1 , wherein a Non-Access Stratum (NAS) signaling connection release is not performed regardless of the registration requested bit set to “registration requested”.
6. The method of claim 1 , wherein the UE communicates with at least one of a mobile device, a network and/or an autonomous vehicle other than the UE.
7. The method of claim 1 , wherein the Registration Reject message includes a Mobility Management (MM) cause value informing that the disaster roaming service cannot be provided in the second PLMN.
8. A user equipment (UE) adapted to operate in a wireless communication system, the UE comprising:
at least one transceiver;
at least one processor; and
at least one memory operably connectable to the at least one processor and storing instructions that, based on being executed by the at least one processor, perform operations comprising:
determining that a first Public Land Mobile Network (PLMN) is in a disaster condition;
based on the first PLMN being in the disaster condition, registering with a second PLMN and receiving, via the at least one transceiver, a disaster roaming service from the second PLMN;
based on the disaster condition in the first PLMN being over, receiving, via the at least one transceiver, a Configuration Update Command message including a configuration update indication Information Element (IE) with a registration request bit set to “registration requested” from an Access and mobility Management Function (AMF) of the second PLMN;
transmitting, via the at least one transceiver, a Registration Request message to the AMF of the second PLMN;
receiving, via the at least one transceiver, a Registration Reject message from the AMF of the second PLMN in response to the Registration Request message; and
selecting the first PLMN and performing a registration with the first PLMN.
9. The UE of claim 8 , wherein the operations further comprise transmitting a Configuration Update Complete message in response to the Configuration Update Command message to the AMF of the second PLMN.
10. The UE of claim 8 , wherein the operations further comprise including the second PLMN in a forbidden PLMN list.
11. The UE of claim 8 , wherein the operations further comprise updating an internally set disaster situation being ended.
12. The UE of claim 8 , wherein the Registration Reject message includes a Mobility Management (MM) cause value informing that the disaster roaming service cannot be provided in the second PLMN.
13. An Access and mobility Management Function (AMF) of a second Public Land Mobile Network (PLMN) adapted to operate in a wireless communication system, the AMF comprising:
at least one processor; and
at least one memory operably connectable to the at least one processor and storing instructions that, based on being executed by the at least one processor, perform operations comprising:
performing a registration with a User Equipment (UE) for disaster roaming;
providing a disaster roaming service to the UE;
determining that a disaster condition in a first PLMN is over;
based on the disaster condition in the first PLMN being over, transmitting a Configuration Update Command message including a configuration update indication Information Element (IE) with a registration request bit set to “registration requested” to the UE;
receiving a Registration Request message from the UE; and
transmitting a Registration Reject message to the UE in response to the Registration Request message.