Abstract: In a UE configuration update procedure initiated by a network, when the UE is connected to the network via a satellite, one or more forbidden tracking area identities (TAIs) in a 5G system (5GS) forbidden tracking area information element for roaming and/or regional provision of service are included and transmitted in a configuration update command message transmitted by a 5G core network to the UE to provide an appropriate procedure for updating a tracking area identity (TAI) list stored in the UE while the UE in a 5GMM connected mode maintains a registered state.

Abstract: A UE capable of performing communication via a satellite receives a wait range via a first satellite from a first PLMN. In a case that the UE becomes able to perform communication via a second satellite connected to the first PLMN after becoming unable to perform communication via the first satellite, the UE selects the first PLMN, generates a wait timer based on the wait range, and starts a timer using the wait timer. In a case that an emergency call is made during the timer running, the UE stops the timer and performs a registration procedure for the emergency call. In a case that an emergency call is not made during the timer running, the UE performs the registration procedure after the timer expires.

Abstract: A UE capable of performing communication via a satellite receives a wait range via a first satellite from a first PLMN. In a case that the UE becomes able to perform communication via a second satellite connected to a second PLMN after becoming unable to perform communication via the first satellite, the UE selects the second PLMN, generates a wait timer based on the wait range, and starts a timer using the wait timer. In a case that an emergency call is made during the timer is running, the UE stops the timer and performs a registration procedure for the emergency call. In a case that an emergency call is not made during the timer is running, the UE performs the registration procedure after the timer expires.

Abstract: A unit is provided through an application of a disaster condition to a PLMN in 5GS, the unit being for transmitting and/or receiving a notification in a case that a communication service cannot be provided to a UE and for selecting a roaming destination PLMN by the UE. Provided are a procedure to allow the UE to recognize a state of a certain PLMN and transmit and/or receive information for appropriately selecting a PLMN as a moving destination in a case that a disaster condition applies or no longer applies to the certain PLMN, a method of selecting a PLMN based on information received and stored by the UE through a notification from the PLMN or the like, and a communication unit.

Abstract: A User Equipment (UE) includes transmission and reception circuitry, and a controller, wherein while one or more Tsor-cm timers are running, and upon receiving a new Steering of roaming connected mode control information (SOR-CMCI), the controller sets a Tsor-cm timer value for an associated PDU session or service to a timer value in the new SOR-CMCI.

Abstract: In a case that user equipment (UE) that has established a communication path for direct C2 communication receives, from a network, a PDU session release command message for revoking authentication and/or authorization of the communication path for the direct C2 communication or a PDU session modification command message, the UE can indicate an appropriate cause value in the procedure of releasing the communication path for the direct C2 communication.

Abstract: A unit is provided through an application of a disaster condition to a PLMN in 5GS, the unit being for transmitting and/or receiving a notification in a case that a communication service cannot be provided to a UE and for selecting a roaming destination PLMN by the UE. Provided are a procedure to allow the UE to recognize a state of a certain PLMN and transmit and/or receive information for appropriately selecting a PLMN as a moving destination in a case that a disaster condition applies or no longer applies to the certain PLMN, a method of selecting a PLMN based on information received and stored by the UE through a notification from the PLMN or the like, and a communication unit.

Abstract: A User Equipment (UE) includes a controller. The controller is in automatic network selection mode, and the controller stops a Tsor-cm timer in a case that the controller switched to manual network selection mode and the Tsor-cm timer is running.

Abstract: A terminal apparatus and an apparatus in a core network exchange information indicating maintenance of a PDU session in a procedure for releasing UP resources, and thereby releases the UP resources associated with a specific PDU session while maintaining establishment of the specific PDU session. A terminal apparatus and an apparatus in a core network further exchange information indicating a release of only the UP resources in a procedure for releasing the UP resources, and thereby the terminal apparatus recognizes the release of the UP resources associated with the specific PDU session. In this manner, in order to release the UP resources associated with the specific PDU session while maintaining establishment of the specific PDU session, and to allow the terminal apparatus to recognize the release of the UP resources, a system and a communication control method are provided.

Abstract: A communication measure is provided that causes a PDU session established in a 5GS to return to the PDU session in an original state after the PDU session established in the 5GS is moved (handed over) to an EPS and then moved (handed over) to the 5GS again. In addition, according to the present invention, a communication measure is provided that causes a PDN connection established in the EPS to return to the PDN connection in an original state after the PDN connection established in the EPS is moved (handed over) to the 5GS and then again moved (handed over) to the EP. In addition, according to the present invention, a communication measure is provided that allows smooth mobility of the UE in an idle mode between the 5GS and the EPS. Further, a communication measure is provided that performs a handover between the 5GS and the EPS smoothly.

Abstract: A communication measure is provided that causes a PDU session established in a 5GS to return to an original state of the PDU session in a case that the PDU session is moved (handed over) to an EPS and then moved (handed over) to the 5GS again. In addition, according to the present invention, a communication measure is provided that causes a PDN connection established in the EPS to return to the PDN connection in an original state after the PDN connection established in the EPS is moved (handed over) to the 5GS and then again moved (handed over) to the EP. In addition, according to the present invention, a communication measure is provided that allows smooth mobility of the UE in an idle mode between the 5GS and the EPS. This allows a communication measure that performs a handover between the 5GS and the EPS smoothly to be provided.

Abstract: In a case that a network (NW) applies a plurality of congestion controls, various kinds of congestion control identification information along with a back-off timer (Session Management (SM) timer) are notified such that a terminal apparatus (UE) can apply a congestion control expected by the NW. Alternatively, in a case that the UE receives an NW-initiated SM request with the back-off timer activated, the UE is allowed to identify an SM timer intended by the NW-initiated SM request. Alternatively, in a case that the UE receives the NW-initiated SM request with the back-off timer activated, the UE is allowed to modify the association of the activated back-off timer and the congestion control to be applied. Thus, a communication control method for the terminal to apply the congestion control expected by the NW in the congestion controls applied by the NW in 5G congestion control that applies a plurality of congestion controls is provided.

Abstract: In a case that a network (NW) applies a plurality of congestion controls, various kinds of congestion control identification information along with a back-off timer (Session Management (SM) timer) are notified such that a terminal apparatus (UE) can apply a congestion control expected by the NW. Alternatively, in a case that the UE receives an NW-initiated SM request with the back-off timer activated, the UE is allowed to identify an SM timer intended by the NW-initiated SM request. Alternatively, in a case that the UE receives the NW-initiated SM request with the back-off timer activated, the UE is allowed to modify the association of the activated back-off timer and the congestion control to be applied. Thus, a communication control method for the terminal to apply the congestion control expected by the NW in the congestion controls applied by the NW in 5G congestion control that applies a plurality of congestion controls is provided.

Abstract: A notification is made of information in one PDU session establishment procedure to a terminal apparatus, the information being associated with information for identifying one NW slice that is a target of congestion control and the information for identifying another NW slice associated, to prevent a PDU session establishment procedure using information for identifying multiple NW slices at a time. As a method for interpreting the information for identifying the other NW slice associated, two implementation schemes are defined that use explicit notifications from a network and rules configured for the terminal apparatus. In a case that NW slice based congestion control is applied, information for identifying the NW slice to which establishment of a PDU session is allowed is notified as an exception.

Abstract: A terminal apparatus and an apparatus in a core network implement a service request procedure for re-establishing UP resources that have been released. In the service request procedure, re-establishment of the UP resources for multiple PDU sessions is implemented. With this configuration, a UP resource associated with a specific PDU session is allowed to be released while maintaining the specific PDU session established, and a system and a communication control method that allow the UP resource to be released are provided.

Abstract: In an IMS emergency call connection of a call which a user equipment cannot recognize as an emergency call, a user equipment transmits to an IMS an IMS emergency call connection signal of the call which the user equipment cannot recognize as the emergency call, and in a case that a reject or redirection message indicating an emergency call connection is received from the IMS, the user equipment determines whether to transmit the IMS emergency call connection signal again to a core network to which the user equipment is connected or whether to transmit the IMS emergency call connection signal again to another core network in the same PLMN. Accordingly, a user equipment, a core network apparatus, a control method to be performed by an IMS apparatus, and the like are provided for the user equipment to connect to a network suitable for an emergency call service in the 5th generation (5G) mobile communication system, which is a next-generation mobile communication system.

Abstract: Provided are, for example: a communication controller configured to establish a suitable session for a terminal apparatus and a network apparatus that are connected to a wide variety of multiple access networks; a user-data communication controller that is suitable for a terminal apparatus and a network apparatus establishing a session via multiple access networks. Hence, the NextGen has studied the optimization of session management for the mobile communication service between a terminal apparatus and a network apparatus. Provided is a communication controller suitable for a terminal apparatus and network apparatus supporting the connection to a wide variety of multiple access networks.

Abstract: Provided is a communication measure for registering information about a terminal apparatus in various apparatuses, such as a control apparatus and a terminal apparatus, included in a communication system in which a protocol used for registration management or registration information management for a mobile communication service is shared, based on the states of the various apparatuses. Also provided is a communication control measure for updating the information about the terminal apparatus registered in the various apparatuses. Thus, there are provided, in a communication system in which a protocol used for registration management or registration information management for a mobile communication service is shared, a measure for registration management based on the states of various apparatuses included in the communication system, such as a control apparatus and a terminal apparatus, and a realization measure for determining post-registration behavior.

Abstract: Provided are a terminal apparatus capable of connecting to various core networks, a communication controller suitable for a device in a network connectable to the terminal apparatus, a communication controller for changing a core network to which the terminal apparatus is connected, a communication controller for switching a session established by the terminal apparatus to a session with another core network, and the like. This provides the terminal apparatus supporting a switch of connectivity between multiple core networks, and a communication controller suitable for the device in the network connectable with the terminal apparatus.

Abstract: A terminal apparatus and an apparatus in a core network exchange information indicating maintenance of a PDU session in a procedure for releasing UP resources, and thereby releases the UP resources associated with a specific PDU session while maintaining establishment of the specific PDU session. A terminal apparatus and an apparatus in a core network further exchange information indicating a release of only the UP resources in a procedure for releasing the UP resources, and thereby the terminal apparatus recognizes the release of the UP resources associated with the specific PDU session. In this manner, in order to release the UP resources associated with the specific PDU session while maintaining establishment of the specific PDU session, and to allow the terminal apparatus to recognize the release of the UP resources, a system and a communication control method are provided.