Abstract: Provided in one embodiment of the present specification is a method for user equipment (UE) for an Internet protocol multimedia subsystem (IMS) voice session. The method can comprise the steps of: establishing an EMS voice session by using a non 3GPP interworking function (N3IWF) or an enhanced packet data gateway (ePDG) through non-3rd generation partnership project (3GPP) access; determining that voice is not supported on a current NG-RAN on the basis of that the UE must moves the IMS voice session to a 3GPP access; and handing over a protocol data unit (PDU) session for the IMS voice session of the non-3GPP access to an evolved packet core (EPC) of the 3GPP access on the basis of the determination.

Abstract: One disclosure of the present specification provides a method for performing, by relay UE, communication related to a configuration update. The method comprises the steps of: receiving, from a network node, a configuration update command message including information requesting to perform a registration procedure; and transmitting, to the network node, a response message to the configuration update command message, wherein the response message includes information requesting to maintain a NAS signaling connection between the relay UE and the network node.

Abstract: It is disclosed a method for managing a PDU session in a wireless communication system and an apparatus for supporting the same. Particularly, a method for performing handover of a User Equipment (UE) performed by a source Radio Access Network (RAN) that includes a processor, a memory and a communication module in a wireless communication system may include determining to initiate handover to a target RAN; and transmitting a Handover Required message to a source Access and Mobility Management Function (AMF), and the handover is a handover in a case that there is no interface between the RANs or AMF change is required, and the Handover Required message includes a PDU session Identifier (ID) of an activated Protocol Data Unit (PDU) session.

Abstract: One disclosure of the present specification provides a method for operating in relay user equipment (UE). The method may comprise the steps of: receiving a communication request message directly from a first remote UE; performing a procedure for establishing an access and mobility management function (AMF) entity and a protocol data unit (PDU) session; and storing mapping information between an identifier of a PC5 link with the first remote UE and an identifier of the PDU session on the basis of the PDU session being established for an unstructured PDU session type for unstructured traffic.

Abstract: One disclosure of the present specification provides a method by which a user equipment (UE) performs a protocol data unit (PDU) session establishment procedure for a local area data network (LADN). The method comprises: when a pre-set condition related to an LADN policy is satisfied, transmitting a message requesting an access and mobility management function (AMF) for the LADN policy; receiving, from the AMF, the LADN policy provided by a policy control function (PCF), wherein the LADN policy comprises information about at least one application and information about a LADN data network name (DNN) related to the at least one application; determining a LADN DNN to be used by the UE, on the basis of the LADN policy; and transmitting a PDU session establishment request message related to the determined LADN DNN to the AMF.

Abstract: A disclosure of this specification provides a method for performance measurement of SDF (service data flow), performed by SMF (Session Management Function), the device comprising: receiving a QoS (Quality of Service) rule from a SMF (Session Management Function); performing measurement of performance of a target QoS flow for the SDF, with a UPF (User Plane Function), wherein based on a reflective QoS being not used for the SDF, the QoS rule includes downlink QoS information on the target QoS flow, wherein the target QoS flow is a QoS flow used by the UE to receive a downlink packet for the SDF.

Abstract: A disclosure in the present specification provides a method for user equipment initiating a service request procedure. The method includes a step of the UE receiving a paging message. The UE may be registered to both of a 3rd generation partnership project (3GPP) access and a non-3GPP access within the same PLMN. The paging message may include access type information that is used so as to indicate the non-3GPP access. The method may include a step of initiating a UE triggered service request procedure. The UE triggered service request procedure may be initiated by transmitting a service request message including a list of permitted protocol data unit (PDU) sessions. The service request message may include an empty list of the permitted PDU sessions if there is no PDU sessions that can be reactivated in the 3GPP access.

Abstract: An embodiment of the present invention relates to a method for an access and mobility management function (AMF) transmitting and receiving a signal related to a handover from 5GS to an evolved packet system (EPS) of a user equipment (UE) in a wireless communication system the method comprising a step in which the AMF receives a handover required message from a next-generation radio access network (NG-RAN); a step in which the AMF requests a session management (SM) context to a packet data network gateway+session management function (PGW+SMF); a step of receiving an SM context from the PGW+SMF; and a step in which the AMF transmits a handover command to the NG-RAN, wherein the SM context request is for a PDU session associated with 3GPP access among a plurality of protocol data unit (PDU) sessions.

Abstract: An embodiment provides a method comprising the steps of: receiving, by an NG-RAN, a PDU session-related message including a Qos profile and two or more alternative QoS profiles, which relate to a QoS flow; determining whether the QoS profile can satisfy the QoS flow; transmitting, to an SMF, a first notification indicating that the QoS profile does not satisfy the QoS flow; determining whether the two or more alternative QoS profiles can satisfy the QoS flow; and transmitting, to the SMF, a second notification indicating that the alternative QoS profiles satisfy the QoS flow, wherein the second notification includes information about an alternative Qos profile capable of satisfying the QoS flow, among the two or more alternative QoS profiles.

Abstract: Disclosed in the present specification is a method by which a user equipment (UE) performs access control. The method can comprise the steps of: transmitting a protocol data unit (PDU) session establishment or modification request message; and receiving a PDU session establishment or modification rejection message. The rejection message can comprise information on a backoff timer and session network slice selection assistance information (S-NSSAI). The method can comprise the steps of: driving the backoff timer while being linked with the S-NSSAI; and performing access control on the basis of the S-NSSAI.

Abstract: Provided in one disclosure of the present specification is an operation method of a relay user equipment (UE) for a remote UE. The method may comprise a step in which the relay UE receives, from a base station, a radio resource control (RRC) reconfiguration message or an RRC connection reconfiguration message. The RRC reconfiguration message or the RRC connection reconfiguration message may include identification information of a data radio bearer (DRB) shared with the remote UE and information on a protocol data unit (PDU) session which must be deleted or released in the DRB. The method may comprise a step in which an access stratum (AS) layer of the relay UE relays, to a non-access stratum (NAS) layer, information that a user plane (UP) connection of the PDU session was released, on the basis of the received RRC reconfiguration message or the RRC connection reconfiguration message.

Abstract: A method for forwarding a non-access stratum (NAS) message of a user equipment (UE) in a wireless communication system is disclosed. The method includes sending an uplink (UL) NAS message including a session management (SM) message to an access and mobility management function (AMF), and receiving, from the AMF, an indication message indicating that the SM message is unroutable, wherein indication information indicating that the SM message is unroutable is delivered to a SM sublayer of the UE.

Abstract: In one embodiment, an operation method of first user equipment (UE) in a wireless communication system comprises the steps in which the first UE: derives a plurality of PC5 quality of service (QoS) parameters for each of a plurality of services; and allocating a PC5 QoS flow identifier (PFI) to each of the plurality of services on the basis of the plurality of PC5 QoS parameters, wherein, even when the same PC5 QoS parameter is derived from at least two from among the plurality of services, different PFIs are respectively allocated to the at least two services.

Abstract: One disclosure of the present specification provides a method for performing, by relay UE, communication related to PS Data Off. The method may comprise the steps of: receiving a direct communication request message from remote UE, wherein the direct communication request message includes PS Data Off status information of the remote UE; determining whether or not to establish a protocol data unit (PDU) session for the remote UE, on the basis of the PS Data Off status information of the remote UE; and transmitting a PDU session establishment request message to a network node, on the basis of the determination to the establishing of the PDU session for the remote UE.

Abstract: One disclosure of the present specification provides a method by which an AMF node of a first network performs communication on the basis of a plurality of SIMs. The method comprises the steps of: receiving a registration request message from a terminal through a base station of the first network; receiving, from an SMF node of the first network, a first message including information requesting the activation of a PDU session of the terminal; receiving a second message that includes caller's ID information related to downlink data; and transmitting, to the terminal, a paging message or a non-access stratum (NAS) notification message including the caller's ID information through the base station of the first network.

Abstract: An embodiment of the present disclosure provides a method for transmitting or receiving a signal relating to a PDU session of a UE in a wireless communication system, the method includes the steps of: transmitting, by a UE in a RRC inactive state, a RRC message for resuming to a base station; and receiving, by the UE, information indicating release of a resource from the base station in response to the RRC message for resuming, wherein the release of the resource is caused by the deactivation of a PDU session of the UE.

Abstract: One disclosure of the present specification provides a method for an SMF node to perform authentication. The method may include the steps of: receiving, from a relay UE, a Remote UE report message related to a Remote UE connected to the relay UE; transmitting a request message to a UDM node or an AMF node on the basis of the Remote UE report message including an SUCI of the remote unit; receiving a response message, including an SUPI of the Remote UE, from the UDM node or the AMF node; and transmitting an authentication request message, requesting authentication for the Remote UE, to an authentication server.

Abstract: According to the present specification, disclosed is a method for preventing the transmission of a negative response when an AF subscribed to a notification service for a user plane management event receives a notification from an SMF, and when it is determined that a subsequent action according to the notification cannot be processed immediately but can be processed after a predetermined period of time.

Abstract: A disclosure of the present specification provides a method for a terminal to perform communication related to an IMS. The method may comprise the steps of: receiving, by an NAS layer of a terminal, a first request message from an IMS layer of the terminal, wherein the first request message includes information related to IMS signaling for a non-service attempt and information about a first access category among a plurality of access categories related to an IMS service, and the IMS signaling for the non-service attempt is signaling which does not request the IMS service; and transmitting, by the NAS layer of the terminal, a second request message including the information about the first access category to an RRC layer of the terminal.

Abstract: One disclosure of the present specification provides a method for operating in relay user equipment (UE). The method may comprise the steps of: receiving a communication request message directly from a first remote UE; performing a procedure for establishing an access and mobility management function (AMF) entity and a protocol data unit (PDU) session; and storing mapping information between an identifier of a PC5 link with the first remote UE and an identifier of the PDU session on the basis of the PDU session being established for an unstructured PDU session type for unstructured traffic.