Abstract: A method for a protocol data unit (PDU) session includes a step of a first core network device obtaining a first message from a first server. The first core network device generates a first parameter based on the first message. A terminal device obtains a measurement result based on the first parameter and sends the measurement result to the first core network device. The first core network device obtains a second parameter based on the measurement result, and the second core network device configures the second parameter to dynamically adjust the PDU session based on location or time information with reference to the second parameter.

Abstract: This application discloses a paging indication method and an apparatus. The method includes: A UE obtains first indication information, where the first indication information indicates whether a core network device supports a paging cause value; and receives a first paging message, where the first paging message includes first information corresponding to the UE, and the first information does not include a first field indicating the paging cause value; and when the first indication information indicates that the core network device supports the paging cause value, the first information indicates the paging cause value. According to the method provided in this application, the UE can explicitly learn whether the paging cause value is indicated in information that is in a paging message and that corresponds to the UE.

Abstract: An inter-communications-system moving method includes determining, by user equipment UE, whether a first session exists in a first communications system, where the first session is capable of being transferred from the first communications system to a second communications system; and sending, by the UE, a first message to a first core network device of the second communications system when determining that the first session exists, where the first message is used to establish a second session in the second communications system, and the second session corresponds to the first session.

Abstract: Embodiments of the present application relate to the field of communications technologies, and provide a session management method and system, and a terminal. The method includes: when user equipment UE has a first protocol data unit PDU session, sending, by the UE, a service request message to an access and mobility management function AMF entity; receiving, by the UE, a first message sent by the AMF entity; and determining, by the UE based on the first message, to re-establish or modify the first PDU session. In the embodiments of the present invention, the UE sends the service request message to the AMF entity, and then the AMF entity sends, to the UE, the first message used to determine to re-establish or modify the first PDU session.

Abstract: A method includes: receiving, by a network data analytics function entity, a first message that is sent by an application function entity and that includes a measurement event and an identity ID of an application; obtaining a first measurement parameter based on the measurement event; receiving, by the network data analytics function entity, a notification message that is sent by a terminal and that is used to indicate the network data analytics function entity to perform data collection on the application; sending a second message including the ID of the application and the first measurement parameter to a policy control function entity, and requesting the policy control function entity to send the second measurement parameter to the terminal.

Abstract: A protocol data unit (PDU) type setting method, a user equipment (UE) policy setting method, and a related entity, where the PDU type setting method includes: setting, by UE, a requested PDU type of a PDU session in a process of establishing the PDU session, where the requested PDU type of the PDU session is set by the UE based on a first condition, the first condition includes an Internet Protocol (IP) version corresponding to an application, and the application is associated with the PDU session. In the embodiments of the present disclosure, the requested PDU type of the PDU session can be consistent with a PDU type requested by the application, such that the application can normally perform communication.

Abstract: This application provides a communication method and apparatus. The communication method and apparatus may be applied to an Internet of Vehicles system, a V2X system, and a device-to-device communication system. The method includes: obtaining first indication information and second indication information, where the first indication information indicates a first periodicity for receiving signaling and/or data and a second periodicity for not receiving signaling and data, and the second indication information indicates a first time unit for receiving signaling and/or data and a second time unit for not receiving signaling and data in the first periodicity; and determining to receive signaling and/or data in the first time unit.

Abstract: A data transmission method includes obtaining a user equipment route selection policy (USRP) rule parameter of a started application, establishing a first protocol data unit (PDU) session corresponding to the started application with a network device through the modem module when no PDU session parameter matching the URSP rule parameter exists in the mapping table, adding an interface name of the first PDU session to the routing table, adding a mapping relationship between the session parameter of the first PDU session and the interface name of the first PDU session to the mapping table, and routing to-be-transmitted data of the started application to the first PDU session by using the interface name of the first PDU session.

Abstract: A wireless communication method is applied to a communications system including a UE, a RAN, a first core network entity, and at least one network slice. The wireless communication method includes: establishing, by the first core network entity, a signaling connection to the UE; receiving, by the first core network entity and from the UE via the signaling connection, network slice information and a non-access stratum NAS message; determining, by the first core network entity and based on the network slice information, a target network slice from the at least one network slice, where the target network slice includes a second core network entity, and the UE performs NAS communication with the second core network entity using the RAN and the first core network entity; and sending, by the first core network entity, the NAS message to the second core network entity.

Abstract: A registration method, a session establishment method, a terminal, and an access and mobility management function (AMF) entity, where the method includes: sending, by a terminal, a first message to the AMF entity, where the first message includes first information, first network slice selection information, and second network slice selection information, the first information includes information for requesting to establish a protocol data unit (PDU) session, the first network slice selection information is used by the AMF entity to select a first session management function (SMF) entity, and the second network slice selection information is used by the AMF entity to select a second SMF entity; and receiving, by the terminal, a second message from the AMF entity, where the second message includes second information, and the second information includes PDU session establishment accept information.

Abstract: An identifier allocation method includes receiving, by a first core network device, a first request from a terminal device, allocating, by the first core network device, a first capability information identifier, and sending, by the first core network device, a first response to the terminal device, where the first response carries the first capability information identifier.

Abstract: A communication path switching method and device, where the method includes receiving, by a first base station, a first message from a first terminal, where the first message requesting to switch the first terminal from a first path for independently accessing a network to a second path for accessing the network using a second terminal, and the first base station serves the first terminal, determining, by the first base station according to the first message, a second base station serving the second terminal, obtaining, by the first base station, configuration information from the second base station, where the configuration information enabling the first terminal to access the network using the second terminal, and sending, by the first base station, the configuration information to the first terminal. Therefore, communication path switching for different complex application scenarios can be implemented.

Abstract: A method and an apparatus for signal synchronization are disclosed. The method for signal synchronization includes: A self-synchronizing first terminal device broadcasts first synchronization information, determines whether the first terminal device and a second terminal device have implemented signal synchronization when receiving second synchronization information sent by the second terminal device, and determines, based on a determining result, whether to synchronize with the second terminal device. This reduces a probability of communication interruption caused by synchronization source switching by the first terminal device after the second terminal device performs synchronization by using the first terminal device as a synchronization source. The method for signal synchronization may be applied to scenarios such as the intelligent driving, intelligent connected vehicles, and internet of vehicles.

Abstract: Embodiments of the present application provide user equipment (UE), a first core network entity, and a second core network entity, the first core network entity executes steps that include: establishing a signaling connection to the UE; receiving network slice information and a non-access stratum NAS message that are sent by the UE over the signaling connection; determining a target network slice from the at least one network slice based on the network slice information, wherein the target network slice comprises a second core network entity, and the UE performs NAS communication with the second core network entity by using the RAN and the first core network entity; and sending the NAS message to the second core network entity.

Abstract: An inter-network interworking method, an apparatus, and a system are provided, and relate to the field of communication technologies, to ensure that a service is not interrupted when a terminal moves from a second network to a third network. The method includes: When the terminal supports a NAS capability of the third network and/or a network name corresponding to the terminal supports interworking between the second network and the third network, a second access management network element sends a session management request including a session identifier to a first session management network element that supports interworking of the terminal among a first network, the second network, and the third network. The second access management network element receives, from the first session management network element, a session management response including a session context of the terminal in the third network.

Abstract: Embodiments of this application relate to the field of communications technologies, and disclose a relay device selection method, and a user equipment, so that UE can select and update with an allowed S-NSSAI of the UE. The method may include: obtaining by UE, M pieces of first indication information, each indicates one allowed network slice of the UE; receiving by the UE, first messages sent by L relay devices, comprising N pieces of second indication information, wherein each indicates one allowed network slice of the relay device; and selecting by the UE, a random first relay device as a target relay device based on the M pieces of first indication information and the L pieces of first messages.

Abstract: A communication path switching method and device, where the method includes receiving, by a first base station, a first message from a first terminal, where the first message requesting to switch the first terminal from a first path for independently accessing a network to a second path for accessing the network using a second terminal, and the first base station serves the first terminal, determining, by the first base station according to the first message, a second base station serving the second terminal, obtaining, by the first base station, configuration information from the second base station, where the configuration information enabling the first terminal to access the network using the second terminal, and sending, by the first base station, the configuration information to the first terminal. Therefore, communication path switching for different complex application scenarios can be implemented.

Abstract: A session management method by a terminal in which a network initiates a session deactivation procedure to deactivate one or more sessions of a terminal. After the terminal in an inactive mode establishes an RRC connection to a new second base station, the second base station indicates, through RRC connection reconfiguration, the terminal to delete related information of the to-be-deactivated session, or the second base station uses an RRC connection resume response message to carry an identifier of the one or more to-be-deactivated sessions, and the terminal deletes session-related information corresponding to the identifier of the one or more to-be-deactivated sessions. In this way, the terminal is enabled to process the related information of the to-be-deactivated session in a timely manner.

Abstract: Embodiments of this application relate to the field of communications technologies, and disclose a relay device selection method, and a user equipment, so that UE can select and update with an allowed S-NSSAI of the UE. The method may include: obtaining by UE, M pieces of first indication information, each indicates one allowed network slice of the UE; receiving by the UE, first messages sent by L relay devices, comprising N pieces of second indication information, wherein each indicates one allowed network slice of the relay device; and selecting by the UE, a random first relay device as a target relay device based on the M pieces of first indication information and the L pieces of first messages.

Abstract: Embodiments of the present application relate to the field of communications technologies, and provide a session management method and system, and a terminal. The method includes: when user equipment UE has a first protocol data unit PDU session, sending, by the UE, a service request message to an access and mobility management function AMF entity; receiving, by the UE, a first message sent by the AMF entity; and determining, by the UE based on the first message, to re-establish or modify the first PDU session. In the embodiments of the present invention, the UE sends the service request message to the AMF entity, and then the AMF entity sends, to the UE, the first message used to determine to re-establish or modify the first PDU session.