Abstract: A method for obtaining an identifier of a terminal device includes a key management network element receiving, from a first terminal device, a first key request including a first identifier, where the first identifier is an anonymous identifier or a temporary identifier of a second terminal device. The key management network element sends, to a unified data management network element, a first request including the first identifier. The unified data management network element determines a SUPI of the second terminal device based on the first identifier, and sends, to the key management network element, a first response including the SUPI. In response to an authorization check performed on the second terminal device based on the SUPI succeeds, the key management network element sends a first key response to the first terminal device, where the first key response includes a secure communication parameter.

Abstract: Example communication methods and apparatus are described. One example communication method includes receiving first indication information by a first network element from a second network element, where the first indication information is used to indicate that a current condition supports establishment of a session of a first network for a terminal apparatus. The first network element obtains first quality of service (QoS) control information of a first session of the terminal apparatus after receiving the first indication information, where the first session is a session established by the terminal apparatus by using a second network. The first network element sends the first QoS control information to the second network element.

Abstract: A communication method includes receiving, by an access network (AN) node, indication information from a mobility management device. The indication information is indicative of a security policy of a quality of service (QoS) flow. The method also includes obtaining, by the access network node based on the indication information, security information of a radio bearer corresponding to the QoS flow. The security information is indicative of a security policy of the radio bearer. The method further includes sending, by the access network node, an identifier of the radio bearer and the security information of the radio bearer to a terminal.

Abstract: A communications method includes determining a session management function entity based on at least one of a data network name, slice information, and an application function service identifier, and sending a first message to the session management function entity, where the first message is used to subscribe to a terminal event, the first message includes service description information, and the service description information is used to indicate a service corresponding to the terminal event.

Abstract: This application provides a method and an apparatus for invoking an application programming interface (API), to determine a target exposing function network element used to invoke an API. The method includes: A first network element obtains routing information of an API, where the routing information is used to indicate a route for invoking the API, and the API is provided by a first exposing function network element and a second exposing function network element; the first network element obtains invocation parameter information of the API, where the invocation parameter information is used to handle the API; and the first network element determines a target exposing function network element in the first exposing function network element and the second exposing function network element based on the routing information and the invocation parameter information.

Abstract: A first network device receives a group selection request, where the group selection request is used to instruct to set a first MCPTT group as a selected MCPTT group for a first MCPTT user; and the first network device sends, according to the group selection request, information about the first MCPTT group to first UE used by the first MCPTT user, so that the first network device can set the first MCPTT group as a selected MCPTT group for the first MCPTT user.

Abstract: Embodiments of the present application relate to the wireless communications field, and in particular, to a session management method and a session management network element. The session management method includes: receiving, by a first control plane network element, a user equipment UE context response message from a second control plane network element, where the UE context response message carries a first session message, and the first session message is a pending session message; and sending, by the first control plane network element, a second session message to user equipment according to the UE context response message. According to the session management method and the session management network element in the embodiments of the present application, a session can be managed in a scenario in which a control plane connection of user equipment changes.

Abstract: A visible-light-photocatalyzed composite light-transmitting concrete contains several bundles of optical fibers, the optical fibers are coated with a protective layer on their outer surface, the protective layer contains a visible light photocatalyst, and the concrete has several gas-permeable pores. Such concrete is prepared by mixing a visible light photocatalyst and a light-transmitting glue, applying the mixture to the surface of optical fibers to form a protective layer, and using optical fibers in the concrete. The resulting concrete has dual properties of light transmittance and photocatalytic oxidation of gas-phase pollutants under visible light irradiation. The visible-light-photocatalyzed composite light-transmitting concrete significantly breaks through the limitation of photocatalytic concrete to light sources, so that gas-phase pollutants can be removed under visible light irradiation through photocatalysis of light-transmitting concrete.

Abstract: This application discloses a multicast session establishment method and a network device, and relates to the field of wireless communication technologies, to implement establishment of a multicast session based on a network architecture that has been deployed by an operator. In one example, when the multicast session is established, policy control, for example, quality of service QoS control, of the multicast session may be completed via a policy control network element or a session management network element in the network architecture that has been deployed by the operator.

Abstract: Disclosed is an AMBR control method, device, and system, so that a quality of service (QoS) control mechanism can be used to control use of resources in a network slice by a terminal device. The method includes: a mobility management network element obtaining M pieces of single network slice selection assistance information (S-NSSAI) corresponding to a terminal device and a first slice-AMBR corresponding to each piece of S-NSSAI in the M pieces of S-NSSAI; and sending the M pieces of S-NSSAI and the first slice-AMBR corresponding to each piece of S-NSSAI to an access network device, where the first slice-AMBR corresponding to each piece of S-NSSAI is used to determine a second slice-AMBR corresponding to the S-NSSAI, and the second slice-AMBR corresponding to each piece of S-NSSAI is used to control an aggregate bit rate of non-guaranteed bit rate non-GBR QoS flows in a network slice indicated by the S-NSSAI.

Abstract: A communication method includes receiving, by a policy control network element executed by a processor, first information. The first information is service information or a traffic steering requirement. The traffic steering requirement includes at least one service function. The communication method also includes obtaining, by the policy control network element, first traffic steering policy information from a first network element based on the first information. The first traffic steering policy information indicates network elements corresponding to the at least one service function and a sequence in which service data passes through the network elements corresponding to the at least one service function.

Abstract: A quality of service (QoS) control method and a device, where the method includes: a session management function (SMF) entity obtaining service data flow (SDF)-level QoS control information; the SMF entity sending the SDF-level QoS control information to a terminal; and the terminal performing QoS control on an uplink data packet based on the SDF-level QoS control information, or the terminal deleting the SDF-level QoS control information. The terminal can perform the QoS control on the uplink data packet based on the SDF-level QoS control information.

Abstract: The present disclosure relates to user plane information reporting methods and apparatus. In one example method, a session management network element obtains parameter information, and initiates establishment of a dedicated tunnel between a first communications apparatus and a second communications apparatus, where the parameter information indicates the first communications apparatus to report user plane information when a reporting condition is met. The session management network element sends a first rule to the first communications apparatus, where the first rule indicates the first communications apparatus to send a packet to the second communications apparatus through the dedicated tunnel when the reporting condition is met.

Abstract: The present application relates to broadcast bearer management methods and devices. One example method includes receiving, by a first bearer management server (BMS), a first message sent by a service server, where the first message includes a group identifier of a service group, determining, by the first BMS, a first broadcast bearer for the service group based on the first message, and sending, by the first BMS, a second message to the service server, where the second message carries user plane information of the first broadcast bearer.

Abstract: A method, an apparatus, and a system for managing a background data transfer policy, such that a policy control function network element can obtain a background data transfer policy corresponding to a terminal. The method includes: A first policy control function network element receives a first message. The first message carries a first identifier, and the first identifier may be a background data transfer reference identifier or an application function identifier. Then, the first policy control function network element sends a second message to a first data storage network element, facilitating obtaining of a background data transfer policy. The second message carries the first identifier. Finally, the first policy control function network element receives a third message from the first data storage network element. The third message includes a first background data transfer policy corresponding to the first identifier.

Abstract: This application discloses a communications method and apparatus. The method includes: sending, by a session management network element, first indication information when the session management network element determines, based on first information, to establish a first low-latency service flow for a session; and the first indication information is used to indicate to set the session to an always-on session. According to solutions of this application, when determining, based on the local configuration information, the subscription data, and the QoS parameter, to establish the low-latency service flow, the session management network element flexibly indicates a terminal apparatus to set the session to the always-on session. This avoids a resource waste caused by setting the session to the always-on session all the time, and avoids a transmission latency caused when the session is not set to the always-on session in time, so that resource utilization and transmission efficiency are improved.

Abstract: A quality of service (QoS) control method and a device, where the method includes: a session management function (SMF) entity obtaining service data flow (SDF)-level QoS control information; the SMF entity sending the SDF-level QoS control information to a terminal; and the terminal performing QoS control on an uplink data packet based on the SDF-level QoS control information, or the terminal deleting the SDF-level QoS control information. The terminal can perform the QoS control on the uplink data packet based on the SDF-level QoS control information.

Abstract: This specification discloses a communication method, and a system. The method includes: receiving, by a first control network element, analysis information of a network data analytics network element NWDA, and generating a policy based on the analysis information; sending, by the first control network element, the policy to a second control network element, where execution of the policy is controlled by the second control network element; receiving, by the first control network element, an execution result of the policy that is sent by the second control network element, and determining, based on the execution result, whether the analysis information is invalid; and sending, by the first control network element, an invalidity notification message to the NWDA when the first control network element determines that the analysis information is invalid, where the invalidity notification message is used to instruct the NWDA to generate new analysis information.

Abstract: The present disclosure relates to communication methods and apparatus. One example method includes receiving, by a target service entity, a first request message from a first participating service entity, and sending, by the target service entity, a first response message to the first participating service entity. The first request message comprises an identity of a target multicast bearer and a group identity of a terminal group. The first response message is used to instruct the first participating service entity to use the target multicast bearer to send service data of the terminal group.

Abstract: This application provides a network node selection method and apparatus. An SMF network element obtains transmission capability information of an access network device, and selects, for a terminal device based on the transmission capability information of the access network device, a UPF network element that supports at least one transmission capability included in the transmission capability information. In this process, the SMF network element obtains a transmission capability of the access network device, and selects the UPF network element based on the transmission capability of the access network device. The selected UPF network element supports the transmission capability used by the access network device, so that data can be successfully transmitted between the access network device and the UPF network element. Therefore, a data transmission success rate is improved.