Abstract: This application provides a communication method, apparatus, and system for a voice service. The method includes: A session management network element determines that a terminal device is to be handed over from a first network to a second network. The session management network element waits until a first moment to send a request message to a mobility management network element in the second network, where the request message is used to request to set up a first bearer for a voice service of the terminal device.

Abstract: An event report sending method in which a session management network element receives an event notification request from a policy control network element, where the event notification request includes an event identifier and a notification address for receiving an event report of an event report receiving network element, and where the event report receiving network element is an application function network element or a network exposure function network element. The session management network element sends, a first message comprising the event identifier and the notification address to a user plane network element, where the first message indicates to the user plane network element to send, to the notification address, a first event report corresponding to the event identifier. Thus, the network exposure function network element sends the received first event report to the application function network element, such that the application function network element obtains the event report.

Abstract: A communication method and a communication apparatus are disclosed. A control network element receives first information from a user equipment (UE), where the first information includes multi-3GPP access request indication information or change indication information. The control network element determines, based on the first information, whether to allow the UE to establish a multi-3GPP access session. The multi-3GPP access request indication information indicates that the UE requests to establish the multi-3GPP access session, and the change indication information indicates that the UE allows the control network element to change from establishing a dual access session or a single access session to establishing the multi-3GPP access session. In this way, the control network element determines whether the UE can support a plurality of 3GPP connections at the same time, so that the UE can establish the multi-3GPP access session of new radio (NR) and long term evolution (LTE).

Abstract: A communication method includes a session management network element that establishes a first connection of a user equipment using a first non-3rd Generation Partnership Project (3GPP) access gateway, receives a request message, where the request message is used to request to establish a second connection of the user equipment using a second non-3GPP access gateway, determines, based on the request message, to switch from the first connection to the second connection- and sends, to an access management network element, session management information and access gateway information corresponding to the session management information, to implement switching of a traffic flow between non-3GPP access gateways.

Abstract: A policy control method, a device, and a system, the method including receiving, by a session management network element, from a policy control network element, LAN traffic steering information corresponding to a first application, selecting one or more user plane network elements based on the LAN traffic steering information, determining policy rules corresponding to each user play network element of the user plane network elements, the policy rules being associated with steering data of the first application sent by an upstream network element, where the policy rules are further associated with sending data processed by the local application server for the first application in the target LAN to a downstream network element, and sending, by the session management network element, the corresponding policy rules to each user plane network element of the one or more user plane network elements.

Abstract: A method for determining a network quality of service (QoS) flow, a network element, and a system include receiving, by a session management function network element, a policy and charging control (PCC) rule from a policy control function network element, where the PCC rule includes QoS parameters, the QoS parameters include standardized QoS parameter indication information and a non-standardized QoS parameter, and the non-standardized QoS parameter includes at least one attribute comprised in a standardized QoS parameter corresponding to the standardized QoS parameter indication information and a corresponding value of the at least one attribute, and determining, by the session management function network element based on the standardized QoS parameter indication information and the non-standardized QoS parameter, a QoS flow corresponding to the PCC rule.

Abstract: An augmented reality communication method, apparatus, and system are provided. An auxiliary data channel is established between a terminal device and an AR media processing network element, and a target object is provided to the terminal device through the auxiliary data channel, to augment a media stream of AR communication between a first terminal device and a second terminal device, so as to integrate AR into voice and video calls. A third-party server may provide a material of the target object for the AR communication between the terminal devices, for example, a virtual object.

Abstract: A traffic flow processing method, and apparatus. A terminal device receives first policy information from a session management network element, wherein the first policy information includes a first processing method for an uplink traffic flow. In response to the terminal device meeting a first condition, a second processing method for the uplink traffic flow or a downlink traffic flow is determined. First notification information is sent to a user plane network element, wherein the first notification information is for notifying the user plane network element to determine a third processing method for the downlink traffic flow. After meeting the first condition, the terminal device sends the first notification information to the user plane network element, to assist the user plane network element in determining whether to update a steering mode of a corresponding traffic flow.

Abstract: In a packet loss rate detection method, a session management network element determines that link status detection needs to be performed on a link on which a service flow is located; and the session management network element sends a link status detection indication to a first device and/or a second device, where the link status detection indication is for enabling a link status detection function, and the link status detection function includes a packet loss rate detection function.

Abstract: A communication method and apparatus are provided. The method includes: A session management network element receives first information from user equipment, where the first information indicates a target IMS network to which the user equipment requests to connect, the target IMS network is one of a plurality of IMS networks, and the target IMS network is provided by a target service provider; the session management network element determines first call information based on the first information, where the first call information indicates a target proxy call network element, and the first call information is for establishing a connection between the user equipment and the target IMS network; and the session management network element sends the first call information to the user equipment.

Abstract: A communication method, an apparatus, and a system in which a first session management function entity determines, based on information of a terminal group, user plane function entities accessed by terminals in a terminal group, and the first session management function entity determines a target user plane function entity based on the user plane function entities, where the target user plane function entity is used to perform communication between terminals in the terminal group. According to the method, the terminals in the terminal group are redirected to a same user plane function entity, namely, the target user plane function entity, so that communication between the terminals in the terminal group is locally implemented in the target user plane function entity. This shortens a communication path, and reduces a communication latency.

Abstract: A method, an apparatus, and a system for processing registration backup data are provided. The method includes: a Serving Call Session Control Function (S-CSCF) receives a request from a User Equipment (UE) and judges whether the request carries multi-registration information so as to decide whether to add multi-registration indication information into a Server Assignment Request (SAR) message sent to a Home Subscriber Server (HSS), which then performs operations according to whether the SAR message carries the multi-registration indication information. According to the application, unnecessary signaling interactions and unnecessary data processing between the HSS and the S-CSCF can be avoided, thereby reducing the signaling load, and saving system resources.

Abstract: A method, a related apparatus, and a system for recovering a called service of a terminal are provided. The method includes: when a called request of a user terminal is received, querying an initial proxy-call session control function (P-CSCF) entity with which the user terminal currently registers; if it is detected that the initial P-CSCF is faulty, selecting an available P-CSCF and sending, to the available P-CSCF, a notification message that carries a redundancy identifier, where the redundancy identifier is used to instruct the available P-CSCF to trigger the user terminal to re-register with the P-CSCF; and when a registration complete message sent by the P-CSCF with which the user terminal re-registers is received, delivering the called request to the re-registered P-CSCF to bear a called service of the user terminal.

Abstract: A communication method, an apparatus, and a system in which a first session management function entity based on information of a terminal group determines user plane function entities accessed by terminals in a terminal group, and the first session management function entity determines a target user plane function entity based on the user plane function entities, where the target user plane function entity is used to perform communication between terminals in the terminal group. According to the method, the terminals in the terminal group are redirected to a same user plane function entity, namely, the target user plane function entity, so that communication between the terminals in the terminal group is locally implemented in the target user plane function entity. This shortens a communication path, and reduces a communication latency.

Abstract: A method for determining a policy control network element, in which a mobility management network element obtains first indication information, where the first indication information indicates to select a same policy control network element as a policy control network element for access and mobility management and a policy control network element for session management; the mobility management network element receives a session establishment request from a terminal for establishing a first session; and the mobility management network element sends second indication information and information about a first policy control network element to a session management network element based on the first indication information, where the second indication information indicates to select a same policy control network element as a policy control network element used for access and mobility management and a policy control network element used for session management of the first session.

Abstract: This application provides a communication method, apparatus, and system for a voice service. The method includes: A session management network element determines that a terminal device is to be handed over from a first network to a second network. The session management network element waits until a first moment to send a request message to a mobility management network element in the second network, where the request message is used to request to set up a first bearer for a voice service of the terminal device.

Abstract: In a location change reporting method, a session management function entity receives from a mobility management entity information including location change information of user equipment (UE) in a first presence reporting area (PRA), an identity of the first PRA, and an identity of a PRA set that includes the first PRA. The session management function entity identifies, based on the identity of the PRA set and locally stored PRA subscription information, a subscription entity that subscribes to location change events of the UE in the PRA set, and sends the identity of the first PRA and the location change information of the UE in the first PRA to the subscription entity.

Abstract: A policy control method includes receiving, by a policy control network element, an update request message carrying information about a first mobility management network element from the first mobility management network element, updating, by the policy control network element according to the update request message, information about a second mobility management network element in information of a policy association corresponding to a terminal that is stored in the policy control network element to information about the first mobility management network element. The policy control network updates the information about the second mobility management network element in the information of the policy association to the information about the first mobility management network element instead of deleting the policy association and re-establishing a policy association with the first mobility management network element.

Abstract: A method, apparatus, and system for disaster recovery of an Internet Protocol (IP) Multimedia Subsystem (IMS), where the method includes: triggering a redundant Call Session Control Function (CSCF); obtaining, by the redundant CSCF, user backup data of registered IMS Private User Identities (IMPIs) that are associated with IMPUs and user service configuration data of IMS Public User Identities (IMPUs) in an IMS subscription from a network storage entity of a user; and recovering, by the redundant CSCF, a corresponding service according to the obtained user backup data of the registered IMPIs and user service configuration data of the IMPUs in the IMS subscription. Hence, the one-IMPU multi-IMPI, one-IMPI multi-IMPU, or multi-IMPI multi-IMPU service can be recovered, and this enables the user to have better service continuity experiences.

Abstract: The present disclosure provides a method which includes: receiving a message, where the message carries a parameter indicating a validity period of a short message sent to a user or indication information indicating whether a record needs to be added to MWD of a user when a short message cannot be transmitted or fails to be transmitted; determining that the short message cannot be transmitted or the short message fails to be transmitted, and a value of the parameter is 0 or the indication information indicates that the record does not need to be added to the MWD of the user when the short message cannot be transmitted or fails to be transmitted; and skipping adding the record to the MWD of the user, where the record includes an identifier of a service center for short message service serving the user. According to the method, additional signaling interaction is reduced.