Abstract: A local network accessing method and apparatus are provided. The local network accessing method comprises sending a trigger message to a terminal, the trigger message is for triggering the terminal to establish a session, receiving a first message from the terminal, the first message requesting to establish a first session, and the first session is for the terminal to access a target local network, determining a target network access identifier based on the first message, the target network access identifier indicating the target local network, determining a first session management function network element based on the target network access identifier, and sending the target network access identifier to the first session management function network element, the target network access identifier is for the first session management function network element to determine a target user plane function network element.

Abstract: In a re-allocation process of a first user plane function network element to a second user plane function network element, a session management function network element sends a respective session modification request to each anchor user plane function network element of a plurality of anchor user plane function network elements, where each session modification request includes information about the second user plane function network element; and indicates to only a first anchor user plane function network element in the plurality of anchor user plane function network elements to send an end marker; or sends the end marker to only the first anchor user plane function network element.

Abstract: A transmission method and apparatus related to the field of communications technologies and include obtaining, by a session management network element, transport network capability list information, where the transport network capability list information indicates whether a transport network supports high-reliability transmission, and the transport network is a network between an access device and a user plane network element, and managing, by the session management network element, a user plane connection, of a terminal, between the access device and the user plane network element based on the transport network capability list information, where the user plane connection is usable for transmitting a service flow packet of the terminal.

Abstract: This application provides a method and an apparatus for determining an air interface latency and relates to the field of communications technologies. In the method, an access network device obtains an air interface latency of a downlink data packet and schedules the downlink data packet based on the air interface latency of the downlink data packet. The air interface latency of the downlink data packet is calculated based on a round-trip latency, and the round-trip latency is a latency from when a terminal sends an uplink data packet to when the terminal receives the downlink data packet corresponding to the uplink data packet. In the method, the access network device may schedule the downlink data packet based on the air interface latency of the downlink data packet, so as to precisely control a latency in uplink and downlink data transmission.

Abstract: A cell selection method includes obtaining measurement results of N cells. The cell selection method also includes obtaining cell selection assistance information. The cell selection assistance information includes identifiers of L slices corresponding to M sessions of a terminal device and slice capability information of the N cells, the slice capability information of the N cells includes identifiers of slices supported by the N cells, and M, L, and N are positive integers. The cell selection method further includes performing cell selection or cell reselection based on the measurement results of the N cells and the cell selection assistance information.

Abstract: Embodiments of this disclosure provide a communication method and apparatus, to reduce a waiting delay during transmission of retransmitted data and out-of-order data. In this method, a user plane function network element may receive first data and second data, determines, based on first information, that the second data is retransmitted data of the first data, and sends indication information to an access network network element. The indication information herein may indicate that the second data is the retransmitted data, or indicate a sending priority of the second data. Based on this solution, the access network network element may send the first data and the second data based on the indication information, and may preferentially send the retransmitted data to reduce the waiting delay during data transmission.

Abstract: A packet transmission method, including receiving, by a session management function network element, first access network tunnel information and second access network tunnel information that correspond to a first service, and sending a downlink forwarding rule to a user plane function network element, where the downlink forwarding rule includes the first access network tunnel information and the second access network tunnel information, and the downlink forwarding rule indicates the user plane function network element to replicate a received downlink packet of the first service, and send downlink packets of the first service through two paths respectively corresponding to the first access network tunnel information and the second access network tunnel information.

Abstract: A method includes: receiving, by a session management function (SMF) network element, identification information from an access and mobility management function (AMF) network element; obtaining, by the SMF network element, information about a plurality of anchor user plane function (UPF) network elements of a session based on the identification information, wherein each of the plurality of anchor UPF network elements is used as an Internet protocol (IP) anchor of a user equipment in the session; and sending, by the SMF network element, the information to a branching point, wherein the branching point is a UPF network element managed by the SMF network element and the branching point is capable of diverting traffic.

Abstract: A service packet transmission method and apparatus, the method including receiving, by the source mobile edge computing network element, after a source mobile edge computing network element receives a second uplink service packet, a first uplink service packet sent by a source user plane network element and that is from a target user plane network element, where the second uplink service packet is the last uplink service packet sent by the source mobile edge computing network element to a source application server, sending, by the source mobile edge computing network element, the first uplink service packet to a target mobile edge computing network element, and sending, by the source mobile edge computing network element, first indication information to the target mobile edge computing network element, the first indication information indicating that the sending of the first uplink service packet by the source mobile edge computing network element ends.

Abstract: An information determining method and a related device. In the method, a first network element receives first information from a first terminal device, where the first information includes first indication information. The first network element determines, based on the first indication information, a first access network device connected to the first access network device, determines second information based on historical statistical information of a bandwidth between the first access network device and the first terminal device, and further sends the second information to a second network element, where the second information is useable for determining a first code rate, and the first code rate indicates a code rate of media data of first media received by the first terminal device. This improves accuracy and real-time performance of code rate adjustment of the media data, and further improve effectiveness of the code rate adjustment.

Abstract: Embodiments of this application provide example media packet transmission methods, apparatuses, and systems, and relate to the field of communication technologies. One example method includes receiving, by a user plane network element, a media packet from an application server. The user plane network element determines association information corresponding to the media packet, where the association information is information associated with a client operation corresponding to the media packet. The user plane network element then sends the media packet to an access network element via a quality of service (QoS) flow corresponding to the association information.

Abstract: A packet transmission method, including receiving, by a session management function network element, first access network tunnel information and second access network tunnel information that correspond to a first service, and sending a downlink forwarding rule to a user plane function network element, where the downlink forwarding rule includes the first access network tunnel information and the second access network tunnel information, and the downlink forwarding rule indicates the user plane function network element to replicate a received downlink packet of the first service, and send downlink packets of the first service through two paths respectively corresponding to the first access network tunnel information and the second access network tunnel information.

Abstract: This application provides a network connection configuration method and an apparatus. The method is as follows: After a terminal device obtains network configuration information of an application in the terminal device, the terminal device sends the network configuration information to a core network control plane network element, so that the core network control plane network element may determine a network connection that is of the application and is between the terminal device and the data network and that meets the network configuration information.

Abstract: Various embodiments provide a packet transmission method and an apparatus. In those embodiments, a first device supports a first protocol layer, and replicates a packet at the first protocol layer. A second device supports a second protocol layer, and deduplicates the packet at the second protocol layer. When receiving a first packet, a first access device converts a sequence number of the first protocol layer in the first packet into a sequence number of the second protocol layer, and then sends, to the second device, a second packet that carries the sequence number of the second protocol layer and a data packet of the first packet. For example, if the first access network device receives two packets having same data packets, the first access network device separately coverts sequence numbers in the two packets without performing operations of first deduplicating and then replicating the packet.

Abstract: Embodiments of this application provide a media packet transmission method, an apparatus, and a system that relate to the field of communication technologies. In an example method, a transmit end network element obtains a correspondence between an encoding type and a quality of service (QoS) flow. The transmit end network element is a user plane network element or a terminal. The QoS flow is used to transmit a media packet whose encoding type is the encoding type corresponding to the QoS flow. The transmit end network element identifies an encoding type of a received media packet, and sends, based on the correspondence through a QoS flow corresponding to the encoding type of the media packet, the media packet carrying information associated with the encoding type to an access network element.

Abstract: Example network-based adaptive streaming media parameter adjustment methods and apparatuses are disclosed. One example method includes receiving, by an access network device, media QoS information from a session management network element, where the media QoS information includes at least two bit rate indicators and QoS requirement information corresponding to each of the bit rate indicators. The access network device determines, based on a current network condition and the media QoS information, a target bit rate indicator from the at least two bit rate indicators. The target bit rate indicator is sent to a terminal or a video server, where the current network condition meets a network requirement for transmitting streaming media data at a bit rate indicated by the target bit rate indicator.

Abstract: A method for processing a time synchronization packet is provided. In an embodiment a terminal device receives a time synchronization packet of a first clock source from an external device; receives first indication information from a network device, where the first indication information instructs the terminal device to enter a time synchronization activated state of the first clock source, or the first indication information instructs the terminal device to enter a time synchronization deactivated state of the first clock source; and processes the time synchronization packet of the first clock source based on the first indication information. When a clock source is activated and deactivated, the terminal device processes a time synchronization packet of the clock source in different manners, and signaling indicates whether the clock source is activated or deactivated.

Abstract: This disclosure provides a time synchronization packet processing method and apparatus. The method includes: A terminal device receives first indication information, where the first indication information indicates the terminal device to enter an activation state of time synchronization for a first clock source, or the first indication information indicates the terminal device to enter a deactivation state of time synchronization; and processes a time synchronization packet of the first clock source based on the first indication information.

Abstract: A multicast communication method and a communication apparatus provide for transmission of data of a multicast service using a PDU session established by a terminal device to improve network element utilization. An AF network element sends first multicast service indication information to a session management network element indicating a first multicast service. The session management network element sends, based on the first multicast service indication information, multicast service information to an access network device that serves a terminal device. The access network device establishes an association relationship between the terminal device and the first multicast service based on the multicast service information, so that the access network device can send, when receiving data of the first multicast service, the data of the first multicast service to the terminal device using a PDU session.

Abstract: A method includes: receiving, by a policy control function network element, request information from an application function network element, where the request information includes a continuity requirement of an APP; and sending, by the policy control function network element, first policy information to user equipment, where the first policy information includes an SSC mode of the APP, the first policy information is associated with the continuity requirement of the APP, and the first policy information is for determining whether to reuse or newly establish a session.