WO2023029590A1

WO2023029590A1 - Multicast/broadcast session management method and communication apparatus

Info

Publication number: WO2023029590A1
Application number: PCT/CN2022/093110
Authority: WO
Inventors: 贾建鑫; 吴问付; 宗在峰; 朱奋勤
Original assignee: 华为技术有限公司
Priority date: 2021-08-31
Filing date: 2022-05-16
Publication date: 2023-03-09
Also published as: CN115734170A

Abstract

Provided in the present application are a multicast/broadcast session management method and a communication apparatus. The method comprises: a session management function network element sending first information to an intermediate session management function network element, wherein the first information comprises information of a first multicast/broadcast service; and the session management function network element receiving second information from the intermediate session management function network element, wherein the second information is used for indicating that a first tunnel for transmitting data of the first multicast/broadcast service between an intermediate user plane function network element and a multicast/broadcast user plane function network element has been established. By means of the technical solution, a session management function network element can learn that a first tunnel has been established, thereby facilitating the optimization of a transmission path of data of a first multicast/broadcast service by using the first tunnel, reducing the transmission delay of the data of the multicast/broadcast service, and saving on network transmission resources.

Description

A multicast/broadcast session management method and communication device

Cross References to Related Applications

This application claims the priority of the Chinese patent application submitted to the State Intellectual Property Office of China on August 31, 2021, with the application number 202111016643.1 and the application name "A Multicast/Broadcast Session Management Method and Communication Device", the entire content of which Incorporated in this application by reference.

technical field

The present application relates to the technical field of wireless communication, and in particular to a multicast/broadcast session management method and a communication device.

Background technique

With the development of mobile Internet, mobile high-definition video services are showing a blowout trend. Users are gradually changing from watching popular programs through fixed TV to watching popular programs through mobile terminals and mobile Internet. Therefore, the impact of video services on mobile networks is becoming more and more intense. If the video service can be optimized through air interface multicast Transmission will greatly reduce the impact of video traffic on mobile networks.

At present, the 5th generation (the 5th generation, 5G) mobile communication network can support multicast/broadcast service (multicast broadcast service, MBS). However, due to the limited service area of the session management function (session management function, SMF) and the user plane function (UPF), when the terminal device moves, the insertion of the intermediate session management function (I-SMF) and Intermediate user plane function (intermediate user plane function, I-UPF), and the multicast/broadcast service data of the terminal device is transmitted through the protocol data unit (protocol data unit, PDU) session of the terminal device, the multicast/broadcast service data There may be detours in the transmission path, which will cause waste of network resources and increase data transmission delay.

Contents of the invention

The present application provides a multicast/broadcast session management method and communication device, which are used to optimize the transmission path of multicast/broadcast service data, thereby saving network resources and reducing the transmission delay of multicast/broadcast service data.

In the first aspect, the embodiment of the present application provides a multicast/broadcast session management method, which may be executed by a session management function network element, or may be executed by a component (such as a chip or a circuit) configured on the session management function network element.

The method includes: the session management function network element sends the first information to the intermediate session management function network element, the first information includes the information of the first multicast/broadcast service, and the session management function network element is used to control the connection between the terminal equipment and the first The PDU session anchor point of the protocol data unit PDU session associated with the multicast/broadcast service; the session management function network element receives the second information from the intermediate session management function network element, the second information is used to indicate that the first tunnel has been established, the The first tunnel is used to transmit the data of the first multicast/broadcast service between the intermediate user plane functional network element and the multicast/broadcast user plane functional network element, and the intermediate session management functional network element is used to control the intermediate user plane functional network Yuan.

In the above technical solution, the session management function network element sends the first information to the intermediate session management function network element. After a tunnel is established, the second information is sent to the session management function network element, so that the session management function network element knows that the first tunnel has been established, so as to facilitate the use of the first tunnel to optimize the data transmission path of the first multicast/broadcast service, Reduce the transmission delay of multicast/broadcast service data and save network transmission resources.

In a possible design of the first aspect, the first tunnel is a direct tunnel between the intermediate user plane functional network element and the multicast/broadcast user plane functional network element.

In a possible design of the first aspect, the first information includes first indication information, and the first indication information is used to trigger the intermediate session management function network element to establish the first tunnel, or the first indication information is used to Query whether the first tunnel has been established from the network element with the intermediate session management function.

In a possible design of the first aspect, the second information includes information about the first multicast/broadcast service.

In a possible design of the first aspect, the information of the first multicast/broadcast service includes one or more of the following information: identification information of the first multicast/broadcast service, The identification information of the regional session, the multicast/broadcast QoS information of the first multicast/broadcast service, or the unicast QoS information corresponding to the multicast/broadcast QoS information of the first multicast broadcast service.

In a possible design of the first aspect, the method further includes: the session management function network element receives the multicast/broadcast capability information from the intermediate session management function network element, the multicast/broadcast capability information is used to indicate the intermediate session Whether the management function network element supports multicast/broadcast; the session management function network element sends the first information to the intermediate session management function network element, including: the session management function network element sends the intermediate session management function information according to the multicast/broadcast capability information The network element sends the first information.

In the above technical solution, the session management function network element can send the first information to the intermediate session management function network element after confirming that the intermediate session management function network element supports multicast/broadcast according to the multicast/broadcast capability information of the intermediate session management function network element , so that the data transmission path of the first multicast/broadcast service can be optimized subsequently by establishing the first tunnel.

In a possible design of the first aspect, the method further includes: the session management function network element sends a first message to the PDU session anchor according to the second information, and the first message is used to trigger the release of the PDU session anchor. resources for transmitting data of the first multicast/broadcast service.

In a second aspect, the embodiment of the present application provides a multicast/broadcast session management method, which can be performed by an intermediate session management function network element, or can be configured by a component (such as a chip or a circuit) configured on an intermediate session management function network element implement.

The method includes: the intermediate session management function network element receives the first information from the session management function network element, the first information includes the information of the first multicast/broadcast service, and the session management function network element is used to control the connection between the terminal equipment and the first The PDU session anchor point of the protocol data unit PDU session associated with the multicast/broadcast service; the intermediate session management function network element sends the second information to the session management function network element according to the first information, and the second information is used to indicate the first tunnel Already established, the first tunnel is used to transmit the data of the first multicast/broadcast service between the intermediate user plane functional network element and the multicast/broadcast user plane functional network element, and the intermediate session management functional network element is used to control the intermediate User plane functional network element.

In a possible design of the second aspect, the first tunnel is a direct tunnel between the intermediate user plane functional network element and the multicast/broadcast user plane functional network element.

In a possible design of the second aspect, the first information includes first indication information; the method further includes: the intermediate session management function network element establishes the first tunnel according to the first indication information, or queries the first tunnel whether it has been established.

In a possible design of the second aspect, the second information includes information about the first multicast/broadcast service.

In a possible design of the second aspect, the information of the first multicast/broadcast service includes one or more of the following information: identification information of the first multicast/broadcast service, first multicast/broadcast service The identification of the regional session, the multicast/broadcast quality of service QoS information of the first multicast/broadcast service, or the unicast QoS information corresponding to the multicast broadcast QoS information of the first multicast/broadcast service.

In a possible design of the second aspect, the method further includes: the intermediate session management function network element sends the multicast/broadcast capability information of the intermediate session management function network element to the session management function network element, the multicast/broadcast capability The information is used to indicate whether the intermediate session management function network element supports multicast/broadcast.

In a possible design of the second aspect, the method further includes: the intermediate session management functional network element sending a second message to the intermediate user plane functional network element, where the second message is used to trigger the intermediate user plane functional network element to transmit Data configuration resources of the first multicast/broadcast service.

For the beneficial effects of the method in the second aspect and any possible design thereof, please refer to the corresponding description of the first aspect, and details will not be repeated here.

In the third aspect, the embodiment of the present application provides a communication device, which can have the function of realizing the session management function network element or the intermediate session management function network element in the above aspects, and the communication device can be a network device or a Chips included in networking equipment.

The above-mentioned functions of the communication device may be realized by hardware, or may be realized by executing corresponding software by hardware, and the hardware or software includes one or more modules or units or means corresponding to the above-mentioned functions.

In a possible design, the structure of the communication device includes a processing module and a transceiver module, wherein the processing module is configured to support the communication device to perform the corresponding functions of the session management function network element in the above aspects, or to perform the above various aspects. The corresponding function of the intermediate session management function network element in the aspect. The transceiver module is used to support communication between the communication device and other communication devices, for example, when the communication device is a network element with a session management function, it can send the first information to an intermediate network element with a session management function. The communication device may also include a storage module, which is coupled to the processing module and stores necessary program instructions and data of the communication device. As an example, the processing module may be a processor, the communication module may be a transceiver, and the storage module may be a memory, and the memory may be integrated with the processor or configured separately from the processor.

In another possible design, the structure of the communication device includes a processor, and may also include a memory. The processor is coupled with the memory, and is operable to execute computer program instructions stored in the memory, so as to cause the communication device to perform the methods in the above aspects. Optionally, the communication device further includes a communication interface, and the processor is coupled to the communication interface. When the communication device is a network device, the communication interface may be a transceiver or an input/output interface; when the communication device is a chip included in the network device, the communication interface may be an input/output interface of the chip. Optionally, the transceiver may be a transceiver circuit, and the input/output interface may be an input/output circuit.

In a fourth aspect, an embodiment of the present application provides a chip system, including: a processor, the processor is coupled to a memory, and the memory is used to store programs or instructions, and when the programs or instructions are executed by the processor , so that the chip system implements the methods in the above aspects.

Optionally, the chip system further includes an interface circuit, which is used for exchanging code instructions to the processor.

Optionally, there may be one or more processors in the chip system, and the processors may be implemented by hardware or by software. When implemented in hardware, the processor may be a logic circuit, an integrated circuit, or the like. When implemented by software, the processor may be a general-purpose processor implemented by reading software codes stored in a memory.

Optionally, there may be one or more memories in the chip system. The memory can be integrated with the processor, or can be set separately from the processor. Exemplarily, the memory may be a non-transitory processor, such as a read-only memory ROM, which may be integrated with the processor on the same chip, or may be respectively disposed on different chips.

In the fifth aspect, the embodiment of the present application provides a computer-readable storage medium on which a computer program or instruction is stored. When the computer program or instruction is executed, the communication device executes any one of the above-mentioned aspects or aspects. possible design approach.

In a sixth aspect, the embodiment of the present application provides a computer program product, which, when the communication device executes the computer program product, causes the communication device to execute the method in any possible design of the above aspects or aspects.

In a seventh aspect, the embodiment of the present application provides a communication system, where the communication system includes a session management function network element and an intermediate session management function network element. Optionally, the communication system may further include one or more of an anchor user plane functional network element, an intermediate user plane functional network element, a multicast/broadcast session management functional network element, and a multicast/broadcast user plane functional network element network element.

Description of drawings

FIG. 1 is a schematic diagram of a network architecture of a communication system applicable to an embodiment of the present application;

FIG. 2 is a schematic diagram of a network architecture of a communication system supporting multicast/broadcast services applicable to an embodiment of the present application;

FIG. 3 is a schematic diagram of two data transmission modes of multicast/broadcast services in a 5G network;

FIG. 4 is a schematic flowchart of a multicast/broadcast session management method provided by an embodiment of the present application;

5 is a schematic diagram of the effect of path optimization for the first multicast/broadcast service in the scenario of inserting an I-SMF in the embodiment of the present application;

FIG. 6 is a possible implementation of a multicast/broadcast session management method provided in the embodiment of the present application in the scenario of replacing the I-SMF;

7 is a schematic diagram of the effect of path optimization for the first multicast/broadcast service in the scenario of replacing the I-SMF in the embodiment of the present application;

Fig. 8 is another possible implementation of a multicast/broadcast session management method provided in the embodiment of this application in the scenario of replacing I-SMF;

FIG. 9 is a schematic flow diagram of Example 1 in the embodiment of the present application;

FIG. 10 is a schematic flow diagram of Example 2 in the embodiment of the present application;

FIG. 11 is a schematic flow diagram of Example 3 in the embodiment of the present application;

FIG. 12 is a schematic flow diagram of Example 4 in the embodiment of the present application;

FIG. 13 and FIG. 14 are schematic structural diagrams of a communication device provided by an embodiment of the present application.

Detailed ways

In order to make the purpose, technical solutions, and advantages of the embodiments of the present application clearer, the embodiments of the present application will be further described in detail below in conjunction with the accompanying drawings.

Please refer to FIG. 1 , which shows a network architecture of a communication system to which this embodiment of the present application applies. As shown in Figure 1, the communication system includes three parts: terminal equipment, data network (data network, DN) and operator network.

Among them, the operator network may include but not limited to one or more of the following network elements or functional entities: access and mobility management function (access and mobility management function, AMF) network element, session management function (session management function, SMF) network element, user plane function (UPF) network element, unified data management (unified data management, UDM) network element, policy control function (policy control function, PCF) network element, authentication server function (authentication server function (AUSF) network element, network slice selection function (network slice selection function, NSSF) network element, application function (application function, AF) network element and radio access network (radio access network, RAN) equipment. Optionally, the operator network may also include some network elements not shown, such as a network function storage function (network function repository function, NRF) network element, a unified data repository (unified data repository, UDR) network element, or a network Open function (network exposure function, NEF) network element, etc.

In a specific implementation, a terminal device is a device for implementing a wireless communication function, and may also be called a terminal, user equipment (user equipment, UE), mobile station, mobile terminal, and the like. In this application, the terminal equipment may be user equipment (user equipment, UE), access terminal, terminal unit, terminal station, mobile station, Mobile station, remote station, remote terminal, mobile equipment, wireless communication equipment, terminal agent or terminal device, etc. An access terminal may be a cellular phone, a cordless phone, a session initiation protocol (SIP) phone, a wireless local loop (WLL) station, a personal digital assistant (PDA), a Functional handheld devices, computing devices or other processing devices connected to wireless modems, vehicle-mounted devices or wearable devices, virtual reality (virtual reality, VR) terminal devices, augmented reality (augmented reality, AR) terminal devices, industrial control (industrial Wireless terminals in control, wireless terminals in self driving, wireless terminals in remote medical, wireless terminals in smart grid, wireless terminals in transportation safety Terminals, wireless terminals in smart cities, wireless terminals in smart homes, etc. This application does not limit the specific technology and specific equipment form adopted by the terminal equipment. Terminal equipment may be mobile or fixed, and it is not limited.

The above-mentioned terminal device can establish a connection with the operator network through an interface provided by the operator network (such as an N1 interface, etc.), and use services such as data and/or voice provided by the operator network. The terminal device can also access the DN through the operator's network, and use the operator's service deployed on the DN and/or the service provided by a third party. Wherein, the above-mentioned third party may be a service provider other than the operator's network and the terminal device, and may provide other data and/or voice services for the terminal device. Among them, the specific form of expression of the above-mentioned third party can be determined according to the actual application scenario, and is not limited here.

The radio access network is a sub-network of the operator's network and an implementation system between service nodes and terminal equipment in the operator's network. To access the operator's network, the terminal equipment first passes through the wireless access network, and then can be connected to the service node of the operator's network through the wireless access network.

An access network device is a device that provides a wireless communication function for a terminal device, and is also called a RAN device (node). In this application, the access network device may be a next-generation base station (g nodeB, gNB), an evolved node B (evolved node B, eNB), a radio network controller (radio network controller, RNC), or a node B in a 5G network. (node B, NB), base station controller (base station controller, BSC), base transceiver station (base transceiver station, BTS), home base station (for example, home evolved nodeB, or home node B, HNB), baseband unit (baseBand unit, BBU), transmission point (transmitting and receiving point, TRP), transmission point (transmitting point, TP), mobile switching center, etc. The access network device may also be a module or unit that completes some functions of the base station, such as a centralized unit (central unit, CU) or a distributed unit (distributed unit, DU). This application does not limit the specific technology and specific equipment form adopted by the RAN equipment.

The AMF network element is responsible for access and mobility management functions, which can receive non-access stratum (non-access stratum, NAS) signaling of terminal equipment (for example, including mobility management (MM) signaling and session management (session management, SM) signaling) and related signaling of access network equipment (for example, including N2 signaling at the granularity of the base station interacting with AMF network elements), complete the user registration process and SM signaling forwarding and mobility manage.

The SMF network element is responsible for the session management function, and completes the establishment, release, update and other processes related to the protocol data unit (protocol data unit, PDU) session.

The UPF network element is responsible for user plane business processing, such as data packet routing and transmission, packet detection, service usage reporting, quality of service (QoS) processing, lawful interception, upstream packet detection, and downlink data packet storage, etc.

PDU session anchor UPF (PDU session anchor UPF, PSA UPF), also known as PDU session anchor, as the anchor point connected to the PDU session, is responsible for the filtering, forwarding, rate control and billing of the user plane data of the terminal device. .

The intermediate UPF (intermediate, I-UPF) network element, also known as the forwarding UPF network element, can be used to forward user plane data between the access network device and the PSA UPF or between the I-UPF and the PSA-UPF.

The PCF network element is responsible for user policy management, including both mobility-related policies and PDU session-related policies, such as quality of service (QoS) policies and charging policies.

The UDM network element is responsible for managing subscription data, user access authorization and other functions.

The UDR network element is responsible for the access function of contract data, policy data, application data and other types of data.

The AUSF network element is responsible for authenticating and authorizing the access of terminal equipment.

The AF network element is responsible for transmitting the requirements from the application side to the network side, such as QoS requirements or user status event subscription. AF can be a third-party functional entity, or an application service deployed by an operator. The AF network element may also be called an application server, or a third-party device, and the like.

The data network is used to provide users with business services, such as operator's business, Internet access business and third-party business. The data network can be a private network, such as a local area network, or an external network not controlled by the operator, such as the Internet (Internet), or a proprietary network jointly deployed by the operator, such as the configured IP multimedia network subsystem (IP multimedia core network subsystem, IMS) service.

As shown in FIG. 1 , a terminal device can access the communication system through an access network device. The terminal device can communicate with the AMF network element through the next generation network (Next generation, NG) 1 interface (N1 for short), the access network device can communicate with the AMF network element through the N2 interface (N2 for short), and the access network device can communicate with the AMF network element through the N3 interface ( N3 for short) communicates with the UPF network element, the AMF network element communicates with the SMF network element through the N11 interface (N11 for short), the AMF network element communicates with the UDM network element through the N8 interface (N8 for short), and the AMF network element communicates with the UDM network element through the N12 interface (N12 for short). ) communicates with the AUSF network element, the AMF network element communicates with the PCF network element through the N15 interface (N15 for short), the SMF network element communicates with the PCF network element through the N7 interface (N7 for short), and the SMF network element communicates with the PCF network element through the N4 interface (N4 for short). The UPF network element communicates, the NEF network element communicates with the SMF network element through the N29 interface (N29 for short), and the UPF network element accesses the data network (data network, DN) through the N6 interface (N6 for short).

It should be noted that the shape and quantity of the network elements shown in FIG. 1 are for example only, and do not limit the present application. The network architecture involved in FIG. 1 may also include other network elements, which is not specifically limited. In addition, the name of each network element and the interface between each network element in FIG. 1 is just an example. In a specific implementation, the name of each network element and the interface between each network element may be other, which is not specifically limited in this embodiment of the present application. .

Please refer to FIG. 2 , which shows a network architecture supporting multicast/broadcast services provided by this application. The network architecture is extended on the basis of the network architecture shown in Figure 1, adding, for example, multicast broadcast session management function network elements (multicast broadcast session management function, MB-SMF) network elements and multicast broadcast user plane function network elements (multicast broadcast user plane function, MB-UPF) network element or functional entity, used to support multicast/broadcast services.

Among them, the MB-SMF can realize the control plane function of the multicast/broadcast service, and is responsible for the management of the multicast/broadcast service/group/session. From the perspective of the control plane, MB-SMF can be connected with NEF and/or multicast/broadcast service function (multicast/broadcast service function, MBSF), for example, for receiving information related to multicast/broadcast services (for example, multicast /Description information of broadcasting service). In addition, MB-SMF can also be connected with PCF, for example, can extract policy and charging control (policy and charging control, PCC) rules related to multicast/broadcast services. From the user perspective, MB-UPF can be connected to multicast/broadcast service transport function (multicast/broadcast service transport function, MBSTF) and/or AF/AS to receive service data of multicast/broadcast services. It should be noted that MB-SMF and SMF can be deployed together or deployed separately, and MB-UPF and UPF can be deployed together or deployed separately, which is not limited in this application.

It should be noted that the above name of MB-SMF or MB-UPF is an example, and in a 5G network, MB-SMF or MB-UPF may also have other names, which are not limited in this application.

For the convenience of description, in the follow-up of this application, the network element with the session management function is the SMF, and the network element with the user plane function is the UPF as an example for description. That is, the SMF described later in this application can be replaced by a session management function network element, and the UPF can be replaced by a user plane function network element. In addition, in order to adapt to the development of the communication system, the above functional network elements can be replaced by devices with the same or similar functions, without limitation.

The relevant technical features involved in the embodiments of the present application are introduced below.

1. Multicast/Broadcast

Multicast/broadcast refers to multicast (multicast) or broadcast (broadcast), which can be understood as "point to multi-point" (point to multi-point, PTM) communication. At the service level, the multicast/broadcast service means that the data of this service is sent to multiple terminal devices. At the service level of the core network, the multicast/broadcast service refers to the service data of the multicast/broadcast service sent to terminal equipment through a multicast/broadcast session. Between network elements, multicast refers to a multicast tunnel between a source network element and a target network element (that is, the IP address of the target network element is a multicast IP address). For the air interface, the air interface multicast/broadcast mode refers to a piece of service data sent by the access network device, and multiple terminal devices can receive it at the same time and/or on the same frequency. The embodiments of the present application can be applied not only to multicast service transmission, but also to broadcast service transmission.

2. Multicast/broadcast service data transmission mode

In the case that the access network equipment does not support multicast/broadcast, the multicast/broadcast service can be transmitted between the access network equipment and UPF in the form of 5GC individual MBS traffic delivery (5GC individual MBS traffic delivery) The data. When the access network device supports multicast/broadcast, the access network device and UPF can transmit the multicast/broadcast service in the form of 5GC shared MBS traffic delivery (5GC shared MBS traffic delivery) data.

For example, as shown in Figure 3, in the 5G core network shared multicast/broadcast service traffic transmission mode, the data of the multicast/broadcast service directly reaches the RAN through the MB-UPF and the N3mb tunnel between the MB-UPF and the RAN, and the RAN can It is sent to one or more UEs joining the multicast session in a point-to-point (point to point, PTP) or point-to-multipoint (point to multi-point, PTM) manner. In the 5G core network independent multicast/broadcast service traffic transmission mode, the data of the multicast/broadcast service passes through the MB-UPF to the UPF, and then reaches the RAN through the N3 tunnel between the UPF and the RAN (such as the PDU session of the UE), and the RAN Point-to-point sent to UE.

The multicast/broadcast capability information of the access network device can be used to indicate whether the access network device supports multicast/broadcast (that is, to indicate whether the access network device has the processing capability of multicast/broadcast. Supporting multicast/broadcast Access network devices can identify and process information related to multicast/broadcast services, while access network devices that do not support multicast/broadcast functions cannot identify and process information related to multicast/broadcast services.

Access network equipment supporting multicast/broadcast may refer to: the access network equipment supports the transmission of multicast/broadcast service data through the 5G core network shared multicast/broadcast service traffic transmission mode, and supports group Enhancement of signaling plane interaction for broadcast/broadcast services, support for receiving multicast/broadcast service data from core network user plane functional network elements, support for local processing of multicast/broadcast service data, and support for point-to-multipoint transmission over the air interface The data of the multicast/broadcast service and the data of configuring the response terminal to receive the multicast/broadcast service.

The fact that the access network equipment does not support multicast/broadcast can refer to: the access network equipment does not support the transmission of multicast/broadcast service data in the 5G core network shared multicast/broadcast service traffic transmission mode, and only supports separate multicast on the 5G core network The multicast/broadcast service data is transmitted in the traffic transmission mode of the multicast/broadcast service, and the data of the multicast/broadcast service is sent to the terminal device through the associated PDU session of the terminal device joining the multicast/broadcast session.

It should be understood that after the data of the multicast/broadcast service arrives at the access network device (for example, RAN), it passes through the service data adaptation protocol (service data adaptation protocol, SDAP) layer of the access network device, packet data convergence protocol (packet data convergence protocol) Convergence protocol, PDCP) layer, radio link control (radio link control, RLC) layer, media access control (media access control, MAC) layer, physical (physical, PHY) layer processing, sent to each receiving multicast / UE broadcasting traffic data.

3. Association between PDU session and multicast/broadcast service

A terminal device can have multiple PDU sessions, and each PDU session can be associated with one or more multicast/broadcast services, that is, a terminal device can join one or more multicast/broadcast services through one PDU session. It should be noted that the multicast/broadcast service is of service level/granularity, one multicast/broadcast service can correspond to multiple terminal devices, and multiple terminal devices can also join the same multicast/broadcast service at the same time.

The PDU session is associated with the multicast/broadcast service. It can be understood that the session management context of the PDU session is associated with the multicast/broadcast service. For example, the identification information of the multicast/broadcast service can be stored in the PDU session. The method in the management context associates the PDU session with the multicast service; or, it can also be understood that the multicast broadcast session context is associated with the terminal device, for example, by storing the identification information of the terminal device in the multicast/broadcast session context Associate the PDU session with the multicast service in the manner in.

The terminal device joining the multicast/broadcast service through the PDU session may refer to joining the multicast/broadcast service through the user plane of the PDU session (for example, adding signaling through the Internet group management protocol (internet group management protocol, IGMP)), or It may refer to joining the multicast/broadcast service through the control plane of the PDU session (for example, through NAS signaling), which is not limited in this application.

In addition, the terminal device may also actively withdraw from one or more multicast/broadcast services associated with the PDU session. After the terminal device exits a certain multicast/broadcast service associated with the PDU session, it means that the PDU session is also disassociated from the multicast/broadcast service.

It should be noted that the terms "system" and "network" in the embodiments of the present application may be used interchangeably. "Multiple" means two or more, and in view of this, "multiple" can also be understood as "at least two" in the embodiments of the present application. "At least one" can be understood as one or more, such as one, two or more. For example, including at least one means including one, two or more, and does not limit which ones are included. For example, where at least one of A, B, and C is included, then A, B, C, A and B, A and C, B and C, or A and B and C may be included. Similarly, the understanding of descriptions such as "at least one" is similar. "And/or" describes the association relationship of associated objects, indicating that there may be three types of relationships, for example, A and/or B may indicate: A exists alone, A and B exist simultaneously, and B exists independently. In addition, the character "/", unless otherwise specified, generally indicates that the associated objects before and after are in an "or" relationship.

Unless otherwise specified, ordinal numerals such as "first" and "second" mentioned in the embodiments of this application are used to distinguish multiple objects, and are not used to limit the order, timing, priority or importance of multiple objects. Moreover, the descriptions of "first" and "second" do not limit that the objects must be different.

Please refer to Figure 4, which is a multicast/broadcast session management method provided by the embodiment of the present application, the method includes:

Step 401, SMF sends first information to I-SMF.

Correspondingly, the I-SMF receives the first information from the SMF.

Wherein, the SMF can be used to control the PSA UPF of the PDU session associated with the terminal device and the first multicast/broadcast service.

It should be noted that the embodiments of the present application are applicable to a scenario where the terminal device moves. Specifically, as the terminal device moves, when the terminal device moves out of the service area of the SMF, that is, the target access network device to which the terminal device moves cannot be covered by the service areas of all UPFs controlled by the SMF, that is, the target access network device When the device cannot connect to any UPF among all the UPFs controlled by the SMF, it can insert the I-SMF, which is responsible for forwarding the control plane signaling between the target access network device and the SMF. The I-SMF can be further inserted into the I-UPF, which is responsible for forwarding user plane data between the target access network device and the PSA UPF or MB-UPF. In this application, the service area of a UPF refers to the list of cells that the UPF can connect to (i.e. cell list) and/or the list of tracking area identifiers (i.e. TAI list), and the service area of an SMF refers to the list of cells controlled by the SMF. The union of the service areas of all UPFs.

SMF can be used to control the PSA UPF, which is the anchor UPF of the PDU session associated with the terminal device. For example, after the terminal device establishes a PDU session through the source access network device, the source access network device and the PSA UPF The connected UPF means that the source access network device is within the service area of the PSA UPF, and the source access network device can be connected to the PSA UPF. In this application, the connection between the source access network device and the PSA UPF can be understood as that an N3 tunnel or a general packet radio service tunneling protocol-user plane (general packet radio service tunneling protocol-user plane, GTP-U) can be established between the two Tunnel for data transmission. The I-SMF is used to control the I-UPF. For example, the I-UPF is the UPF connected to the target access network device to which the terminal device moves, that is, the target access network device is in the service area of the I-UPF. Network equipment can be connected with I-UPF. In this application, the connection between the target access network device and the I-UPF can be understood as an N3 tunnel or a GTP-U tunnel can be established between the two for data transmission. In this application, the source access network device may refer to the access network device that establishes a PDU session for the terminal device through the access network device; the target access network device may refer to the access network device after the terminal device is switched due to movement .

In the embodiment of the present application, the SMF controlling the PSA UPF may refer to: between the SMF and the PSA UPF, the N4 session message (N4 session message) or the packet forwarding control protocol (packet forwarding control protocol, PFCP) session message (PFCP session message) can be passed between the SMF and the PSA UPF. to interact. Similarly, the I-SMF controlling the I-UPF may refer to: the I-SMF and the I-UPF may interact through N4 session messages or PFCP session messages. Wherein, the N4 session message, for example, can be an N4 session modification request/response (N4 session/modification request/response), or an N4 session establishment request/response (N4 session establishment request/response), or an N4 session release request/response (N4 session establishment request/response). session release request/response). PFCP session message, for example, can be PFCP session modification request/response (PFCP session modification request/response), or PFCP session establishment request/response (PFCP session establishment request/response), or PFCP session release request/response (PFCP session release request /response).

The embodiment of the present application also relates to network elements related to multicast/broadcast services such as MB-SMF1 , MB-UPF1 , MB-SMF2 and MB-UPF2 . Among them, MB-SMF1 can be used to control MB-UPF1, and MB-SMF1 refers to realizing the control plane function of the first multicast/broadcast service in the first service area of the first multicast/broadcast service where the source access network device is located , responsible for managing the MB-SMF of the first multicast/broadcast service/group/session; correspondingly, MB-UPF refers to implementing the first The user plane function of the multicast/broadcast service is responsible for transmitting the MB-UPF of the data of the first multicast/broadcast service.

MB-SMF2 is used to control MB-UPF2. MB-SMF2 refers to realizing the control plane function of the first multicast/broadcast service in the second service area of the first multicast/broadcast service where the target access network device is located, responsible for managing the first multicast broadcast service/group/ MB-SMF of the session; correspondingly, MB-UPF2 refers to realizing the user plane function of the first multicast/broadcast service in the second service area of the first multicast/broadcast service where the target access network device is located, responsible for the transmission MB-UPF of the data of the first multicast/broadcast service.

It should be noted that MB-SMF1 and MB-SMF1 may be the same or different MB-SMFs, and similar MB-UPF1 and MB-UPF2 may also be the same or different MB-UPFs, which is not limited in this application.

The foregoing first information may include information of the first multicast/broadcast service. The information of the first multicast/broadcast service may include one or more of the following information: identification information of the first multicast/broadcast service, identification information (such as area session ID) of the area session of the first multicast/broadcast service , Multicast/broadcast quality of service (quality of service, QoS) information of the first multicast/broadcast service, unicast QoS information corresponding to the multicast/broadcast QoS information of the first multicast/broadcast service.

Wherein, the identification information of the multicast/broadcast service may include: context information (MBS session context) of the multicast/broadcast session, IP multicast address information (IP Multicast address) corresponding to the multicast/broadcast service, multicast/broadcast session The identification information of the associated PDU session (such as PDU session ID), the service data flow (service data flow, SDF) identification rule of the multicast/broadcast service, the packet filter (packet filter) information of the data of the multicast/broadcast service, group The identification information of the multicast/broadcast group corresponding to the multicast/broadcast service (such as the temporary mobile group identifier (TMGI) of the multicast/broadcast group), the multicast/broadcast service session identifier (multicast/broadcast service session ID, MBS session ID), the Internet protocol (internet protocol, IP) address of the application server (such as AF) that provides multicast/broadcast service data, the service identifier (service identifier, service ID) of the multicast/broadcast service, One or more of a source specific IP multicast/broadcast address (source specific IP multicast address), and a multicast/broadcast service packet detection rule (packets detection rule, PDR), which are not limited herein. It should be understood that the PDR is a collection of filters, each filter is a quintuple, and each filter includes the source address, destination address, source port number, destination port number, and protocol number of the multicast service, and the PDR is used for Filter the data of the multicast service.

The regional session means that the same multicast/broadcast service corresponds to different regional sessions in different regions, and is used to distribute different content, that is, the same multicast/broadcast service has the same multicast/broadcast service in different regions The identification information (such as MBS session ID), and the identification information of different area sessions (such as area session ID). For example, the national weather forecast is a multicast/broadcast service, and the multicast/broadcast service distributes different weather forecast contents in different regions.

Optionally, the first information further includes first indication information, and the first indication information is used to trigger the I-SMF to establish the first communication between the I-UPF and MB-UPF2 for transmitting the data of the first multicast/broadcast service. tunnel, or the first indication information is used to query the I-SMF whether the first tunnel has been established, or the first indication information is used to trigger the I-SMF to perform path optimization for the first multicast/broadcast service. The first indication information may also be called a tunnel establishment indication, a tunnel query indication, or a path optimization indication. It should be noted that the above-mentioned first tunnel refers to a directly connect (directly connect or direct connection) tunnel between I-UPF and MB-UPF2. That is, the I-UPF and the MB-UPF do not pass through other network element nodes. When the data of the multicast/broadcast service is transmitted through the first tunnel, the data of the multicast/broadcast service does not need to be forwarded by other network element nodes (such as UPF).

Exemplarily, the first information above may be carried in a PDU session context update request/response message (Nsmf_PDUSession_UpdateSMContext Request/Response), a PDU session update request/response message (Nsmf_PDUSession_Update Request/Response), or a PDU session context request/response message (Nsmf_PDUSession_Context Request/Response) and other messages or signaling may also be sent in other messages or signaling newly introduced during the mobility process of the terminal device, which is not limited in this application.

Step 402, the I-SMF sends the second information to the SMF.

Correspondingly, the SMF receives the second information from the I-SMF.

Wherein, the I-SMF is used to control the I-UPF.

Wherein, the second information may be used to indicate that the first tunnel has been established, and the first tunnel is a tunnel for transmitting the first multicast/broadcast service data between I-UPF and MB-UPF2.

Optionally, the second information may further include information about the above-mentioned first multicast/broadcast service.

In addition, the second information may also be used to indicate support for path optimization for the first multicast/broadcast service, or to indicate that path optimization for the first multicast/broadcast service has been completed, or to indicate that the first multicast/broadcast service The data transmission path of the service does not pass through the PSA UPF, or it is used to indicate that the I-SMF supports multicast/broadcast.

It should be noted that the above indication function of the second message may be embodied in various ways. For example, the above content may be implicitly indicated by carrying the information of the above first multicast/broadcast service in the second information. Alternatively, the above content may also be explicitly indicated by carrying a special indication information or notification information in the second information.

Exemplarily, the second information may be carried in a PDU session update request/response message (Nsmf_PDUSession_Update Request/Response), a PDU session creation request/response message (Nsmf_PDUSession_Create Request/Response), or a PDU session context update request/response message (Nsmf_PDUSession_UpdateSMContext Request /Response) and other messages or signaling, or may be sent in other messages or signaling newly introduced during the mobility process of the terminal device, which is not limited in this application.

In the embodiment of the present application, after the I-SMF receives the first information, if the I-SMF supports multicast/broadcast (that is, has the related processing capability of multicast/broadcast), then the I-SMF can carry the information based on the first information. The first multicast/broadcast service information and/or the first indication information query whether the first tunnel has been established. If not established, the I-SMF establishes the first tunnel to optimize the data transmission path of the first multicast/broadcast service. Furthermore, the I-SMF may send second information to the SMF to notify the SMF that the first tunnel has been established, or that it supports path optimization for the first multicast/broadcast service, or that the path optimization for the first multicast/broadcast service has been completed. Finish. Through the above process, the SMF can know that the I-SMF has the ability to process multicast/broadcast services, and can optimize the transmission path of the first multicast/broadcast service.

Exemplarily, the establishment of the first tunnel by the I-SMF may be: the I-SMF establishes the first tunnel through interaction with the MB-SMF. Specifically, it may include:

When the first tunnel adopts unicast transmission mode, I-SMF passes N4 session modification request (N4 session modification request) or N4 session establishment request (N4 session establishment request) or PFCP session modification request (PFCP session modification request) or PFCP The session establishment request (PFCP session establishment request) requests the I-UPF to allocate the first tunnel information, and the I-UPF passes the N4 session modification response (N4 session modification response) or the N4 session establishment response (N4 session establishment response) or the PFCP session modification response (PFCP session modification response) or PFCP session establishment response (PFCP session establishment response) to send the allocated first tunnel information to the I-SMF. The first tunnel information may include a tunnel endpoint identifier (tunnel endpoint identifier, TEID) of the first tunnel and/or an IP address of the I-UPF. After that, the I-SMF sends the first tunnel information to the MB-SMF through the control plane signaling. The control plane signaling can be, for example: group/broadcast service data reception request, Nmbsmf_Reception_Request request; multicast/broadcast session context update request , Nmbsmf_MBSSession_ContextUpdate request; multicast broadcast context status subscription, Nmbsmf_MBSSession_ContextStatusSubscribe; multicast/broadcast session creation request, Nmbsmf_MBSSession_Create request; multicast/broadcast session update request, Nmbsmf_MBSSession_Update request; multicast/broadcast session status subscription, Nmbsmf_MBSSession_StatusSubscribe. MB-SMF further sends the first tunnel information to MB-UPF through N4mb session modification request (N4mb session modification request) or N4mb session establishment request (N4mb session establishment request), so that MB-UPF can send the first tunnel information to I-UPF Data for multicast/broadcast services.

When the first tunnel adopts the multicast transmission mode, the I-SMF sends data requesting to receive the multicast/broadcast service to the MB-SMF through the control plane signaling, wherein the control plane signaling can be, for example: multicast/broadcast service data Receive request, Nmbsmf_Reception_Request request; Multicast/broadcast session context update request, Nmbsmf_MBSSession_ContextUpdate request; Multicast broadcast context status subscription, Nmbsmf_MBSSession_ContextStatusSubscribe; Multicast/broadcast session creation request, Nmbsmf_MBSession_Create request; Multicast/broadcast session update request, Nmbsmf_MBSSession_Update; broadcast/broadcast session status subscription, Nmbsmf_MBSSession_StatusSubscribe). Further, the MB-SMF sends the first tunnel information to the I-SMF through the multicast/broadcast service data reception response, where the first tunnel information may include the TEID of the first tunnel and/or the IP address of the MB-UPF, where the group The broadcast/broadcast service data reception response may be, for example: Nmbsmf_Reception_Request response; Nmbsmf_MBSSession_ContextUpdate response; Nmbsmf_MBSSession_ContextStatusNotify; Nmbsmf_MBSession_Create response; Nmbsmf_MBSSession_Update response; After I-SMF receives the first tunnel information, through N4 session modification request (N4 session modification request) or N4 session establishment request (N4 session establishment request) or PFCP session modification request (PFCP session modification request) or PFCP session establishment request ( PFCP session establishment request) sends the allocated first tunnel information to the I-UPF, so that the I-UPF can receive the data of the first multicast/broadcast service sent by the MB-UPF.

The effect of performing path optimization on the first multicast/broadcast service can be shown in FIG. 5 . The data transmission path of the first multicast/broadcast service before optimization is: MB-UPF2–>PSA UPF–>I-UPF–>target access network equipment. The data transmission path of the first multicast/broadcast service after optimization is: MB-UPF2–>I-UPF–>target access network equipment. It can be seen that the data transmission path of the first multicast/broadcast service after optimization saves two hop transmission paths from MB-UPF2 to PSA UPF and from PSA UPF to I-UPF. It can be understood that the multicast/broadcast service usually refers to data transmission in the downlink direction, so the above optimization process is described by taking the path optimization in the downlink direction as an example. If there is a multicast broadcast service in the uplink direction, its optimization The process is similar to that in the downlink direction and will not be repeated here.

Further, as shown in optional step 403 in Figure 4, after the SMF receives the second information from the I-SMF, the SMF can also send a first message to the PSA UPF according to the second information, and the first message uses To trigger the PSA UPF to release (release) the resources used to transmit the first multicast/broadcast service data. The "release" can also be understood as removing or deactivating. The "resource" may include PDR, forwarding action rules (forwarding action rules, FAR), QoS enforcement rule (QoS enforcement rule, QER), etc. set by the PSA UPF for transmitting the data of the first multicast/broadcast service. The first message may be an N4 session modification request (N4 session modification request) message, or an N4 session establishment request (N4 session establishment request), or a PFCP session modification request (PFCP session modification request) message, or a PFCP session establishment request (PFCP session establishment request) message.

Similarly, as shown in optional step 404 in FIG. 4, after the I-SMF determines that the first tunnel has been established (for example, it may be after the first tunnel is established, or after the first tunnel is determined to exist through an inquiry), A second message may also be sent to the I-UPF, where the second message is used to trigger the I-UPF to configure resources for transmitting the data of the first multicast/broadcast service. The "configuration" can also be understood as meanings such as adding (add) or activating (activate). As mentioned above, the resources may include PDR, FAR, QER, etc. corresponding to the transmission of the first multicast/broadcast service data. The second message can be an N4 session modification request (N4 session modification request) message, or an N4 session establishment request (N4 session establishment request), or a PFCP session modification request (PFCP session modification request) message, or a PFCP session establishment request (PFCP session establishment request) message.

It should be noted that step 404 is executed after step 401, but the present application does not specifically limit the sequence of execution between step 404, step 402, and step 403.

Optionally, as shown in optional step 400 in Figure 4, before the SMF sends the first information to the I-SMF, the I-SMF may send its own multicast/broadcast capability information to the SMF, and the multicast/broadcast capability information It is used to indicate whether the I-SMF supports multicast/broadcast (that is, whether it supports multicast/broadcast processing, or whether it has the function of processing multicast/broadcast). After receiving the multicast/broadcast capability information of the I-SMF, the SMF may send the first information to the I-SMF if it is determined according to the multicast/broadcast capability information that the I-SMF supports multicast/broadcast.

In the above technical solution, when the terminal device moves to the service area of the I-UPF controlled by the I-SMF, the SMF can send the first multicast/broadcast service information and/or the first indication information to the I-SMF to trigger the I-SMF A first tunnel for transmitting the data of the first multicast/broadcast service is established between the I-UPF and the MB-UPF, so as to optimize the transmission path for the first multicast/broadcast service by using the first tunnel. In this way, the data of the first multicast/broadcast service can no longer be forwarded through the PSA UPF, thereby reducing the transmission delay of the multicast/broadcast service data and saving network transmission resources.

The above-mentioned technical solutions of the present application can be applied to scenarios of inserting an I-SMF and replacing an I-SMF. Among them, the scenario of replacing the I-SMF refers to that, as the terminal device continues to move, when the terminal device moves out of the service area of the source I-SMF (that is, the target access network device to which the terminal device recently moves can neither be controlled by the SMF) When the service area of the UPF is not covered by the service area of all UPFs controlled by the source I-SMF), the I-SMF and I-UPF can be replaced. In this way, the I-SMF before the replacement can be called the source I-SMF, the I-UPF before the replacement can be called the source I-UPF, the I-SMF after the replacement can be called the target I-SMF, and the I-UPF after the replacement can be called the source I-UPF. It can be called the target I-UPF.

In the scenario of replacing the I-SMF, a possible implementation manner is that the related steps performed by the SMF shown in Figure 4 above can be performed by the source I-SMF, and the related steps performed by the I-SMF can be performed by the target I-SMF. SMF, the corresponding method flow can be shown as step 601 to step 604 in FIG. 6 , which will not be repeated here. It can be understood that, in this embodiment, the first tunnel refers to the tunnel between the target I-UPF and MB-UPF2, and the so-called path optimization means that as shown in Figure 7, the transmission path consists of the previous MB-UPF2->PSA UPF->target I-UPF–>target access network equipment, optimized to MB-UPF2–>target I-UPF–>target access network equipment. In addition, in this embodiment, both the source I-SMF and the target I-SMF support multicast/broadcast.

Another possible implementation is that if the source I-SMF does not support multicast/broadcast, the target I-SMF cannot interact with the source I-SMF to execute the process shown in Figure 6, and obtain the first Information about multicast/broadcast services. Therefore, as shown in steps 800 to 804 in FIG. 8, the target I-SMF may first send multicast/broadcast capability information to the SMF to notify the SMF that it supports multicast/broadcast. Furthermore, the SMF may send the first information to the target I-SMF according to the capability information, which carries the information of the first multicast/broadcast service and/or the first indication information to indicate that the target I-SMF is the first multicast/broadcast service. Path optimization for broadcasting services. After the path optimization is completed, the target I-SMF may send second information to the SMF to notify the SMF that the first tunnel has been established. Subsequently, the SMF can send the first message to the PSA UPF to trigger the PSA UPF to release the resources used to transmit the data of the first multicast/broadcast service, and the target I-SMF can also send the second message to the target I-UPF to trigger the target I-UPF - The UPF configures resources for the first multicast/broadcast service.

It should be noted that the technical solutions of the embodiments of the present application can be applied in the handover process or service request (service request, SR) process involved in the mobile process of the terminal equipment. The technical solutions of the embodiments of the present application will be exemplarily described below in conjunction with various processes that may be involved in the moving process of the terminal device.

It should be understood that the following examples are only some scenarios that may be applied in the embodiments of this application, and this application includes but is not limited to them. In addition, the source AMF in the following example can also be called the old AMF (old AMF), the target AMF can also be called the new AMF (new AMF), similarly, the source I-SMF can also be called the old I-SMF (old I-SMF) -SMF), the target I-SMF can also be called new I-SMF (new I-SMF), the source I-UPF can also be called old I-UPF (old I-UPF), and the target I-UPF can also be called New I-UPF (new I-UPF).

Example 1: Scenario where UE performs Xn handover and inserts I-SMF

Step 901, the target access network device sends an N2 path switch request (N2 path switch request) to the AMF.

The N2 path switching request may include UE location information and tunnel information allocated by the target access network device.

The location information of the UE may include one or more pieces of information such as identification information of a tracking area, identification information of an access network device, or identification information of a cell. Specifically, the location information of the UE may be UE location information.

The tunnel information allocated by the target access network device may be downlink tunnel information, which is used to establish a tunnel from the I-UPF to the target access network device, so that the I-UPF sends data to the target access network device. Specifically, the tunnel information allocated by the target access network device may be access network tunnel information AN tunnel Info.

It should be noted that step 901 may be performed after the UE completes the handover, where the UE completes the handover may mean that the UE successfully accesses the target access network device.

In step 902, the AMF sends a PDU session context update request to the SMF.

Specifically, the PDU session context update request may be a session management context update request, such as Nsmf_PDUSession_UpdateSMContext Request.

Wherein, the PDU session context update request may include the identification (such as QoS flow ID) of the QoS flow whose air interface resource allocation fails.

Correspondingly, after receiving the PDU session context update request, the SMF can initiate a PDU session modification process to trigger deletion of the QoS flow that fails to allocate air interface resources.

In step 903, the AMF selects an I-SMF according to the location information of the UE.

It should be pointed out that since the PSA PDU controlled by the SMF cannot be directly connected to the target access network device, the AMF may perform step 904 to select the I-SMF according to the location information of the UE.

Specifically, the AMF may select an SMF whose service area can cover the location of the UE as the I-SMF according to the location information of the UE.

In step 904, the AMF sends a PDU session context creation request to the I-SMF.

Specifically, the PDU session context creation request may be Nsmf_PDUSession_CreateSMContext Request.

The PDU session context creation request may include UE identification information (such as user permanent identifier (subscription permanent identifier, SUPI)), UE location information, AMF ID, SMF ID, session management context identification (session management context ID, SM context ID) and the tunnel information assigned by the target access network device.

In step 905, the I-SMF sends a PDU session context request to the SMF.

Specifically, the PDU session context request can be Nsmf_PDUSessionContextRequest Request.

The PDU session context request may include a session management context type (session management context type, SM context type) and a session management context identifier, and the session management context type and the session management context identifier may be used by the I-SMF to obtain the session management context from the SMF.

In step 906, the SMF determines that the PDU session corresponding to the session management context identifier is associated with the multicast/broadcast service, and the SMF sends a PDU session context response to the I-SMF.

Specifically, the PDU session context response may be Nsmf_PDUSessionContextRequest Response.

Exemplarily, the SMF can obtain the session management context of the PDU session requested by the I-SMF according to the session management context type and the session management context identifier. In one embodiment, if the session management context includes identification information of the multicast/broadcast service (such as MBS session ID), the SMF can determine that the PDU session is associated with the multicast/broadcast service. In another embodiment, the multicast/broadcast session context of the multicast/broadcast service is stored in the SMF. If the multicast/broadcast session context includes UE identification information (such as SUPI), the SMF can determine the PDU session Associated with multicast/broadcast services. Furthermore, after determining that the PDU session is associated with the multicast/broadcast service, the SMF may send a PDU session context response to the I-SMF, and the PDU session context response may include the session management context.

The PDU session context response may also include first information. For the introduction of the first information, please refer to the relevant description above, and details will not be repeated here.

Optionally, if the information of the multicast/broadcast service included in the first information only includes identification information of the multicast/broadcast service, the I-SMF may, according to the location information of the UE, the session identifier of the multicast/broadcast service (such as MBS session ID ), choose MB-SMF through NRF or UDM. The I-SMF can obtain the multicast/broadcast QoS information of the multicast/broadcast service from the MB-SMF, and generate unicast QoS information corresponding to the multicast/broadcast QoS information.

If the I-SMF supports multicast/broadcast, then the following steps 908 to 918 are performed:

In step 907, the I-SMF interacts with the MB-SMF to establish a tunnel between the I-UPF and the MB-UPF for transmitting the multicast/broadcast service.

The tunnel may be, for example, the first tunnel described above.

In step 908, the I-SMF sends an N4 session establishment request (N4 session Eestablishment request) to the I-UPF.

The N4 session establishment request may include tunnel information allocated by the target access network device. Optionally, if the tunnel information of the I-UPF is allocated by the I-UPF, the I-SMF may also request the I-UPF to allocate tunnel information through the N4 session establishment request, and the tunnel information may be the core network tunnel information CN tunnel Info.

In step 909, the I-UPF sends an N4 session establishment response (N4 session establishment response) to the I-SMF.

Optionally, if the tunnel information of the I-UPF is allocated by the I-UPF, the N4 session creation response also includes the tunnel information allocated by the I-UPF, and the tunnel information may be the core network tunnel information CN tunnel Info. The tunnel information allocated by the I-UPF may include uplink tunnel information (for example, UL CN tunnel Info) and downlink tunnel information (for example, DL CN tunnel Info). Wherein, the uplink tunnel information is used to establish a tunnel from the target access network device to the I-UPF, so that the target access network device sends data to the I-UPF. The downlink tunnel information is used to establish a tunnel from PSA UPF to I-UPF so that PSA UPF can send data to I-UPF.

In step 910, the I-SMF sends a PDU session creation request to the SMF.

Specifically, the PDU session creation request may be Nsmf_PDUSession_Create Request.

The PDU session creation request may include UE identification information, UE location information, PDU session identification information (such as PDU session ID), downlink tunnel information allocated by I-UPF, and the like.

Optionally, if the I-SMF receives the first information sent by the SMF in step 907, the PDU session creation request also includes second information, and the second information is used to indicate that the I-UPF and the MB-UPF use The tunnel for transmitting the multicast/broadcast service has been established. For the introduction of the second information, please refer to the relevant description above, and details will not be repeated here.

Step 911, if the SMF receives the second information, the SMF sends an N4 session modification request (N4 session modification request) to the PSA UPF.

The N4 session modification request may include downlink tunnel information allocated by the I-UPF.

The SMF can also request the PSA UPF to allocate tunnel information through the N4 session modification request, and the tunnel information can be the core network tunnel information CN tunnel Info. The tunnel information may be uplink tunnel information, which is used for I-UPF to send data to PSA UPF. The tunnel information allocated by the PSA UPF will be sent to the I-SMF through the PDU session context creation response in step 915, and then sent to the I-UPF by the I-SMF.

The N4 session modification request may be the first message mentioned in the above embodiment, and the N4 session modification request is used to trigger the PSA PDU to release the resources used to transmit the data of the multicast/broadcast service. For the introduction of the first message, please refer to the relevant description above, and details will not be repeated here.

Step 912, PSA UPF sends N4 session modification response (N4 session modification response) to SMF.

In step 913, the SMF sends a PDU session creation response to the I-SMF.

Specifically, the N4 session modification response may be Nsmf_PDUSession_Create Response.

Step 914, I-SMF sends N4 session modification request (N4 session modification request) to I-UPF.

The N4 session modification request may include tunnel information allocated by the PSA UPF, and the tunnel information is used to establish a tunnel from the I-UPF to the PSA UPF so that the I-UPF sends data to the PSA UPF.

Step 915, I-UPF sends N4 session modification response (N4 session modification response) to I-SMF.

In step 916, the I-SMF sends a PDU session context creation response to the AMF.

Specifically, the PDU session context creation response may be Nsmf_PDUSession_CreateSMContext Response.

Optionally, the PDU session context creation response may include I-UPF uplink tunnel information.

In step 917, the AMF sends an N2 path switching response to the target access network device.

Specifically, the N2 path switch response may be N2 path switch request ack.

Optionally, the N2 path switching response may include uplink tunnel information allocated by the I-UPF.

Example 2: The scenario where UE performs N2 handover and inserts I-SMF

Step 1001, the source access network device sends a handover required to a source AMF (source AMF, S-AMF).

Exemplarily, the handover needs may include N2 session management information (that is, N2 SM Information), the N2 session management information includes the PDU session information of the UE to be handed over, and the PDU session information includes the PDU session identifier and the PDU session contained in the PDU session QoS information corresponding to the unicast QoS flow. Wherein, the QoS information of the unicast QoS flow includes a quality of service flow index (QoS flow identifier, QFI) and QoS parameters. If the PDU session of the currently switched UE is associated with the multicast/broadcast service, the PDU session information also includes information about the unicast QoS flow to which the multicast/broadcast QoS flow is mapped.

The handover requirement may also include location information of the UE. The location information of the UE may include one or more pieces of information such as a tracking area identifier, an access network device identifier, or a cell identifier. Specifically, the location information may refer to the location information (namely target ID) of the UE under the target access network device, and the structure of the information element is defined in 3GPP technical specification (technical specification, TS) 38.413.

If the N2 session management information indicates that there is no direct forwarding tunnel between the source access network device and the target access network device, it means that an indirect forwarding tunnel can be established between the source access network device and the target access network device. At this time, the N2 session The management information may also include indirect forwarding tunnel information allocated by the source access network device.

The handover requirement may also include the identifier of the QoS flow that the source access network device wishes to forward through the forwarding tunnel. If the multicast/broadcast QoS flow needs to be forwarded through the forwarding tunnel, the switching requirement may further include the QFI of the unicast QoS flow corresponding to the multicast/broadcast QoS flow.

Step 1002, the source AMF selects a target AMF (target-AMF, T-AMF) according to the location information of the UE.

Wherein, the target AMF is connected to the target access network device.

Specifically, the source AMF may select another AMF whose service area can cover the location of the UE as the target AMF according to the location information of the UE.

Step 1003, the source AMF sends a UE context creation request to the target AMF.

Specifically, the UE context creation request may be Namf_Communication_CreateUEContext Request.

The UE context creation request may include the handover UE context information stored by the source AMF, and may also include the information sent to the source AMF by the source access network device in step 1001 .

Step 1004, the target AMF selects an I-SMF according to the location information of the UE.

It should be pointed out that since the PSA PDU controlled by the SMF (that is, the anchor SMF (anchor SMF, A-SMF)) cannot be directly connected to the target access network device (that is, the location of the UE can no longer be served by all UPFs controlled by the SMF) area coverage), therefore, the target AMF may perform step 1004 to select an I-SMF according to the location information of the UE.

Step 1005, the target AMF sends a PDU session context creation request to the I-SMF.

The PDU session context creation request may include UE identification information (such as SUPI), UE location information, AMF ID, SMF ID, session management context identification, and the like.

In step 1006, the I-SMF sends a PDU session context request to the SMF.

Specifically, the PDU session context request can be Nsmf_PDUSessionContext Request.

The PDU session context request may include a session management context type and a session management context identifier, and the session management context type and the session management context identifier are used for the I-SMF to obtain the session management context from the SMF.

Step 1007, SMF sends PDU session context response to I-SMF.

Specifically, the PDU session context response may be Nsmf_PDUSessionContext Response.

Exemplarily, the SMF may determine the session management context requested by the I-SMF according to the session management context type and the session management context identifier, and then send a PDU session context response to the I-SMF, where the PDU session context response includes the session management context.

In step 1008, the I-SMF sends an N4 session establishment request (N4 session establishment request) to the I-UPF.

The N4 session establishment request is used to request the I-UPF to allocate tunnel information used by the PSA UPF, also called downlink tunnel information. Specifically, the tunnel information is core network tunnel information CN tunnel Info.

In step 1009, the I-UPF sends an N4 session establishment response (N4 session establishment response) to the I-SMF.

The N4 session establishment response may include tunnel information allocated by the I-UPF (ie downlink tunnel information). The tunnel information allocated by the I-UPF is used to establish a tunnel from the PSA UPF to the I-UPF so that the PSA UPF can send data to the I-UPF.

In step 1010, the I-SMF sends a PDU session creation request to the SMF.

The PDU session creation request may include tunnel information allocated by the I-UPF (ie downlink tunnel information).

Step 1011, SMF sends N4 session modification request (N4 session modification request) to PSA UPF.

The N4 session modification request may include tunnel information allocated by the I-UPF (ie downlink tunnel information). Optionally, the SMF may also request the PSA UPF to allocate tunnel information through the N4 session modification request, specifically, the tunnel information may be the core network tunnel information CN tunnel Info.

Step 1012, PSA UPF sends N4 session modification response (N4 session modification response) to SMF.

The N4 session modification response may include tunnel information allocated by the PSA UPF, and the tunnel information allocated by the PSA UPF is used to establish a tunnel from the I-UPF to the PSA UPF, so that the I-UPF sends data to the PSA UPF.

In step 1013, the SMF sends a PDU session creation response to the I-SMF.

Specifically, the PDU session creation response may be Nsmf_PDUSession_Create Response.

The PDU Session Creation Response may include tunnel information allocated by the PSA UPF.

Step 1014, I-SMF sends N4 session modification request (N4 session modification request) to I-UPF.

The N4 session modification request may include tunnel information allocated by the PSA UPF. In addition, the I-SMF may request the I-UPF to allocate tunnel information used by the target access network device through the N4 session modification request, also called uplink tunnel information. Specifically, the tunnel information may be CN tunnel Info.

Step 1015, I-UPF sends N4 session modification response (N4 session modification response) to I-SMF.

The N4 session modification response may include tunnel information (that is, uplink tunnel information) allocated by the I-UPF, and the tunnel information allocated by the I-UPF is used to establish a tunnel from the target access network device to the I-UPF, so that the target access network device Send data to I-UPF.

In step 1016, the I-SMF sends a PDU session context creation response to the target AMF.

Specifically, the PDU session context creation response may be Nsmf_PDUSession_Create Response.

The PDU session context creation response may include tunnel information allocated by the I-UPF (ie, uplink tunnel information), and may also include N2 session management information in step 1001 .

Step 1017, the target AMF sends a handover request (handover request) to the target access network device.

The handover request may include tunnel information allocated by the I-UPF (that is, uplink tunnel information), and may also include N2 session management information.

Step 1018, the target access network device sends a handover request response to the target AMF.

Specifically, the handover request response may be a handover request ACK.

The handover request response may include tunnel information allocated by the target access network device, and the tunnel information allocated by the target access network device is used to establish a tunnel from the I-UPF to the target access network device, so as to communicate with the I-UPF to the target access network. network device to send data. Specifically, the tunnel information may be AN tunnel Info.

The handover request response may also include identification information of unicast QoS flows whose air interface resources are successfully created. Exemplarily, the target access network device may allocate corresponding air interface resources according to the QoS information corresponding to the unicast QoS flow included in the N2 session management information, such as data radio bearer (data radio bearer, DRB) configuration information. The DRB configuration information may include configuration information from the PDCP layer to the PHY layer, such as whether encryption is required at the PDCP layer, whether the RLC layer adopts acknowledged mode (acknowledged mode, AM) mode or unacknowledged mode (unacknowledged mode, UM) mode, MAC layer Scheduling strategies, modulation and coding methods of the PHY layer, etc.

The handover request response may also include access configuration information, which is used for the UE to access the target access network device. For example, the access configuration information may include cell radio network temporary identifier (C-RNTI), radio bearer configuration information of the unicast QoS flow, and unicast QoS flow corresponding to the multicast/broadcast QoS flow Radio bearer configuration information. If the target access network device supports multicast/broadcast, the access configuration information may also include radio bearer configuration information of the multicast/broadcast QoS flow.

Step 1019, the target AMF sends a PDU session context update request to the I-SMF.

Specifically, the PDU session context update request may be Nsmf_PDUSession_Update Request.

The PDU session context update request may include tunnel information allocated by the target access network device, and may also include access configuration information.

Step 1020, I-SMF sends N4 session modification request (N4 session modification request) to I-UPF.

The N4 session modification request may include tunnel information allocated by the target access network device.

Step 1021, I-UPF sends N4 session modification response (N4 session modification response) to I-SMF.

In step 1022, the I-SMF sends a PDU session context update response to the target AMF.

Specifically, the PDU session context update response may be Nsmf_PDUSession_Update Response.

The PDU session context update response may include access configuration information.

Step 1023, the target AMF sends a UE context creation response to the source AMF.

Specifically, the UE context creation response may be Namf_Communication_CreateUEContext Response.

The UE context creation response may include access configuration information.

Step 1024, the source AMF sends a handover command (handover command) to the source access network device.

The switching command may include access configuration information.

Step 1025, the source access network device sends a handover command (handover command) to the UE.

The switching command may include access configuration information.

Step 1026, the UE accesses the target access network device according to the access configuration information, and receives service data from the target access network device.

The service data may be, for example, multicast/broadcast service data.

It should be pointed out that if the target access network device does not support multicast/broadcast, the target access network device sends multicast/broadcast service data to the UE through the PDU session.

Step 1027, the target access network device sends a handover notification (handover notify) to the target AMF.

The handover notification is used to notify the target AMF that the UE has successfully handed over to the target access network device.

Step 1028, the target AMF sends a PDU session context update request to the I-SMF.

The PDU session context update request is used to notify the UE of successful handover to the target access network device.

In step 1029, the I-SMF interacts with the MB-SMF to establish a first tunnel.

For the introduction of the first tunnel, please refer to the relevant description above, and details will not be repeated here.

Step 1030, the I-SMF sends a PDU session update request to the SMF.

Specifically, the PDU session update request may be Nsmf_PDUSession_Update Request.

The PDU session update request may include second information. For the introduction of the second information, please refer to the relevant description above, and details will not be repeated here.

Step 1031, SMF sends N4 session modification request (N4 session modification request) to PSA UPF.

Example 3: Scenario where UE performs N2 handover and replaces I-SMF

Step 1101, the source access network device sends a handover required to the source AMF.

For the specific implementation manner of step 1101, please refer to the related description in step 1001, and details will not be repeated here.

Step 1102, the source AMF selects the target AMF according to the location information of the UE.

For the specific implementation manner of step 1102, please refer to the relevant description in step 1002, and details will not be repeated here.

Step 1103, the source AMF sends a UE context creation request to the target AMF.

The UE context creation request may include the handover UE context information stored by the source AMF, and may also include the information sent to the source AMF by the source access network device in step 1101 .

Step 1104, the target AMF selects the target I-SMF according to the location information of the UE.

It should be pointed out that since the PSA PDU controlled by the SMF (that is, A-SMF) cannot be directly connected to the target access network device (it can be understood that the location of the UE is outside the service area of all UPFs controlled by the SMF), The target AMF may execute step 1104 to select a target I-SMF.

Specifically, the target AMF may select an SMF whose service area can cover the location of the UE as the target I-SMF according to the location information of the UE.

Step 1105, the target AMF sends a PDU session context creation request to the target I-SMF.

Specifically, the PDU session context creation request can be Nsmf_PDUSession_CreateSMContext Request.

Step 1106, the target I-SMF sends a PDU session context request to the source I-SMF.

It should be noted that, if the source I-SMF does not support multicast/broadcast, continue to perform step 1107-step 1127.

Step 1107, the source I-SMF sends a PDU session context response to the target I-SMF.

Specifically, the PDU session context response can be Nsmf_PDUSessionContext Response.

It should be noted that, since the source I-SMF does not support multicast/broadcast, the PDU session context response does not include the first information. For the introduction of the first information, please refer to the relevant description above, and details will not be repeated here.

Step 1108, the target I-SMF sends an N4 session establishment request (N4 session establishment request) to the target I-UPF.

The N4 session establishment request is used to request the target I-UPF to allocate tunnel information, specifically, the tunnel information may be core network tunnel information CN tunnel Info.

Step 1109, the target I-UPF sends an N4 session establishment response (N4 session establishment response) to the target I-SMF.

The N4 session establishment response includes the tunnel information assigned by the target I-UPF. The tunnel information allocated by the target I-UPF may include uplink tunnel information and downlink tunnel information. Among them, the uplink tunnel information is used to establish a tunnel from the target access network device to the I-UPF so that the target access network device can send data to the I-UPF; the downlink tunnel information is used to establish a tunnel from the PSA UPF to the I-UPF so that the PSA UPF sends data to I-UPF.

Step 1110, the target I-SMF sends multicast/broadcast capability information to the SMF.

The multicast/broadcast capability information is used to indicate that the target I-SMF supports multicast/broadcast. The multicast/broadcast capability information may be sent in an N16 message or N16a message, or in other new messages, which is not limited in this application.

It should be noted that step 1110 may be performed after step 1107 or step 1108 or step 1109, which is not specifically limited in this application.

Step 1111, the SMF determines that the PDU session is associated with the multicast/broadcast service, and sends the first information to the target I-SMF.

For the introduction of the first information, please refer to the relevant description above, and details will not be repeated here.

The first information may be sent in an N16 message or N16a message, or in other new messages, which is not limited in this application.

Step 1112, the target I-SMF sends a PDU session context creation response to the target AMF.

Specifically, the PDU session context creation response can be Nsmf_PDUSession_Create Response.

The PDU session context creation response may include the tunnel information allocated by the I-UPF, and also include the N2 session management information in step 1101 .

Step 1113, the target AMF sends a handover request to the target access network device.

The handover request may include tunnel information allocated by the I-UPF, and may also include N2 session management information.

Step 1114, the target access network device sends a handover request response to the target AMF.

Specifically, the handover request response may be a handover request ACK.

The handover request response may include tunnel information allocated by the target access network device, and the tunnel information allocated by the target access network device may be used to establish a tunnel from the I-UPF to the target access network device, so as to communicate with the I-UPF to the target access network device. Network-connected devices send data. Specifically, the tunnel information may be access network tunnel information AN tunnel Info.

The handover request response may also include identification information of unicast QoS flows whose air interface resources are successfully created. Exemplarily, the target access network device allocates corresponding air interface resources according to the QoS information corresponding to the unicast QoS flow included in the N2 session management information, for example, data radio bearer (data radio bearer, DRB) configuration information, the DRB configuration information It can include configuration information from the PDCP layer to the PHY layer, such as whether the PDCP layer needs to be encrypted, whether the RLC layer uses acknowledged mode (acknowledged mode, AM) mode or unacknowledged mode (unacknowledged mode, UM) mode, the scheduling strategy of the MAC layer, Or the modulation and coding mode of the PHY layer, etc.

The handover request response may also include access configuration information, which is used for the UE to access the target access network device. For example, the access configuration information may include at least one of the following information: C-RNTI, radio bearer configuration information of a unicast QoS flow, or radio bearer configuration information of a unicast QoS flow corresponding to a multicast/broadcast QoS flow .

It should be noted that, if the target access network device supports multicast/broadcast, the access configuration information may also include radio bearer configuration information of the multicast/broadcast QoS flow.

Step 1115, the target AMF sends a PDU session context update request to the target I-SMF.

Step 1116, the target I-SMF sends an N4 session modification request (N4 session modification request) to the target I-UPF.

The N4 session modification request includes tunnel information allocated by the target access network device.

Step 1117, the target I-UPF sends an N4 session modification response (N4 session modification response) to the target I-SMF.

Step 1118, the target I-SMF sends a PDU session context update response to the target AMF.

Step 1119, the target AMF sends a UE context creation response to the source AMF.

The UE context creation response may include access configuration information.

Step 1120, the source AMF sends a handover command (handover command) to the source access network device.

The handover command may include access configuration information.

Step 1121, the source access network device sends a handover command (handover command) to the UE.

The handover command may include access configuration information.

Step 1122, the UE accesses the target access network device according to the access configuration information, and receives service data from the target access network device.

The service data may be, for example, multicast/broadcast service data.

It should be pointed out that if the target access network device does not support multicast/broadcast, then the target access network device can send multicast/broadcast service data to the UE through the PDU session.

Step 1123, the target access network device sends a handover notification (handover notify) to the target AMF.

The handover notification is used to notify the target AMF of successful handover to the target access network device.

Step 1124, the target AMF sends a PDU session context update request to the target I-SMF.

Specifically, the PDU session context update request can be used to notify the UE of successful handover to the target access network device.

Step 1125, the target I-SMF interacts with the MB-SMF to establish a first tunnel.

Step 1126, the target I-SMF sends a PDU session update request to the SMF.

Step 1127, SMF sends N4 session modification request (N4 session modification request) to PSA UPF.

Example 4: Scenario where the UE executes the SR procedure

Step 1201, the UE sends a service request (service request) to the access network device.

The service request may include identification information of the UE, location information of the UE, and identification information of a PDU session to be activated (such as a PDU session ID).

Wherein, for the identification information of the UE and the location information of the UE, reference may be made to the foregoing related description, and details are not repeated here.

Step 1202, the access network device sends an N2 message (N2 message) to the AMF.

The N2 message may include UE location information and identification information of a PDU session that needs to be activated.

Step 1203, AMF selects a target I-SMF.

Exemplarily, if the location of the UE is outside the service area of the source I-SMF, the AMF may determine to insert the target I-SMF, and may select the target I-SMF through the NRF. For example, the AMF may select an SMF whose service area can cover the location of the UE as the target I-SMF.

In step 1204, the AMF sends a PDU session context establishment request to the target I-SMF.

Specifically, the PDU session context establishment request may be Nsmf_PDUSession_CreateSMContext Request.

The PDU session context establishment request can include the identification information of the PDU session, the identification information (such as SMF ID) of the source I-SMF.

Step 1205, the target I-SMF sends a PDU session context request to the source I-SMF according to the identification information of the source I-SMF and the identification information of the PDU session.

Specifically, the PDU session context request may be Nsmf_PDUSession_Context Request.

The PDU session context request may include identification information of the PDU session.

If the source I-SMF does not support multicast/broadcast, then continue to perform the following steps 1206 to 1214.

Step 1206, the source I-SMF sends a PDU session context response message to the target I-SMF.

Specifically, the PDU session context response message may be Nsmf_PDUSession_Context Response.

If the target I-SMF supports multicast/broadcast, continue to perform the following steps 1207 to 1214.

Step 1207, the target I-SMF sends an N4 session establishment request (N4 session establishment request) to the target I-UPF.

The N4 session establishment request is used to request the target I-UPF to allocate tunnel information, and the tunnel information allocated by the target I-UPF is used to establish a tunnel between the target I-UPF and the source I-UPF. Specifically, the tunnel information may be core network tunnel information CN tunnel Info.

Step 1208, the target I-UPF sends an N4 session establishment response (N4 session establishment response) to the target I-SMF.

The N4 session setup response may include tunnel information allocated by the target I-UPF.

Step 1209, the target I-SMF sends a PDU session context update request to the source I-SMF.

Specifically, the PDU session context update request may be Nsmf_PDUSession_UpdateSMContext Request.

The PDU session context update request may include tunnel information allocated by the target I-UPF.

Step 1210, the source I-SMF sends an N4 session modification request (N4 session modification request) to the source I-UPF.

The N4 session modification request may include tunnel information allocated by the target I-UPF, so that the source I-UPF can send data to the target I-UPF.

Step 1211, the source I-UPF sends an N4 session modification response (N4 session modification response) to the source I-SMF.

Step 1212, the source I-SMF sends a PDU session context update response to the target I-SMF.

Specifically, the PDU session context update response may be Nsmf_PDUSession_UpdateSMContext Response.

Step 1213, the target I-SMF sends a PDU session update request to the SMF.

If the target I-SMF supports multicast/broadcast, the PDU session update request may include multicast/broadcast capability information, and the multicast/broadcast capability information is used to indicate that the target I-SMF supports multicast broadcast.

Step 1214, the SMF determines that the PDU session is associated with the multicast/broadcast service, and sends a PDU session update response to the target I-SMF.

Specifically, the PDU session update response may be Nsmf_PDUSession_Update Response.

In one embodiment, the SMF can determine that the PDU session is associated with the multicast/broadcast service according to the identification information (such as MBS session ID) of the multicast/broadcast service included in the session management context of the PDU session. In another embodiment, the multicast/broadcast session context of the multicast/broadcast service is stored in the SMF, and the PDU session can be determined according to the identification information (such as SUPI) of the UE included in the multicast/broadcast session context. Multicast/broadcast service association.

The PDU session update response may include first information. For the introduction of the first information, please refer to the relevant description above, and details will not be repeated here.

The embodiment of the present application also provides a communication device. Please refer to FIG. 13 , which is a schematic structural diagram of a communication device provided in the embodiment of the present application. The communication device 1300 includes: a transceiver module 1310 and a processing module 1320 . The communication device may be used to realize the function of the session management function network element or the intermediate session management function network element in any of the above method embodiments. Wherein the session management function network element can be the SMF in Figure 4, or the source I-SMF in Figure 6, or the A-SMF in Figure 8, or the SMF among Figures 9 to 12; the intermediate session management function network element can Is the I-SMF in Figure 4, or the target I-SMF in Figure 6, or the target I-SMF in Figure 8, or the I-SMF in Figures 9 to 10, or the target in Figures 11 to 12 I-SMF. The communication device may be a network device, or a device capable of supporting the network device to implement the corresponding functions in the foregoing method embodiments (for example, a chip included in the network device), or the like.

Exemplarily, when the communication device executes an operation or step corresponding to a network element with a session management function in the method embodiment shown in FIG. The first information includes the information of the first multicast/broadcast service, and the communication device is used to control the PDU session anchor point of the protocol data unit PDU session associated with the terminal equipment and the first multicast/broadcast service; The second information of the session management function network element, the second information is used to indicate that the first tunnel has been established, and the first tunnel is used to transmit the second session between the intermediate user plane function network element and the multicast/broadcast user plane function network element. For the data of a multicast/broadcast service, the intermediate session management functional network element is used to control the intermediate user plane functional network element.

In a possible design, the transceiver module 1310 is also configured to receive multicast/broadcast capability information from the intermediate session management function network element, where the multicast/broadcast capability information is used to indicate whether the intermediate session management function network element supports group broadcast/broadcast; the processing module 1320 is configured to send the first information to the intermediate session management function network element through the transceiver module 1310 according to the multicast/broadcast capability information.

In a possible design, the processing module 1320 is further configured to send a first message to the PDU session anchor through the transceiver module 1310 according to the second information, where the first message is used to trigger the release of the PDU session anchor to transmit the first message. Data resource of multicast/broadcast service.

When the communication device executes the operations or steps corresponding to the intermediate session management function network element in the method embodiment shown in FIG. 4 , the transceiver module 1310 is configured to receive first information from the session management function network element, the first information Including the information of the first multicast/broadcast service, the session management function network element is used to control the PDU session anchor point of the protocol data unit PDU session associated with the terminal device and the first multicast/broadcast service; the processing module 1320 is used for according to the first multicast/broadcast service A piece of information, sending second information to the session management function network element through the transceiver module 1310, the second information is used to indicate that the first tunnel has been established, and the first tunnel is used to communicate between the intermediate user plane function network element and the multicast/broadcast user Data of the first multicast/broadcast service is transmitted between functional network elements on the user plane, and the communication device is used to control the functional network elements on the intermediate user plane.

In a possible design, the method further includes: the intermediate session management function network element sends the multicast/broadcast capability information of the intermediate session management function network element to the session management function network element, and the multicast/broadcast capability information is used to indicate Whether the NE with the intermediate session management function supports multicast/broadcast.

In a possible design, the processing module 1320 is further configured to send a second message to the intermediate user plane functional network element through the transceiver module 1310, and the second message is used to trigger the intermediate user plane functional network element to transmit the first multicast /Data configuration resources of the broadcast service.

The processing module 1320 involved in the communication device may be implemented by at least one processor or processor-related circuit components, and the transceiver module 1310 may be implemented by at least one transceiver or transceiver-related circuit components or a communication interface. The operation and/or function of each module in the communication device is to implement the corresponding flow of the method shown in FIG. 4 to FIG. 12 , and for the sake of brevity, details are not repeated here. Optionally, the communication device may further include a storage module, which may be used to store data and/or instructions, and the transceiver module 1310 and/or processing module 1320 may read the data and/or instructions in the access module, Thus, the communication device implements the corresponding method. The storage module can be implemented, for example, by at least one memory.

The above-mentioned storage module, processing module and transceiver module may exist separately, or may be integrated in whole or in part, such as integration of a storage module and a processing module, or integration of a processing module and a transceiver module.

Please refer to FIG. 14 , which is another schematic structural diagram of a communication device provided in an embodiment of the present application. The communication device may be used to implement the functions corresponding to the session management function network element or the intermediate session management function network element in the foregoing method embodiments. Wherein, the session management function network element can be the SMF in Figure 4, or the source I-SMF in Figure 6, or the A-SMF in Figure 8, or the SMF in Figures 9 to 12; the intermediate session management function network element It can be the I-SMF in Figure 4, or the target I-SMF in Figure 6, or the target I-SMF in Figure 8, or the I-SMF in Figures 9 to 10, or the I-SMF in Figures 11 to 12 Target I-SMF. The communication device may be a network device or a device capable of supporting the network device to implement the corresponding functions in the foregoing method embodiments (for example, a chip included in the network device), or the like.

The communication device 1400 may include a processor 1401 and a memory 1402 . Wherein, the memory 1402 is used to store program instructions and/or data, and the processor 1401 is used to execute the program instructions stored in the memory 1402, so as to implement the methods in the foregoing method embodiments.

Optionally, the memory 1402 is coupled to the processor 1401, and the coupling is an indirect coupling or a communication connection between devices, units or modules, which may be in electrical, mechanical or other forms, and is used between devices, units or modules information interaction.

Optionally, the communication device 1400 may further include a communication interface 1403, and the communication interface 1403 is used to communicate with other devices through a transmission medium, for example, to transmit received signals from other communication devices to the processor 1401, or from the processor The signal at 1401 is transmitted to other communication devices. The communication interface 1403 may be a transceiver, or an interface circuit, such as a transceiver circuit, a transceiver chip, and the like.

In one embodiment, the communication interface 1403 may be specifically configured to execute the actions of the transceiver module 1310 described above, and the processor 1401 may be specifically configured to execute the actions of the processing module 1320 described above, which will not be repeated herein.

The specific connection medium among the processor 1401, the memory 1402, and the communication interface 1403 is not limited in this embodiment of the present application. In the embodiment of the present application, in FIG. 14, the processor 1401, the memory 1402, and the communication interface 1403 are connected through the bus 1404. The bus is represented by a thick line in FIG. 14, and the connection between other components is only for schematic illustration. , is not limited. The bus can be divided into address bus, data bus, control bus and so on. For ease of representation, only one thick line is used in FIG. 14 , but it does not mean that there is only one bus or one type of bus.

The embodiment of the present application also provides a chip system, including: a processor, the processor is coupled with a memory, and the memory is used to store programs or instructions, and when the programs or instructions are executed by the processor, the The chip system implements the method corresponding to the session management function network element or the intermediate session management function network element in any of the above method embodiments.

Optionally, there may be one or more processors in the chip system. The processor can be realized by hardware or by software. When implemented in hardware, the processor may be a logic circuit, an integrated circuit, or the like. When implemented by software, the processor may be a general-purpose processor implemented by reading software codes stored in a memory.

Optionally, there may be one or more memories in the chip system. The memory can be integrated with the processor, or can be set separately from the processor, which is not limited in this application. Exemplarily, the memory can be a non-transitory processor, such as a read-only memory (read-only memory, ROM), which can be integrated with the processor on the same chip, or can be respectively arranged on different chips. The type of the memory, and the arrangement of the memory and the processor are not specifically limited.

Exemplarily, the chip system may be a field programmable gate array (field programmable gate array, FPGA), an application specific integrated circuit (ASIC), or a system on chip (SoC), It can also be a central processing unit (central processor unit, CPU), it can also be a network processor (network processor, NP), it can also be a digital signal processing circuit (digital signal processor, DSP), it can also be a microcontroller (micro controller unit, MCU), and can also be a programmable logic device (programmable logic device, PLD) or other integrated chips.

It should be understood that each step in the foregoing method embodiments may be implemented by an integrated logic circuit of hardware in a processor or instructions in the form of software. The method steps disclosed in connection with the embodiments of the present application may be directly implemented by a hardware processor, or implemented by a combination of hardware and software modules in the processor.

The embodiment of the present application also provides a computer-readable storage medium, where a computer program or instruction is stored in the computer storage medium, and when the computer program or instruction is executed, the communication device executes the method in any of the above method embodiments .

An embodiment of the present application further provides a computer program product, which enables the communication device to execute the method in any one of the above method embodiments when the communication device reads and executes the computer program product.

The embodiment of the present application also provides a communication system, which includes a session management function network element and an intermediate session management function network element. Optionally, the communication system may further include one or more of an anchor user plane functional network element, an intermediate user plane functional network element, a multicast/broadcast session management functional network element, and a multicast/broadcast user plane functional network element network element.

It should be understood that the processor mentioned in the embodiments of the present application may be a CPU, or other general-purpose processors, DSP, ASIC, FPGA or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, and the like. A general-purpose processor may be a microprocessor, or the processor may be any conventional processor, or the like.

It should also be understood that the memory mentioned in the embodiments of the present application may be a volatile memory or a nonvolatile memory, or may include both volatile and nonvolatile memories. Among them, the non-volatile memory can be ROM, programmable read-only memory (programmable ROM, PROM), erasable programmable read-only memory (erasable PROM, EPROM), electrically erasable programmable read-only memory (electrically EPROM) , EEPROM) or flash memory. Volatile memory can be random access memory (RAM), which acts as external cache memory. By way of illustration and not limitation, many forms of RAM are available such as static random access memory (static RAM, SRAM), dynamic random access memory (dynamic RAM, DRAM), synchronous dynamic random access memory (synchronous DRAM, SDRAM), double data rate synchronous dynamic random access memory (double data rate SDRAM, DDR SDRAM), enhanced synchronous dynamic random access memory (enhanced SDRAM, ESDRAM), synchronous connection dynamic random access memory (synchlink DRAM, SLDRAM ) and direct memory bus random access memory (direct rambus RAM, DR RAM).

It should be noted that when the processor is a general-purpose processor, DSP, ASIC, FPGA or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components, the memory (storage module) is integrated in the processor.

It should be noted that the memories described herein are intended to include, but are not limited to, these and any other suitable types of memories.

It should be understood that the various numbers involved in the various embodiments of the present application are only for the convenience of description, and the size of the serial numbers of the above-mentioned processes or steps does not mean the sequence of execution, the execution of each process or steps The order should be determined by its functions and internal logic, and should not constitute any limitation to the implementation process of the embodiment of the present invention.

Those skilled in the art can appreciate that the units and algorithm steps of the examples described in conjunction with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are executed by hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art may use different methods to implement the described functions for each specific application, but such implementation should not be regarded as exceeding the scope of the present application.

Those skilled in the art can clearly understand that for the convenience and brevity of the description, the specific working process of the above-described system, device and unit can refer to the corresponding process in the foregoing method embodiment, which will not be repeated here.

In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods may be implemented in other ways. For example, the device embodiments described above are only illustrative. For example, the division of the units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or May be integrated into another system, or some features may be ignored, or not implemented. In another point, the mutual coupling or direct coupling or communication connection shown or discussed may be through some interfaces, and the indirect coupling or communication connection of devices or units may be in electrical, mechanical or other forms.

The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or may be distributed to multiple network units. Part or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, each unit may exist separately physically, or two or more units may be integrated into one unit.

If the functions described above are realized in the form of software function units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art or the part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including Several instructions are used to make a computer device (which may be a personal computer, a server, or a network device, etc.) execute all or part of the steps of the methods described in the various embodiments of the present application. The aforementioned storage medium includes: various media capable of storing program codes such as U disk, mobile hard disk, ROM, RAM, magnetic disk or optical disk.

In each embodiment of the present application, if there is no special explanation and logical conflict, the terms and/or descriptions between different embodiments are consistent and can be referred to each other, and the technical features in different embodiments are based on their inherent Logical relationships can be combined to form new embodiments.

Claims

A multicast/broadcast session management method, characterized in that the method comprises:

The session management function network element sends the first information to the intermediate session management function network element, the first information includes the information of the first multicast/broadcast service, and the session management function network element is used to control the communication between the terminal equipment and the first The PDU session anchor point of the protocol data unit PDU session associated with the multicast/broadcast service;

The session management function network element receives second information from the intermediate session management function network element, the second information is used to indicate that the first tunnel has been established, and the first tunnel is used for the intermediate user plane function network element The data of the first multicast/broadcast service is transmitted between the multicast/broadcast user plane functional network element, and the intermediate session management functional network element is used to control the intermediate user plane functional network element.
The method according to claim 1, wherein the first tunnel is a direct tunnel between the intermediate user plane functional network element and the multicast/broadcast user plane functional network element.
The method according to claim 1 or 2, wherein the first information includes first indication information, and the first indication information is used to trigger the intermediate session management function network element to establish the first tunnel, Or the first indication information is used to query the intermediate session management function network element whether the first tunnel has been established.
The method according to any one of claims 1 to 3, wherein the second information includes information of the first multicast/broadcast service.
The method according to any one of claims 1 to 4, wherein the information of the first multicast/broadcast service includes one or more of the following information:

The identification information of the first multicast/broadcast service, the identification information of the area session of the first multicast broadcast service, the multicast/broadcast quality of service QoS information of the first multicast/broadcast service, or the Unicast QoS information corresponding to the multicast/broadcast QoS information of the first multicast broadcast service.
The method according to any one of claims 1 to 5, wherein the method further comprises:

The session management function network element receives multicast/broadcast capability information from the intermediate session management function network element, and the multicast/broadcast capability information is used to indicate whether the intermediate session management function network element supports multicast/broadcast ;

The session management function network element sends the first information to the intermediate session management function network element, including:

The session management function network element sends the first information to the intermediate session management function network element according to the multicast/broadcast capability information.
The method according to any one of claims 1 to 6, further comprising:

The session management function network element sends a first message to the PDU session anchor according to the second information, and the first message is used to trigger the release of the PDU session anchor to transmit the first multicast /broadcast service data resource.
A multicast/broadcast session management method, characterized in that the method comprises:

The intermediate session management function network element receives the first information from the session management function network element, the first information includes the information of the first multicast/broadcast service, and the session management function network element is used to control the communication between the terminal equipment and the first The PDU session anchor point of the protocol data unit PDU session associated with the multicast/broadcast service;

The intermediate session management function network element sends second information to the session management function network element according to the first information, and the second information is used to indicate that the first tunnel has been established, and the first tunnel is used in the The data of the first multicast/broadcast service is transmitted between the intermediate user plane functional network element and the multicast/broadcast user plane functional network element, and the intermediate session management functional network element is used to control the intermediate user plane functional network element .
The method according to claim 8, wherein the first tunnel is a direct tunnel between the intermediate user plane functional network element and the multicast/broadcast user plane functional network element.
The method according to claim 8 or 9, wherein the first information includes first indication information;

The method also includes:

The intermediate session management function network element establishes the first tunnel according to the first indication information, or queries whether the first tunnel has been established.
The method according to any one of claims 8 to 10, wherein the second information includes information of the first multicast/broadcast service.
The method according to any one of claims 8 to 11, wherein the information of the first multicast/broadcast service includes one or more of the following information:

The identification information of the first multicast/broadcast service, the identifier of the area session of the first multicast/broadcast service, the multicast/broadcast service quality QoS information of the first multicast/broadcast service, or the Unicast QoS information corresponding to the multicast broadcast QoS information of the first multicast/broadcast service.
The method according to any one of claims 8 to 12, further comprising:

The intermediate session management function network element sends the multicast/broadcast capability information of the intermediate session management function network element to the session management function network element, and the multicast/broadcast capability information is used to indicate the intermediate session management function Whether the NE supports multicast/broadcast.
The method according to any one of claims 8 to 13, further comprising:

The intermediate session management function network element sends a second message to the intermediate user plane function network element, and the second message is used to trigger the intermediate user plane function network element to transmit the first multicast/broadcast service Data configuration resources.
A communication device, characterized by comprising a module for performing the method according to any one of claims 1-7.
A communication device, characterized by comprising a module for performing the method according to any one of claims 8 to 14.
A communication device, characterized by comprising a processor and a memory, the processor is coupled to the memory, and the processor is used to control the device to implement the method according to any one of claims 1 to 7.
A communication device, characterized by comprising a processor and a memory, the processor is coupled to the memory, and the processor is used to control the device to implement the method according to any one of claims 8 to 14.
A computer-readable storage medium, which is characterized in that computer programs or instructions are stored in the storage medium, and when the computer programs or instructions are executed by a communication device, the implementation of claims 1 to 7, or 8 to 14 any one of the methods described.
A communication system, characterized by comprising the communication device according to claim 15 or 17, and the communication device according to claim 16 or 18.