CN115209354B

CN115209354B - Communication method and communication device

Info

Publication number: CN115209354B
Application number: CN202110387335.3A
Authority: CN
Inventors: 赵鹏涛; 李岩; 李濛
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2021-04-09
Filing date: 2021-04-09
Publication date: 2024-01-30
Anticipated expiration: 2041-04-09
Also published as: CN115209354A; WO2022213792A1

Abstract

The application provides a communication method and a communication device, wherein the communication method comprises the following steps: receiving first request information and an identifier of a first multicast group, wherein the first request information is used for requesting a terminal device to become a multicast source of the first multicast group, or the first request information is used for requesting the terminal device to join the first multicast group; sending second request information and an identifier of the first multicast group to a data management network element, wherein the second request information is used for requesting to acquire the identifier of the first session management network element, the first session management network element is used for multicast session management, and the first session management network element is associated with the identifier of the first multicast group; an identification of the first session management network element from the data management network element is received. According to the communication method, the multicast data transmission path from the UE directly to the first user plane function network element can be constructed, so that the detour of the transmission path is reduced, and the transmission delay of multicast communication is reduced.

Description

Communication method and communication device

Technical Field

The present application relates to the field of communications, and more particularly, to a communication method and a communication apparatus.

Background

In the field of computer networks or communications, hosts may communicate using a one-to-one group of multicast modes. Multicast is a group communication in which a multicast source can transmit data to a plurality of devices that need to be (join a group) at a time, while ensuring that communication of other devices that do not need to be (not join a group) is not affected.

However, in some scenarios, the multicast data needs to be forwarded through some network elements, so that a transmission path of the multicast is relatively roundabout, and the hop count is relatively high, which may result in relatively large transmission delay in the multicast communication process. It is therefore desirable to provide a technique that can solve the problem of a large transmission delay caused by path detour in the multicast communication process.

Disclosure of Invention

The communication method and the communication device can reduce the transmission delay in the multicast communication process.

In a first aspect, a communication method is provided, which may be performed by a session management network element, or may also be performed by a chip or a system of chips or a circuit configured in the session management network element, the method comprising: receiving first request information and an identifier of a first multicast group, wherein the first request information is used for requesting a terminal device to become a multicast source of the first multicast group, or the first request information is used for requesting the terminal device to join the first multicast group; sending second request information and an identifier of the first multicast group to a data management network element, wherein the second request information is used for requesting to acquire the identifier of the first session management network element, the first session management network element is used for multicast session management, and the first session management network element is associated with the identifier of the first multicast group; an identification of the first session management network element from the data management network element is received.

Therefore, according to the communication method of the embodiment of the application, the first session management network element for multicast session management is queried, so that the UE can construct a multicast data transmission path directly from the UE to the first user plane function network element when the session is established, the detour of the transmission path can be reduced, and the transmission delay is reduced.

Alternatively, the identification of the first multicast group may be a multicast address of the first multicast group.

As an example, the terminal device sends a second session establishment request message to the mobility management network element, where the second session establishment request message is used to request establishment of a second session between the terminal device and the data network, and the second session establishment request message includes the first request information and the identification of the first multicast group. The mobile management network element selects a second session management network element and sends a session management context request message to the second session management network element, wherein the session management context request message comprises the first request information and the identification of the first multicast group.

As yet another example, the terminal device sends a second session modification request message to the mobility management network element, where the second session modification request message is used to request modification of parameters of the second session, and the second session modification request message includes the first request information and the identification of the first multicast group. The mobile management network element sends a session management context update request message to the second session management network element, wherein the session management context update request message comprises the first request information and the identification of the first multicast group.

In another possible implementation, the second session management network element may also receive the first request information and the first multicast group identification from an application function network element.

It should be understood that the first request information and the first multicast group identifier may be carried in the same message, or may be carried in two messages that are sent continuously, which is not limited in this application.

Illustratively, the second session management network element determines, according to the first request information, that the terminal device requests to be a multicast source of the first multicast group, or the second request information is used to request the terminal device to join the first multicast group.

As an example, when the terminal device requests to become a multicast source of the first multicast group and the multicast data sent by the terminal device as the multicast source does not need to be analyzed by the application server, the second session management network element sends second request information and an identifier of the first multicast group to the data management network element, where the second request information is used to request to obtain an identifier of the first session management network element, the first session management network element is used to perform multicast session management, and the first session management network element is associated with the identifier of the first multicast group.

Optionally, before the second session management network element sends the second request information and the identifier of the first multicast group to the data management network element, the second session management network element sends third request information to the data management network element, where the third request information is used to request to verify that the terminal device becomes the authorization of the multicast source of the first multicast group. Correspondingly, after receiving the third request information, the data management network element verifies whether the terminal device has authorization to become a multicast source of the first multicast group. If the terminal device has authorization to become the multicast source of the first multicast group, the second session management network element continues to execute the subsequent procedure, otherwise, the second session management network element sends a response message to the terminal device, where the response message is used to reject the first request message, or is used to indicate that the terminal device fails to become the multicast source of the first multicast group, or the second session management network element ignores the first request message.

As yet another example, when the terminal device requests to join the first multicast group and the terminal device does not support accepting multicast data in a multicast manner, or the radio access network device in which the terminal device is located does not support multicast services, the second session management network element sends the second request information and the identification of the first multicast group to the data management network element.

Optionally, before the second session management network element sends the second request information and the identifier of the first multicast group to the data management network element, the second session management network element sends third request information to the data management network element, where the third request information is used to request to verify authorization of the terminal device to join the first multicast group. Correspondingly, after receiving the third request information, the data management network element verifies whether the terminal device has authorization to join the first multicast group. The second session management network element continues to perform subsequent flows in case the terminal device has authorization to join the first multicast group.

It should be understood that the second request information and the first multicast group identifier may be carried in the same message, or may be carried in two messages that are sent continuously, which is not limited in this application.

With reference to the first aspect, in certain implementations of the first aspect, the method further includes: the identity of the first session management network element is sent to the mobility management network element.

With reference to the first aspect, in certain implementation manners of the first aspect, before the sending the second request information and the first multicast group identifier to the data management network element, the method further includes: and sending third request information to the data management network element, wherein the third request information is used for requesting to verify that the terminal equipment is authorized to serve as a multicast source of the first multicast group under the condition that the first request information is used for requesting the terminal equipment to serve as a multicast source of the first multicast group, and requesting to verify that the terminal equipment is authorized to join the first multicast group under the condition that the first request information is used for requesting the terminal equipment to join the first multicast group.

Therefore, in the communication method of the embodiment of the application, the data management network element can store the authorization information of the multicast source of the terminal device as the first multicast group in advance or the authorization information of the terminal device joining the first multicast group, and the authorization condition of the terminal device is verified first before the terminal device requests to acquire the identifier of the first session management network element, so that the failure condition of the subsequent flow caused by the unauthorized terminal device can be avoided, and the reliability of communication is ensured.

With reference to the first aspect, in certain implementations of the first aspect, the method further includes: and sending first indication information and an identifier of the first session management network element to the terminal equipment, wherein the first session management network element is used for multicast session management, and the first indication information is used for indicating the terminal equipment to establish the first session.

Therefore, in the communication method of the embodiment of the application, the identifier of the first session management network element is sent to the terminal equipment, and the terminal equipment is instructed to establish the first session at the same time, so that the terminal equipment can establish a session through the first session management network element, the terminal equipment can construct a multicast data transmission path between the terminal equipment and the first user plane function network element, the detour of the transmission path can be reduced, and the transmission delay is reduced.

With reference to the first aspect, in certain implementations of the first aspect, the method further includes: and acquiring information of a first user plane functional network element, wherein the first user plane functional network element is used for forwarding multicast data, and the first user plane functional network element is associated with the first multicast group identifier.

With reference to the first aspect, in certain implementations of the first aspect, the method further includes: and constructing a data transmission path between the first user plane functional network element and the terminal equipment according to the information of the first user plane functional network element.

The information of the first user plane function network element is, for example, address information of the first user plane function network element or a data network access identifier (data network access identifier, DNAI) of the first user plane function network element.

Therefore, in the communication method provided by the embodiment of the application, after the session management network element acquires the information of the first user plane function network element, the data transmission path between the first user plane function network element and the terminal equipment is constructed, so that the multicast data can be directly transmitted from the terminal equipment to the first user plane function network element or directly transmitted from the first user plane function network element to the terminal equipment, thereby reducing the detour of the multicast data transmission path and reducing the transmission delay.

With reference to the first aspect, in some implementations of the first aspect, the acquiring information of the first user plane function network element includes: sending fourth request information and an identifier of the first multicast group to the data management network element, wherein the fourth request information is used for requesting to acquire the information of the first user plane function network element; receiving information of the first user plane function network element from the data management network element; or sending the fourth request information and the identification of the first multicast group to the first session management network element; information of the first user plane function network element from the first session management network element is received.

Further, after receiving the information of the first user plane function network element, the session management network element uses the first user plane function network element as an additional session anchor point session management network element of the first session, inserts a second user plane function network element in the user plane according to the information of the first user plane function network element, or selects the existing second user plane function network element, and performs corresponding configuration through the N4 session, so that the second user plane function network element has the function of UL CL or BP.

Therefore, the communication method of the embodiment of the application selects the first user plane function network element corresponding to the first multicast group identifier as the additional session anchor user plane function network element,

the distribution of the multicast data of the terminal equipment to the first user plane functional network element is realized by using the inserted second user plane functional network element or the selected second user plane functional network element as the UL CL/BP, so that the transmission path of the multicast data from the multicast source terminal equipment to the first user plane functional network element is constructed, the detour of the transmission path can be reduced, and the transmission delay is reduced.

With reference to the first aspect, in certain implementation manners of the first aspect, the receiving the first request information and the identification of the first multicast group includes: receiving the first request information and the identification of the first multicast group from the terminal equipment; or receiving the first request information from the application function network element and the identification of the first multicast group.

In a second aspect, a communication method is provided, which may be performed by a mobility management network element or by a chip or a system of chips or a circuit arranged in the mobility management network element, the method comprising: receiving a first session establishment request message from a terminal device, wherein the first session establishment request message is used for requesting to establish a first session between the terminal device and a data network, the first session establishment request message comprises an identifier of a first session management network element, and the first session management network element is used for multicast session management; and sending first request information and an identifier of a first multicast group to the first session management network element, wherein the first request information is used for requesting the terminal equipment to become a multicast source of the first multicast group, or the first request information is used for requesting the terminal equipment to join the first multicast group.

Therefore, according to the communication method of the embodiment of the application, the first session management network element for multicast session management is selected to establish the session, so that a multicast data transmission path from the UE directly to the first user plane function network element can be constructed, the detour of the transmission path can be reduced, and the transmission delay is reduced.

With reference to the second aspect, in certain implementations of the second aspect, before the receiving the first session establishment request message from the terminal device, the method further includes: receiving the first request information and the identification of the first multicast group from the terminal equipment; and sending the first request information and the identification of the first multicast group to a second session management network element.

With reference to the second aspect, in some implementations of the second aspect, the receiving the first request information from the terminal device and the identification of the first multicast group includes: receiving a second session establishment request message from the terminal device, wherein the second session establishment request message comprises the first request information and the identification of the first multicast group; or receiving a second session modification request message from the terminal device, the second session modification request message comprising the first request information and an identification of the first multicast group.

In a third aspect, a communication method is provided, which may be performed by a terminal device or by a component (e.g. a chip or a circuit) arranged in the terminal device, the method comprising: receiving first indication information from a second session management network element and an identifier of the first session management network element, wherein the first session management network element is used for multicast session management, and the first indication information is used for indicating the terminal equipment to establish a first session; and sending a first session establishment request message to the mobile management network element, wherein the first session establishment request message is used for requesting to establish the first session between the terminal equipment and the data network, the first session establishment request message comprises an identifier of the first session management network element, and the first session management network element is used for multicast session management.

Therefore, the communication method of the embodiment of the application can construct the multicast data transmission path from the UE directly to the first user plane functional network element, reduce the detour of the transmission path and reduce the transmission delay.

With reference to the third aspect, in some implementations of the third aspect, before the sending of the session establishment request message to the mobility management network element, the method further includes: and sending first request information and a first multicast group identifier to the mobile management network element, wherein the first request information is used for requesting the terminal equipment to become a multicast source of the first multicast group, or the first request information is used for requesting the terminal equipment to join the first multicast group.

With reference to the third aspect, in some implementations of the third aspect, the sending the first request information and the first multicast group identifier to the mobility management network element includes: sending a second session establishment request message to the mobility management network element, wherein the second session establishment request message comprises the first request information and the identifier of the first multicast group; or sending a second session modification request message to the mobility management network element, wherein the second session modification request message comprises the first request information and the identification of the first multicast group.

In a fourth aspect, there is provided a communication apparatus comprising: the receiving and transmitting module is used for receiving first request information and an identifier of a first multicast group, wherein the first request information is used for requesting the terminal equipment to become a multicast source of the first multicast group or requesting the terminal equipment to join the first multicast group; the transceiver module is further configured to send second request information and an identifier of the first multicast group to a data management network element, where the second request information is used to request to obtain an identifier of a first session management network element, the first session management network element is used to perform multicast session management, and the first session management network element is associated with the identifier of the first multicast group; the transceiver module is further configured to receive an identification of the first session management network element from the data management network element.

The transceiver module may perform the processing of receiving and transmitting in the foregoing first aspect; the communication device may further comprise a processing module which may perform other processing than reception and transmission in the aforementioned first aspect.

In a fifth aspect, there is provided a communication apparatus comprising: a transceiver module, configured to receive a first session establishment request message from a terminal device, where the first session establishment request message is used to request establishment of a first session between the terminal device and a data network, the first session establishment request message includes an identifier of a first session management network element, and the first session management network element is used to perform multicast session management; the transceiver module is further configured to send first request information and an identifier of a first multicast group to the first session management network element, where the first request information is used to request the terminal device to become a multicast source of the first multicast group, or the first request information is used to request the terminal device to join the first multicast group.

The transceiver module may perform the processing of reception and transmission in the foregoing second aspect; the communication device may further comprise a processing module that may perform other processing than reception and transmission in the aforementioned second aspect.

In a sixth aspect, there is provided a communication apparatus comprising: the receiving and transmitting module is used for receiving first indication information from the second session management network element and the identification of the first session management network element, wherein the first session management network element is used for multicast session management, and the first indication information is used for indicating the terminal equipment to establish a first session; the transceiver module is further configured to send a first session establishment request message to a mobility management network element, where the first session establishment request message is used to request establishment of the first session between the terminal device and the data network, the first session establishment request message includes an identifier of the first session management network element, and the first session management network element is used to perform multicast session management.

The transceiver module may perform the processing of reception and transmission in the foregoing third aspect; the communication device may further include a processing module that may perform other processing than reception and transmission in the foregoing third aspect.

In a seventh aspect, there is provided a communication apparatus comprising: a processor for executing a computer program stored in a memory to cause the communication device to perform any one of the possible implementations of the first or second aspect.

In an eighth aspect, there is provided a computer readable storage medium having stored thereon a computer program which, when run on a computer, causes the computer to perform any one of the possible implementations of the first to third aspects.

In a ninth aspect, there is provided a computer program product comprising computer program instructions which, when run on a computer, cause the computer to perform any one of the possible implementations of the first to third aspects.

In a tenth aspect, there is provided a chip system comprising: a processor for calling and running a computer program from a memory, such that a communication device on which the chip system is installed performs any one of the possible implementations of the first to third aspects.

Drawings

Fig. 1 is a schematic diagram of a network architecture suitable for use in the method provided in the embodiments of the present application.

Fig. 2 is a schematic diagram of another network architecture suitable for use in the method provided in the embodiments of the present application.

Fig. 3 is a schematic diagram of a system architecture for multicast communications.

Fig. 4 is a schematic diagram of another system architecture for multicast communications.

Fig. 5 is a schematic flow chart of a communication method provided in one embodiment of the present application.

Fig. 6 is a schematic flow chart of a communication method according to another embodiment of the present application.

Fig. 7 is a schematic flow chart of a communication method according to yet another embodiment of the present application.

Fig. 8 is a schematic diagram of a system architecture for multicast communication according to an embodiment of the present application.

Fig. 9 is a schematic flow chart of a communication method provided in yet another embodiment of the present application.

Fig. 10 is a schematic diagram of another system architecture for multicast communication according to an embodiment of the present application.

Fig. 11 is a schematic flow chart of a communication method provided in yet another embodiment of the present application.

Fig. 12 is a schematic flow chart of a communication method according to yet another embodiment of the present application.

Fig. 13 is a schematic diagram of a system architecture for multicast communication according to an embodiment of the present application.

Fig. 14 is a schematic flow chart of a communication method provided in yet another embodiment of the present application.

Fig. 15 is a schematic diagram of a system architecture for multicast communication according to an embodiment of the present application.

Fig. 16 is a schematic block diagram of a communication device provided in one embodiment of the present application.

Fig. 17 is a schematic block diagram of a communication apparatus provided in another embodiment of the present application.

Fig. 18 is a schematic block diagram of a communication apparatus provided in accordance with yet another embodiment of the present application.

Fig. 19 is a schematic block diagram of a communication apparatus provided in yet another embodiment of the present application.

Detailed Description

The technical solutions in the present application will be described below with reference to the accompanying drawings.

The technical scheme provided by the application can be applied to various communication systems, such as: long term evolution (long term evolution, LTE) systems, LTE frequency division duplex (frequency division duplex, FDD) systems, LTE time division duplex (time division duplex, TDD), universal mobile telecommunications system (universal mobile telecommunication system, UMTS), worldwide interoperability for microwave access (worldwide interoperability for microwave access, wiMAX) telecommunications systems, fifth generation (5th generation,5G) systems or New Radio (NR), and the like.

The network element naming may be different in different network systems. The present application will be described below with reference to the naming of network elements in a 5G network.

Fig. 1 and 2 are schematic diagrams of network architectures suitable for use in the methods provided in embodiments of the present application. Fig. 1 is a schematic diagram of a 5G network architecture based on a servitization interface, and fig. 2 is a schematic diagram of a 5G network architecture based on a point-to-point interface. The main network elements involved in the 5G network system will be briefly described with reference to the schematic diagrams of the 5G network architecture shown in fig. 1 and 2.

1. User Equipment (UE): may include various handheld devices, vehicle mount devices, wearable devices, computing devices, or other processing devices connected to a wireless modem, as well as various forms of terminals, mobile Stations (MSs), terminals, soft terminals, etc. Such as water meters, electricity meters, sensors, etc.

2. Radio access network (radio access network, RAN) network element: hereinafter abbreviated as RAN, corresponds to the access network device.

The system is used for providing network access functions for authorized user equipment in a specific area and can use transmission tunnels with different qualities according to the level of the user equipment, the service requirements and the like.

The RAN network element can manage radio resources, provide access service for the ue, and further complete forwarding of control signals and ue data between the ue and the core network, and may also be understood as a base station in a conventional network. For example, the RAN may be an NB, eNB, gNB, ng-eNB, or any other access network device.

3. User plane function (user plane function, UPF): quality of service (quality of service, qoS) handling for packet routing and forwarding, user plane data, etc.

In a 5G communication system, the user plane network element may be a user plane function (user plane function, UPF) network element. In future communication systems, the user plane network element may still be a UPF network element, or may have other names, which is not limited in this application.

4. Data Network (DN): for providing a network for transmitting data.

In a 5G communication system, the data network element may be a data network element. In future communication systems, the data network element may still be a DN network element, or may have other names, which are not limited in this application.

5. AMF: the method is mainly used for mobility management, access management and the like, and can be used for realizing other functions besides session management, such as legal interception, access authorization/authentication and the like, in MME functions.

In a 5G communication system, the access and mobility management network element may be an access and mobility management function (access and mobility management function, AMF). In future communication systems, the access and mobility management device may still be an AMF, or may have other names, which are not limited in this application.

6. Session management function (session management function, SMF): the method is mainly used for session management, network interconnection protocol (internet protocol, IP) address allocation and management of user equipment, terminal node of selecting manageable user plane functions, strategy control and charging function interfaces, downlink data notification and the like.

In a 5G communication system, the session management network element may be a session management function network element. In future communication systems, the session management network element may still be an SMF network element, or may have other names, which are not limited in this application.

7. Policy control function (policy control function, PCF): a unified policy framework for guiding network behavior, providing policy rule information for control plane function network elements (e.g., AMFs, SMFs, etc.), and the like.

In a 4G communication system, the policy control network element may be a policy and charging rules function (policy and charging rules function, PCRF) network element. In a 5G communication system, the policy control network element may be a policy control function PCF network element. In future communication systems, the policy control network element may still be a PCF network element, or may have other names, which are not limited in this application.

8. Application function (application function, AF): the method is used for carrying out data routing of application influence, a wireless access network open function network element, strategy control by interaction with a strategy framework and the like.

In a 5G communication system, the application network element may be an application function network element. In future communication systems, the application network element may still be an AF network element, or may have other names, which are not limited in this application.

9. Unified data management (unified data management, UDM): for handling UE identities, access authentication, registration, mobility management, etc.

In the 5G communication system, the data management network element may be a unified data management network element; in the 4G communication system, the data management network element may be a home subscriber server (home subscriber server, HSS) network element, and in the future communication system, the unified data management may still be a UDM network element, or may also have other names, which is not limited in this application.

10. Unified data store (unified data repository, UDR): mainly comprises the following functions: access function of subscription data, policy data, application data and other types of data.

11. Authentication server (authentication server function, AUSF): the method is used for realizing the bidirectional authentication of the user equipment by the authentication service and the generation of the secret key, and supports a unified authentication framework.

In a 5G communication system, the authentication server may be an authentication server function network element. In future communication systems, the authentication server function network element may still be an AUSF network element, or may have other names, which is not limited in this application.

It will be appreciated that the network elements or functions described above may be either network elements in a hardware device, software functions running on dedicated hardware, or virtualized functions instantiated on a platform (e.g., a cloud platform). For convenience of explanation, the network device is taken as an access and mobility management network element AMF, and the base station is taken as a radio access network RAN for explanation.

In the network architecture shown in fig. 2, the user equipment is connected to the AMF through an N1 interface, the RAN is connected to the AMF through an N2 interface, and the RAN is connected to the UPF through an N3 interface. The UPFs are connected through an N9 interface, and are interconnected through an N6 interface DN. The SMF controls the UPF through the N4 interface. The AMF interfaces with the SMF through an N11 interface. The AMF acquires the user equipment subscription data from the UDM unit through an N8 interface, and the SMF acquires the user equipment subscription data from the UDM unit through an N10 interface.

It should be understood that the network architecture applied to the embodiments of the present application is merely illustrative, and the network architecture to which the embodiments of the present application are applied is not limited to this, and any network architecture capable of implementing the functions of the respective network elements described above is applicable to the embodiments of the present application.

For example, in some network architectures, network function network element entities such as AMF, SMF, PCF, BSF, and UDM are all called Network Function (NF) network elements; alternatively, in other network architectures, the set of AMF, SMF, PCF, BSF, UDM, etc. network elements may be referred to as control plane function network elements.

For ease of understanding the embodiments of the present application, some concepts or terms involved in the present application will first be briefly described.

1. Unicast of

And in a one-to-one communication mode between hosts, switches and routers in the network only forward data and do not copy the data. If 10 clients need the same data, the server needs to transmit one by one, repeating the same work 10 times. But because it can respond in time to the requirements of each client, current web browsing all adopts unicast mode, i.e. IP unicast protocol. Routers and switches in the network select transmission paths according to their destination addresses to deliver IP unicast data to their designated destinations. The unicast IP address is the IP address of a single host.

2. Multicast

A one-to-one group of communication modes between hosts, i.e. hosts joining the same group can accept all data in the group, and switches and routers in the network only copy and forward their required data to the on-demand subscribers. Hosts may request to a router to join or leave a group, and routers and switches in the network selectively replicate and transfer data, i.e., transfer intra-group data only to those hosts joining the group. This allows data to be transferred to multiple hosts that are in need (joining a group) at a time, while ensuring that other communications are not affected by other hosts that are not in need (joining a group). The multicast IP address is a class D IP address, ranging from: 224.0.0 to 239.255.255.255.

A multicast group is a collection of receivers identified by IP multicast addresses.

The host receives multicast data addressed to a certain multicast group by joining the multicast group as a member of the multicast group. The members of the multicast group are dynamic and hosts can access or leave the multicast group at any time. Multicast group members may be widely distributed anywhere in the network.

The host sending information to the multicast group is the multicast source. The multicast source generally does not need to join a multicast group, and one multicast source can send information to multiple multicast groups at the same time, and multiple multicast sources can also send information to one multicast group at the same time.

3. Broadcasting

The network performs unconditional copying and forwarding on the signals sent by each host computer, and all the hosts can receive all the information (whether you need or not) because of no path selection, so the network cost is low. Cable television networks are typically broadcast networks, in which our television set actually receives signals from all channels, but only restores the signal from one channel to a picture. The presence of broadcast is also allowed in data networks, but is typically limited to local area networks of two-layer switches, prohibiting broadcast data from passing through routers, preventing broadcast data from affecting large-area hosts. There are four broadcast IP addresses, the limited broadcast address, 255.255.255.255; broadcast address pointing to network, i.e. address with host number of all 1; broadcast addresses pointing to the subnet, i.e. addresses with host numbers of all 1 and specific subnet numbers; broadcast to all subnets requires knowledge of the subnet mask of the destination network, and the subnet number and host number are all 1.

4. Protocol data unit (protocol data unit, PDU) session

The 5G core network (5G core, 5 GC) supports PDU connectivity services. The PDU connection service may refer to a service of exchanging PDU packets between the terminal device and the DN. The PDU connection service is implemented by the terminal device initiating the establishment of a PDU session. After a PDU session is established, a data transmission channel between the terminal and the DN is established. In other words, the PDU session is UE level. Each terminal device may establish one or more PDU sessions. The terminal device may access the DN through a PDU session established between the terminal device and the DN.

As previously mentioned, the SMF primary user is responsible for session management in the mobile network. The PDU session can be established, modified or released between the terminal device and the SMF through NAS session management (session management, SM) signaling.

In the embodiment of the present application, the terminal device may establish multiple PDU sessions or multiple PDU connection services, for example, the terminal device may establish two or more PDU sessions, and the multiple PDU sessions are not limited. For example, the DN identities (data network name, DNN) of these PDU sessions may be different or the same. As another example, different PDU sessions may be served by the same SMF or may be served by different SMFs. As another example, the establishment of these PDU sessions may be initiated simultaneously or sequentially.

5. Arbitrary Source Multicast (ASM)

In the ASM model, any sender may become a multicast source and send information to a multicast address. The receiver can join or leave the multicast group at any time, but cannot know the address of the multicast source in advance.

6. Source multicast (source-specific multicast, SSM)

In SSM model, the receiver can know the address of the multicast source in advance, and the source can be specified at the client. SSM establishes a dedicated multicast forwarding path directly between the receiver and its designated multicast source using a different multicast address range than ASM.

7. Multicast/broadcast session management function (multicast/broadcast-session management function, MB-SMF)

The MB-SMF is mainly responsible for multicast broadcast session management, controls multicast broadcast transmission, and carries out corresponding configuration on the MB-UPF and the RAN according to policy rules provided by PCF or locally configured multicast broadcast service so as to complete the transmission of multicast broadcast streams.

8. Multicast/broadcast user plane function (multicast/broadcast-user plane function, MB-UPF)

The MB-UPF is mainly responsible for transmitting the multicast broadcast stream to the RAN (or UPF), and may perform packet filtering and distribution of the multicast broadcast stream, to implement QoS enhancement, counting/reporting, and the like of the multicast broadcast service.

9. Uplink classifier (uplink classifier, UL CL)/Branching Point (BP)

Both UL CL and BP are UPF functions, and the UL CL functions as an upstream classifier for the data flow, i.e. to offload data to a local DN or remote protocol data unit session anchor (PDU session anchor, PSA) UPF based on the identification of upstream characteristics of the traffic flow. Meanwhile, UL CL performs aggregation processing on the downstream. BP works the same as UL CL, which is an upstream classifier for internet protocol version four (internet protocol version, IPv 4), except BP is a split point for internet protocol version six (internet protocol version, IPv 6).

In order to facilitate understanding of the communication method provided in the embodiments of the present application, two schemes of multicast communication in a 5G network are briefly described below with reference to fig. 3 to 4.

In the scheme shown in fig. 3, UE1, UE2, UE3 are members of a multicast group, UE4 is a multicast source of the multicast group, and an application server (application server, AS) is an anchor point for data processing and forwarding, i.e. an uplink of the UE for transmitting multicast data must reach the AS, the AS processes (e.g. parses or simply forwards data) the data, and then the AS performs transmission of downlink multicast data. AS can be seen from fig. 3, UE4 sends multicast data to the multicast group AS a multicast source, sends the multicast data to AS via unicast PSA UPF, AS processes the multicast data, forwards the multicast data to MB-UPF, and MB-UPF sends the multicast data to RAN via N3 multicast tunnel, and RAN further sends the multicast data to multicast members UE1, UE2 and UE 3.

However, if the AS does not need to analyze the multicast data transmitted by the UE4, that is, if the AS only needs to forward the multicast data, there is a case where the path detouring and the number of hops are large in the multicast communication through the transmission path shown in fig. 3, and the transmission delay increases.

In the scheme shown in fig. 4, UE1, UE2, and UE3 are multicast group members, and when UE1 and UE2 support multicast data reception in a multicast manner, RAN1 where UE1 and UE2 are located also supports multicast service, but UE3 does not support multicast data reception in a multicast manner, or RAN 2 where UE3 is located does not support multicast service, the multicast data needs to be sent to UE3 in a unicast manner. After receiving the multicast data (which may be sent by the UE or AS at this time), the MB-UPF forwards the multicast data to the RAN1 through the shared multicast tunnel, and the RAN1 sends the multicast data to the UE1 and the UE2 through a point-to-multipoint (PTM) or point-to-point (PTP) manner; the multicast data is forwarded to the PSA UPF of the unicast session of UE3 through the forwarding tunnel, the PSA UPF sends the multicast data to RAN 2 through unicast mode, and RAN 2 sends the multicast data to UE3 through PTP mode.

However, for the path of forwarding the multicast packet to the multicast member by the MB-UPF, when the MB-UPF can be directly connected to the RAN 2 or the position of the PSA UPF is higher from the RAN 2 than the MB-UPF, the forwarding path from the MB-UPF to the PSA UPF to the RAN 2 is detoured or the number of hops is large, thereby increasing the transmission delay.

According to the schemes shown in fig. 3 and fig. 4, how to solve the disadvantage of large transmission delay caused by path detour in the multicast communication process is a problem that we need to consider.

Fig. 5 is a schematic flow chart of a method 500 provided by an embodiment of the present application. As can be seen in fig. 5, the method 500 includes:

s510, the second session management network element receives the first request information from the terminal device and the identification of the first multicast group.

The first request information is used for requesting the terminal device to become a multicast source of the first multicast group, or the first request information is used for requesting the terminal device to join the first multicast group. The identification of the first multicast group may be, for example, a multicast address of the first multicast group.

S520, the second session management network element sends the second request information and the identification of the first multicast group to the data management network element.

S530, the data management network element sends the identification of the first session management network element to the second session management network element.

Illustratively, the data management network element determines a first session management network element corresponding to the first multicast group identifier according to the first multicast group identifier, and then sends the identifier of the first session management network element to the second session management network element.

Optionally, in one possible implementation manner, the second session management network element obtains information of a first user plane function network element, where the first user plane function network element is used for multicast data management, and the first user plane function network element is associated with a first multicast group identifier. The information of the first user plane function network element is, for example, an ID of the first user plane function network element or DNAI of the first user plane function network element.

As an example, the second session management network element obtains information of the first user plane function network element through the first session management network element. Specifically, the second session management network element sends fourth request information and an identifier of the first multicast group to the first session management network element, where the fourth request information is used to request to obtain information of the first user plane function network element. The first session management network element determines the information of the first user plane function network element according to the identification of the first multicast group, and sends the information of the first user plane function network element to the second session management network element.

As yet another example, the second session management network element obtains information of the first user plane function network element through the data management network element. Specifically, the second session functional network element sends fourth request information and the identification of the first multicast group to the data management network element. The data management network element determines the information of the first user plane function network element according to the identification of the first multicast group, and sends the information of the first user plane function network element to the second session management network element. It should be appreciated that in the solution provided in this example, the first session management network element stores information of the first user plane function network element in the data management network element during the first multicast configuration procedure.

S540, the second session management network element sends the first indication information and the identification of the first session management network element to the terminal equipment.

The second session management network element sends the first indication information and the identifier of the first session management network element to the mobile management network element after obtaining the identifier of the first session management network element from the data management network element, where the first indication information is used to instruct the terminal device to establish the first session, and the mobile management network element transparently transmits the first indication information and the identifier of the first session management network element to the terminal device.

S550, the terminal device sends a first session establishment request message to the mobility management network element.

The terminal device sends a first session establishment request message to the mobility management element according to the first indication information, where the first session establishment request message is used to request establishment of a first session between the terminal device and the data network, and the first session establishment request message includes an identifier of the first session management element.

S560, the mobile management network element sends the first request information and the identification of the first multicast group to the first session management network element.

Illustratively, after receiving the first session establishment request message, the mobility management element obtains the identity of the first session management element, and then selects the first session management element to establish the first session. The mobile management network element sends the first request information and the identification of the first multicast group to the first session management network element to indicate the terminal equipment to request to become a multicast source of the first multicast group or request to join the first multicast group.

It should be understood that the session management network element in this embodiment is a network element for performing session management, the data management network element in this embodiment is a network element for performing access functions on various types of data, the first session management network element in this embodiment is a network element for performing multicast session management associated with the identification of the first multicast group, the mobility management network element in this embodiment is a network element for mobility management and access management, and names of network elements for performing similar functions in different systems may be different. For example, in a 5G system, the session management network element may be an SMF, the data management network element may be a UDR, the first session management network element may be an MB-SMF corresponding to the first multicast group, and the mobility management network element may be an AMF.

Therefore, the communication method of the embodiment of the application can construct the multicast data transmission path from the UE directly to the multicast session management network element, reduce the detour of the transmission path and reduce the transmission delay.

Fig. 6 is a schematic flow chart of a method 600 provided by an embodiment of the present application. In the embodiment shown in fig. 6, the UE requests the multicast source AS the first multicast group, and the multicast data sent by the UE AS the multicast source does not need AS parsing. As can be seen in fig. 6, method 600 includes:

s601, completing the first multicast group configuration between the network equipment and the UE.

S602, the UE sends a first PDU session establishment request message to the AMF.

Illustratively, the UE sends a first PDU session establishment request message to the AMF via the RAN, the first PDU session establishment request message requesting establishment of a first PDU session between the UE and the data network DN. The first PDU session establishment request message includes a first multicast group identifier and first request information, where the first multicast group identifier is used to identify a first multicast group, and the first multicast group identifier may be, for example, a multicast address of the first multicast group, and the first request information is used to request a multicast source serving as the first multicast group.

It should be understood that the first request information may also be used to request the network device to forward the multicast data sent by the UE. It should also be understood that the first request information and the multicast group identification may also be sent in other messages, which is not limited in this application.

S603, AMF selects SMF.

Illustratively, after the AMF receives the first PDU session establishment request message from the UE, the SMF is selected to establish the first PDU session.

S604, the AMF sends a session management context request message to the SMF.

Illustratively, the AMF transmits a session management context request message for requesting establishment of the first PDU session management context to the SMF selected in S603. Optionally, the session management context request message includes first request information and a first multicast group identification.

S605, the SMF sends a session management context response message to the AMF.

Illustratively, after receiving the session management context request message sent by the AMF, the SMF creates a session management context for the first PDU session, and then sends a session management context response message to the AMF, where the session management context response message indicates that session management context establishment for the first PDU session is complete.

S606, the SMF checks the authorization of the UE as a multicast source and acquires the MB-SMF ID.

Illustratively, the SMF determines the type of the first multicast group based on the first multicast group identification. It should be appreciated that the types of multicast groups include ASM mode and SSM model. When the type of the first multicast group is ASM mode, the SMF checks the authorization of the UE as a multicast source. For example, the SMF obtains authorization information of the multicast source of the first multicast group from the UDR, and determines whether the UE is authorized as the multicast source according to the authorization information.

When the UE has authorization as a multicast source of the first multicast group, the SMF obtains an identity of the MB-SMF, e.g. an MB-SMF ID, from the UDR according to the first multicast group identity.

S607, the SMF transmits a first message to the UE, the first message including the first information, the second information, and the MB-SMF ID.

Illustratively, when the UE has authorization as a multicast source of the first multicast group, the SMF sends first information for rejecting the first PDU session establishment request message, second information for instructing the UE to reestablish the PDU session, and the MB-SMF ID to the UE through the first message.

It should be understood that the first information, the second information, and the MB-SMF ID may also be carried in different messages, which is not limited in this application. In one possible implementation, the SMF invokes the namf_n1n2messagetransfer service of the AMF to send the first message to the UE, the AMF passes the first message to the RAN through N2 PDU Session Request, and the RAN passes the first message through AN-specific resource setup procedure to the UE.

S608, the UE sends a second PDU session establishment request message to the AMF.

The UE may send a second PDU session establishment request message to the AMF according to the second information, the second PDU session establishment request message requesting establishment of a second PDU session. The second PDU session establishment request message includes the MB-SMF ID. Optionally, the second PDU session establishment request message further includes first request information and a first multicast group identifier, where the first request information is used to request a multicast source that is the first multicast group.

S609, AMF selects MB-SMF.

Illustratively, the AMF receives a second PDU session establishment request message from the UE, and obtains the MB-SMF ID carried in the second PDU session establishment request message, and the AMF selects the MB-SMF to establish the second PDU session according to the MB-SMF ID.

S610, the AMF sends a session management context request message to the MB-SMF.

Illustratively, the AMF sends a session management context request message to the MB-SMF requesting establishment of the second PDU session management context. The session management context request message includes first request information and a first multicast group identification.

As another possible implementation, in S607, the SMF sends the AMF a first correspondence of the MB-SMF ID, the first request information, and the first PDU session ID. Correspondingly, the AMF receives the first correspondence from the SMF and stores the first correspondence locally. In S608, the second PDU session ID and the first PDU session ID are included in the second PDU session establishment request message transmitted by the UE to the AMF. Correspondingly, the AMF receives a second PDU session establishment request message from the UE, acquires a second PDU session ID and a first PDU session ID, determines an MB-SMF ID and first request information according to the first PDU session ID and a first correspondence, selects a corresponding MB-SMF as a session management network element of the second PDU session according to the MB-SMF ID, and carries first request information corresponding to the first PDU session in a session management context request message of S610.

S611, the network side selects MB-UPF to complete the second PDU session establishment flow.

Illustratively, after receiving a session management context request message sent by the AMF, the MB-SMF obtains first request information and a first multicast group identifier in the session management context request message, and determines, according to the first request information, that the UE requests to be a multicast source of the first multicast group. The MB-SMF finds the MB-UPF from the corresponding first multicast context according to the first multicast group identification, and selects the MB-UPF as the PSA UPF for the second PDU session. The specific manner in which the network side continues to complete the establishment of the second PDU session is not limited.

Therefore, in the communication method provided by the embodiment of the application, in the PDU session establishment flow, by directly selecting the MB-UPF of the multicast group corresponding to the multicast source UE as the PSA UPF of the new session of the multicast source UE, the transmission path of the multicast data from the multicast source UE to the MB-UPF is constructed, thereby reducing the detour of the transmission path and reducing the transmission delay.

Fig. 7 is a schematic flow chart of a method 700 provided by an embodiment of the present application. In the embodiment shown in fig. 7, the UE requests the multicast source AS the first multicast group, and the multicast data sent by the UE AS the multicast source does not need AS parsing. As can be seen in fig. 7, method 700 includes:

And S701, completing the configuration of the first multicast group between the network equipment and the UE.

S702, the UE sends a first PDU session modification request message to the AMF, where the first PDU session modification request message is used to request modification of a quality of service (quality of service, qoS) parameter of the first PDU session, and the first PDU session modification request message includes first request information and a first multicast group identifier, where the first multicast group identifier is used to identify a first multicast group, and the first multicast group identifier may be, for example, a multicast address of the first multicast group, where the first request information is used to request the UE to serve as a multicast source of the first multicast group.

S703, the AMF sends a session management context update request message to the SMF, where the session management context update request message includes the first request information and the first multicast group identifier.

In another possible implementation, the first request information and the first multicast group identification may also be sent by the AF to the SMF. For example, in S704, the AF sends a second message to the SMF, where the second message includes the first request information and the first multicast group identification. The second message may be, for example, a request message by the UE as a multicast source. It will be appreciated that the AF may send the second message directly to the SMF or may forward it via a network opening function (network exposure function, NEF).

S705, the SMF checks the authorization of the UE as a multicast source and acquires the MB-SMF ID.

It should be understood that S705 is similar to S606 in method 600, and the description is not repeated here.

S706, the SMF sends a first message to the UE, where the first message includes the second information and the MB-SMF ID.

Illustratively, when the UE has authorization as a multicast source for the first multicast group, the SMF sends second information and the MB-SMF ID to the UE through a first message, wherein the second information is used to instruct the UE to reestablish the PDU session.

As a specific example, the SMF invokes the namf_n1n2messagetransfer service of the AMF to send a first message to the UE, the first message including the second information and the MB-SMF ID, the AMF sending the first message to the UE via the RAN. It should be appreciated that in some implementations, the first message may also be a PDU session modification command message.

S707, the UE sends a second PDU session establishment request message to the AMF.

S708, the AMF selects MB-SMF.

S709, the AMF sends a session management context request message to the MB-SMF.

S710, the network side selects MB-UPF to complete the second PDU session establishment flow.

It should be appreciated that S707-S710 are similar to S608-S611 in method 600 and are not repeated herein for brevity.

As another possible implementation, at S706, the SMF sends to the AMF a first correspondence of the MB-SMF ID, the first request information, and the first PDU session ID. Correspondingly, the AMF receives the first correspondence from the SMF and stores the first correspondence locally. In S707, the UE includes the second PDU session ID and the first PDU session ID in a second PDU session establishment request message transmitted to the AMF. Correspondingly, the AMF receives a second PDU session establishment request message from the UE, acquires a second PDU session ID and a first PDU session ID, then determines an MB-SMF ID and first request information according to the first PDU session ID and the first correspondence, then selects a corresponding MB-SMF as a session management network element of the second PDU session according to the MB-SMF ID, and then carries first request information corresponding to the first PDU session in a session management context request message of S709.

Fig. 8 is a schematic diagram of a system architecture 800 for applying the methods 600 and 700. In system architecture 800, UE1, UE2, UE3 are members of a multicast group and UE4 is a multicast source for the multicast group. In the PDU session establishment flow of the UE4, the MB-UPF corresponding to the multicast group is selected AS the PSA UPF of the new session of the UE4, when the UE4 is used AS a multicast source to send multicast data to the multicast group, the PSA UPF is not needed to send the multicast data to the AS, and the AS is used to forward the multicast data to the MB-UPF, thereby avoiding the detour of a transmission path during multicast communication and reducing the transmission delay of the multicast communication.

Fig. 9 is a schematic flow chart of a method 900 provided by an embodiment of the present application. In the embodiment shown in fig. 9, the UE requests the multicast source AS the first multicast group, and the multicast data transmitted by the UE AS the multicast source does not need AS parsing. As can be seen in fig. 9, method 900 includes:

and S901, completing the configuration of the first multicast group between the network equipment and the UE.

S902, the UE sends a first PDU session modification request message to the AMF, where the first PDU session modification request message includes first request information and a first multicast group identifier. The first multicast group identifier is used to identify a first multicast group, and the first multicast group identifier may be, for example, a multicast address of the first multicast group, and the first request information is used to request the UE to serve as a multicast source of the first multicast group.

S903, the AMF sends a session management context update request message to the SMF, where the session management context update request message includes the first request information and the first multicast group identifier.

In another possible implementation, the first request information and the first multicast group identification may also be sent by the AF to the SMF. For example, in S904, the AF sends a second message to the SMF, where the second message includes the first request information and the first multicast group identification.

It should be appreciated that S901-S904 are similar to S701-S704 in method 700 and for brevity, the description will not be repeated here.

Further, the SMF acquires MB-UPF information. Two schemes for the SMF to obtain the information of the MB-UPF are described below:

scheme 1:

s905, the SMF checks the authorization of the UE as a multicast source and acquires the MB-SMF ID.

It should be appreciated that S905 is similar to S606 in method 600 and for brevity, the description is not repeated here.

It should be noted that the scheme of this embodiment is applicable to both ASM model and SSM model of the first multicast group.

S906, the SMF acquires the MB-UPF information through the MB-SMF.

Illustratively, the SMF sends a request message to the MB-SMF according to the MB-SMF ID, where the request message carries a first multicast group identifier, where the request message requests to obtain MB-UPF address information; correspondingly, after receiving the request message, the MB-SMF obtains information of the MB-UPF corresponding to the first multicast group identifier according to the first multicast group identifier, for example, the address information of the MB-UPF or DNAI of the MB-UPF. The MB-SMF then replies to the SMF with MB-UPF information.

Scheme 2:

s907, the SMF checks the authorization of the UE as a multicast source and acquires the MB-UPF ID.

It should be understood that the scheme of SMF checking the authorization of the UE as the multicast source is similar to the related scheme in S606 in the method 600, and will not be described in detail herein.

When the UE has authorization as a multicast source of the first multicast group, the SMF acquires information of the MB-UMF, such as address information of the MB-UPF or DNAI of the MB-UPF, from the UDR according to the first multicast group identification.

It should be appreciated that for scheme 2, during the first multicast group configuration, the MB-SMF stores the address information of the MB-UPF or DNAI of the MB-UPF into the UDR.

S908, the network side uses the MB-UPF as an additional PSA UPF of the first PDU session, inserts or selects an existing UPF in the user plane, and configures the UPF to have the function of UL CL or BP.

Illustratively, after the SMF obtains the information of the MB-UPF, the MB-UPF is used as an additional PSA UPF of the first PDU session, and a UPF is inserted or an existing UPF is selected on the user plane according to the information of the MB-UPF, and the corresponding configuration is performed through the N4 session, so that the UPF has the function of UL CL or BP, thereby realizing the effect of shunting the multicast data of the UE to the MB-UPF. It should be appreciated that the UPF with UL CL or BP functionality may be the same UPF entity as the MB-UPF or the PSA UPF for the PDU session.

Therefore, in the communication method provided by the embodiment of the application, in the PDU session modification flow, the MB-UPF of the multicast group corresponding to the multicast source UE is selected as the additional PSA UPF of the first PDU session, and the distribution of the multicast data of the UE to the MB-UPF is realized by using the inserted UPF or the selected UPF as the UL CL/BP, so that the transmission path of the multicast data from the multicast source UE to the MB-UPF is constructed, the detour of the transmission path can be reduced, and the transmission delay is reduced.

Fig. 10 is a schematic diagram of a system architecture 1000 for applying the method 900. In system architecture 1000, UE1, UE2, UE3 are members of a multicast group and UE4 is a multicast source for the multicast group. UE4 sets the MB-UPF of the multicast group corresponding to UE4 as the extra PSA UPF of one PDU session by modifying that PDU session. By inserting a UPF on a line between the RAN and the original PSA UPF, or selecting an existing UPF on a line between the RAN and the original PSA UPF, and configuring a UL CL or BP function for the UPF, a transmission path of multicast data from the UE4 to the MB-UPF is constructed, when the UE4 is used AS a multicast source to send the multicast data to a multicast group, the multicast data is not required to be sent to an AS through the PSA UPF, and the multicast data is forwarded to the MB-UPF through the AS, thereby avoiding the detour of the transmission path during multicast communication and reducing the transmission delay of the multicast communication.

Fig. 11 is a schematic flow chart diagram of a method 1100 provided by an embodiment of the present application. In the embodiment shown in fig. 11, the UE requests to join the first multicast group and the UE does not support accepting multicast data in a multicast manner or the RAN in which the UE is located does not support multicast services. As can be seen in fig. 11, the method 1100 includes:

s1101, the first multicast group configuration is completed between the network device and the UE.

S1102, the UE sends a first PDU session establishment request message to the AMF.

Illustratively, the UE sends a first PDU session establishment request message to the AMF via the RAN, the first PDU session establishment request message requesting establishment of a first PDU session between the UE and the data network DN. The first PDU session establishment request message includes a first multicast group identifier, where the first multicast group identifier is used to identify a first multicast group, and the first multicast group identifier may be, for example, a multicast address of the first multicast group, where the first multicast identifier is used to indicate that the UE requests to join the first multicast group.

S1103, the AMF selects SMF.

S1104, the AMF sends a session management context request message to the SMF.

Illustratively, the AMF transmits a session management context request message for requesting establishment of the first PDU session management context to the SMF selected in S603. Optionally, the session management context request message includes a first multicast group identification.

S1105, the SMF sends a session management context response message to the AMF.

Illustratively, after receiving the session management context request message sent by the AMF, the SMF creates a session management context for the first PDU session and then sends a session management context response message to the AMF.

S1106, the SMF checks the authorization of the UE to join the multicast group and acquires the MB-SMF ID.

Illustratively, the SMF obtains authorization information for the multicast members of the first multicast group from the UDR, and determines from the authorization information whether the UE is authorized to join the multicast group.

S1107, the SMF transmits a first message to the UE, the first message including the first information, the second information, and the MB-SMF ID.

It should be understood that S1107 is similar to S607 in the method 600, and is not described herein for brevity.

S1108, the UE sends a second PDU session establishment request message to the AMF.

The UE may send a second PDU session establishment request message to the AMF according to the second information, the second PDU session establishment request message requesting establishment of a second PDU session. The second PDU session establishment request message includes the MB-SMF ID and the first multicast group identification.

S1109, AMF selects MB-SMF.

Illustratively, the AMF receives a second PDU session establishment request message from the UE, and obtains the MB-SMF ID carried in the second PDU session establishment request message, and the SMF selects the MB-SMF to establish the second PDU session according to the MB-SMF ID.

S1110, the AMF sends a session management context request message to the MB-SMF.

Illustratively, the AMF sends a session management context request message to the MB-SMF requesting establishment of the second PDU session management context. The session management context request message includes a first multicast group identification.

As another possible implementation, at S1107, the SMF sends to the AMF a first correspondence of the MB-SMF ID, the first multicast group identification, and the first PDU session ID. Correspondingly, the AMF receives the first correspondence from the SMF and stores the first correspondence locally. In S1108, the UE includes the second PDU session ID and the first PDU session ID in the second PDU session establishment request message transmitted to the AMF. Correspondingly, the AMF receives a second PDU session establishment request message from the UE, acquires a second PDU session ID and a first PDU session ID, then determines an MB-SMF ID and first request information according to the first PDU session ID and a first correspondence, then selects a corresponding MB-SMF as a session management network element of the second PDU session according to the MB-SMF ID, and then carries a first multicast group identifier corresponding to the first PDU session in a session management context request message of S1110.

S1111, the network side selects MB-UPF to complete the second PDU session establishment procedure.

Illustratively, after receiving a session management context request message sent by the AMF, the MB-SMF obtains a first multicast group identifier in the session management context request message, and determines, according to the first multicast group identifier, that the UE requests to join the first multicast group. The MB-SMF finds the MB-UPF from the corresponding first multicast context according to the first multicast group identification, and selects the MB-UPF as the PSA UPF for the second PDU session. The specific manner in which the network side continues to complete the establishment of the second PDU session is not limited.

Therefore, in the communication method provided by the embodiment of the application, when the UE serving as a multicast group member does not support receiving multicast data in a multicast manner or the RAN where the UE is located does not support multicast service, in the PDU session establishment flow, by directly selecting the MB-UPF of the multicast group corresponding to the multicast group member UE as the PSA UPF of the new session of the UE, a transmission path from the MB-UPF to the multicast data of the multicast group member UE is constructed, so that the detour of the transmission path can be reduced, and the transmission delay can be reduced.

Fig. 12 is a schematic flow chart diagram of a method 1200 provided by an embodiment of the present application. In the embodiment shown in fig. 12, the UE requests to join the first multicast group, the UE does not support accepting multicast data in a multicast manner, or the RAN in which the UE is located does not support multicast services. As can be seen in fig. 12, method 1200 includes:

S1201, the first multicast group configuration is completed between the network device and the UE.

S1202, the UE sends a first PDU session modification request message to the AMF, where the first PDU session modification request message includes a first multicast group identifier, where the first multicast group identifier is used to identify a first multicast group, and the first multicast group identifier may be, for example, a multicast address of the first multicast group, where the first multicast group identifier is used to indicate that the UE requests to join the first multicast group.

S1203, the AMF sends a session management context update request message to the SMF, where the session management context update request message includes the first multicast group identifier.

In another possible implementation, the first multicast group identification may also be sent by the AF to the SMF. For example, in S704, the AF sends a first message to the SMF, where the first message includes a first multicast group identification. The first message may be, for example, a request message for the UE to join the first multicast group. It should be appreciated that the AF may send the first message directly to the SMF or may forward via the NEF.

S1205, the SMF checks the authorization of the UE to join the multicast group and obtains the MB-SMF ID.

It should be appreciated that S1205 is similar to S1106 in method 1100, and the description is not repeated here.

S1206, the SMF sends a first message to the UE, where the first message includes the second information and the MB-SMF ID.

S1207, the UE sends a second PDU session establishment request message to the AMF, where the second PDU session establishment request message includes the first multicast group identifier and the MB-SMF ID.

The UE may send a second PDU session establishment request message to the AMF according to the second information, the second PDU session establishment request message requesting establishment of a second PDU session. The second PDU session establishment request message includes an MB-SMF ID and a first multicast group identifier, where the first multicast group identifier is used to instruct the UE to request to join the first multicast group.

S1208, AMF selects MB-SMF.

S1209, the AMF sends a session management context request message to the MB-SMF.

S1210, the network side selects MB-UPF to complete the second PDU session establishment procedure.

It should be appreciated that S1208-S1210 are similar to S609-S611 in method 600, and for brevity, the description will not be repeated here.

As another possible implementation, at S1206, the SMF sends to the AMF a first correspondence of the MB-SMF ID, the first multicast group identification, and the first PDU session ID. Correspondingly, the AMF receives the first correspondence from the SMF and stores the first correspondence locally. In S608, the second PDU session ID and the first PDU session ID are included in the second PDU session establishment request message transmitted by the UE to the AMF. Correspondingly, the AMF receives the second PDU session establishment request message from the UE, and obtains the second PDU session ID and the first PDU session ID, then the AMF determines the MB-SMF ID and the first request information according to the first PDU session ID and the first correspondence, then the AMF selects the corresponding MB-SMF as a session management network element of the second PDU session according to the MB-SMF ID, and then the AMF carries the first multicast group identifier corresponding to the first PDU session in the session management context request message of S1209.

Fig. 13 is a schematic diagram of a system architecture 1300 for applying the methods 1100 and 1200. In the system architecture 1300, UE1, UE2, and UE3 are all members of a multicast group, where UE1 and UE2 support multicast data reception in a multicast manner, RAN1 where UE1 and UE2 are located also supports multicast services, and UE3 does not support multicast data reception in a multicast manner, or RAN2 where UE3 is located does not support multicast services. In the PDU session establishment flow of the UE3, the MB-UPF corresponding to the multicast group is selected as the PSA UPF of the new session of the UE3, after the multicast data packet arrives at the MB-UPF, the data does not need to be forwarded to the PSA UPF, and the multicast data is sent to the RAN2 through the PSA UPF, so that the detour of a transmission path during multicast communication is avoided, and the transmission delay of the multicast communication can be reduced.

Fig. 14 is a schematic flow chart diagram of a method 1400 provided by an embodiment of the present application. In the embodiment shown in fig. 14, the UE requests to join the first multicast group, the UE does not support accepting multicast data in a multicast manner, or the RAN in which the UE is located does not support multicast services. As can be seen in fig. 14, the method 1400 includes:

s1401, the first multicast group configuration is completed between the network device and the UE.

S1402, the UE sends a first PDU session modification request message to the AMF, where the first PDU session modification request message includes a first multicast group identifier. The first multicast group identity is used to identify a first multicast group, which may be, for example, a multicast address of the first multicast group, the first multicast group identity being used to indicate that the UE requests to join the first multicast group.

S1403, the AMF sends a session management context update request message to the SMF, where the session management context update request message includes the first multicast group identifier.

In another possible implementation, the first multicast group identification may also be sent by the AF to the SMF. For example, in S1404, the AF sends a first message to the SMF, the first message including a first multicast group identification. The first message may be, for example, a request message for the UE to join the first multicast group. It should be appreciated that the AF may send the first message directly to the SMF or may forward via the NEF.

Further, the SMF acquires MB-UPF information.

It should be understood that S1405 to S1407 are similar to S905 to S907 in the method 900, except that the SMF checks the authorization of the UE to join the multicast group in S1405 and S1407, and the description is not repeated in the present application for brevity.

S1408, the network side uses the MB-UPF as an additional PSA UPF for the first PDU session, inserts or selects an existing UPF in the user plane, and configures the UPF to have the UL CL or BP function.

It should be appreciated that S1408 is similar to S908 in method 900 and for brevity, the description will not be repeated.

Therefore, in the communication method provided by the embodiment of the application, when the UE serving as a multicast group member does not support receiving multicast data in a multicast manner or the RAN where the UE is located does not support multicast service, in the PDU session modification flow, the MB-UPF of the multicast group corresponding to the multicast group member UE is selected as the extra PSA UPF of the first PDU session, and the split flow of the multicast data to the UE is realized by using the inserted UPF or the selected UPF as the UL CL/BP, so that the transmission path of the multicast data from the MB-UPF to the multicast member UE is constructed, thereby reducing the detour of the transmission path and reducing the transmission delay.

Fig. 15 is a schematic diagram of a system architecture 1500 for applying the method 1400. In the system architecture 1500, UE1, UE2, and UE3 are all members of a multicast group, where UE1 and UE2 support multicast data reception in a multicast manner, RAN1 where UE1 and UE2 are located also supports multicast services, and UE3 does not support multicast data reception in a multicast manner, or RAN2 where UE3 is located does not support multicast services. UE3 sets the MB-UPF of the multicast group corresponding to UE3 as the extra PSA UPF of one PDU session by modifying that PDU session. By inserting a UPF on the user plane path between the RAN and the primary PSA UPF, or selecting an existing UPF on the user plane path between the RAN and the original PSA UPF, and configuring the UL CL or BP function for the UPF, a transmission path of multicast data from the UE3 to the MB-UPF is constructed, and at this time, after the multicast data packet arrives at the MB-UPF, the data is not required to be forwarded to the primary PSA UPF, and then the multicast data is sent to the RAN2 through the primary PSA UPF, thereby avoiding the detour of the transmission path during multicast communication and reducing the transmission delay of the multicast communication.

The method provided in the embodiment of the present application is described in detail above with reference to fig. 5 to 15. The following describes in detail the communication device provided in the embodiment of the present application with reference to fig. 16 to 19.

Fig. 16 is a schematic block diagram of a communication device 10 provided in an embodiment of the present application. As shown, the communication device 10 may include a transceiver module 11 and a processing module 12.

In one possible design, the communication device 10 may correspond to a terminal equipment or UE in the above method embodiments.

Illustratively, the communication apparatus 10 may correspond to the terminal device or UE in the methods 500-700, 900, 1100-1200, 1400 according to embodiments of the present application, the communication apparatus 10 may include means for performing the methods 500, 600, 700, 900, 1100, 1200, and 1400 in fig. 5, 6, 7, 9, 11, 12, and 14. And, each unit in the communication device 10 and the other operations and/or functions described above are respectively for implementing the respective flows of the methods 500 to 700, 900, 1100 to 1200, 1400.

The transceiver module 11 in the communication apparatus 10 performs the receiving and transmitting operations performed by the terminal device or UE in the above-described method embodiments, and the processing module 12 performs operations other than the receiving and transmitting operations.

In another possible design, the communication device 10 may correspond to a session management network element or SMF in the above method embodiments.

Illustratively, the communication device 10 may correspond to the session management network element or SMF in the methods 500-700, 900, 1100-1200, 1400 according to embodiments of the present application, the communication device 10 may comprise means for performing the method 500 in fig. 5, the method 600 in fig. 6, the method 700 in fig. 7, the method 900 in fig. 9, the method 1100 in fig. 11, the method 1200 in fig. 12, and the method 1400 in fig. 14. And, each unit in the communication device 10 and the other operations and/or functions described above are respectively for implementing the respective flows of the methods 500 to 700, 900, 1100 to 1200, 1400.

The transceiver module 11 in the communication device 10 performs the receiving and transmitting operations performed by the session management network element or the SMF in the above-described method embodiments, and the processing module 12 performs operations other than the receiving and transmitting operations.

In yet another possible design, the communication device 10 may correspond to a mobility management network element or AMF in the above method embodiment.

Illustratively, the communication device 10 may correspond to the mobility management network element or AMF in the methods 500-700, 900, 1100-1200, 1400 according to embodiments of the present application, the communication device 10 may comprise means for performing the methods 500, 600, 700, 900, 1100, 1200, and 1400 in fig. 5, 6, 9, respectively. And, each unit in the communication device 10 and the other operations and/or functions described above are respectively for implementing the respective flows of the methods 500 to 700, 900, 1100 to 1200, 1400.

The transceiver module 11 in the communication device 10 performs the receiving and transmitting operations performed by the mobility management element or the AMF in the above-described method embodiments, and the processing module 12 performs operations other than the receiving and transmitting operations.

According to the foregoing method, fig. 17 is a schematic diagram of a communication apparatus 20 provided in the embodiment of the present application, and as shown in fig. 17, the apparatus 20 may be a terminal device or a network device, and the network device may be, for example, a session management network element or a mobility management network element.

The apparatus 20 may include a processor 21 (i.e., an example of a processing module) and a memory 22. The memory 22 is configured to store instructions, and the processor 21 is configured to execute the instructions stored in the memory 22, so that the apparatus 20 implements steps performed by a terminal device or UE or session management network element or SMF or mobility management network element or AMF in a method corresponding to fig. 5, 6, 7, 9, 11, 12, and 14.

Further, the apparatus 20 may also include an input port 23 (i.e., one example of a transceiver module) and an output port 24 (i.e., another example of a transceiver module). Further, the processor 21, memory 22, input port 23 and output port 24 may communicate with each other via internal connection paths to communicate control and/or data signals. The memory 22 is used for storing a computer program, and the processor 21 may be used for calling and running the computer program from the memory 22 to control the input port 23 to receive signals and the output port 24 to send signals, so as to complete the steps of the network device in the method. The memory 22 may be integrated in the processor 21 or may be provided separately from the processor 21.

Alternatively, if the communication device 20 is a communication apparatus, the input port 23 is a receiver, and the output port 24 is a transmitter. Wherein the receiver and the transmitter may be the same or different physical entities. Which are the same physical entities, may be collectively referred to as transceivers.

Alternatively, if the communication device 20 is a chip or a circuit, the input port 23 is an input interface, and the output port 24 is an output interface.

As an implementation, the functions of the input port 23 and the output port 24 may be considered to be implemented by a transceiving circuit or a dedicated chip for transceiving. The processor 21 may be considered to be implemented by a dedicated processing chip, a processing circuit, a processor, or a general-purpose chip.

As another implementation manner, a manner of using a general-purpose computer may be considered to implement the communication device provided in the embodiments of the present application. I.e. program code that implements the functions of the processor 21, the input port 23 and the output port 24 is stored in the memory 22, and the general purpose processor implements the functions of the processor 21, the input port 23 and the output port 24 by executing the code in the memory 22.

The concepts related to the technical solutions provided in the embodiments of the present application, explanation and detailed description of the concepts related to the device 20 and other steps are referred to in the foregoing methods or descriptions related to the other embodiments, and are not repeated herein.

Fig. 18 is a schematic structural diagram of a terminal device 30 provided in the present application. For ease of illustration, fig. 18 shows only the main components of the communication device. As shown in fig. 18, the terminal device 30 includes a processor, a memory, a control circuit, an antenna, and input-output means.

The processor is mainly configured to process the communication protocol and the communication data, control the entire terminal device, execute a software program, and process the data of the software program, for example, to support the terminal device to execute the actions described in the above embodiment of the method for indicating the transmission precoding matrix. The memory is mainly used for storing software programs and data, for example, for storing the codebook described in the above embodiments. The control circuit is mainly used for converting baseband signals and radio frequency signals and processing the radio frequency signals. The control circuit together with the antenna, which may also be called a transceiver, is mainly used for receiving and transmitting radio frequency signals in the form of electromagnetic waves. Input and output devices, such as touch screens, display screens, keyboards, etc., are mainly used for receiving data input by a user and outputting data to the user.

When the communication device is started, the processor can read the software program in the storage unit, interpret and execute the instructions of the software program and process the data of the software program. When data is required to be transmitted wirelessly, the processor carries out baseband processing on the data to be transmitted and then outputs a baseband signal to the radio frequency circuit, and the radio frequency circuit carries out radio frequency processing on the baseband signal and then transmits the radio frequency signal outwards in the form of electromagnetic waves through the antenna. When data is sent to the terminal equipment, the radio frequency circuit receives a radio frequency signal through the antenna, converts the radio frequency signal into a baseband signal, and outputs the baseband signal to the processor, and the processor converts the baseband signal into data and processes the data.

Those skilled in the art will appreciate that fig. 18 shows only one memory and processor for ease of illustration. In an actual terminal device, there may be multiple processors and memories. The memory may also be referred to as a storage medium or storage device, etc., and embodiments of the present application are not limited in this regard.

As an alternative implementation manner, the processor may include a baseband processor, which is mainly used for processing the communication protocol and the communication data, and a central processor, which is mainly used for controlling the whole terminal device, executing a software program, and processing the data of the software program. The processor in fig. 18 integrates the functions of a baseband processor and a central processing unit, and those skilled in the art will appreciate that the baseband processor and the central processing unit may be separate processors, interconnected by bus technology, etc. Those skilled in the art will appreciate that the terminal device may include multiple baseband processors to accommodate different network formats, and that the terminal device may include multiple central processors to enhance its processing capabilities, and that the various components of the terminal device may be connected by various buses. The baseband processor may also be expressed as a baseband processing circuit or a baseband processing chip. The central processing unit may also be expressed as a central processing circuit or a central processing chip. The function of processing the communication protocol and the communication data may be built in the processor, or may be stored in the storage unit in the form of a software program, which is executed by the processor to realize the baseband processing function.

As shown in fig. 18, the terminal device 30 includes a transceiving unit 31 and a processing unit 32. The transceiver unit may also be referred to as a transceiver, transceiver device, etc. Alternatively, the device for implementing the receiving function in the transceiver unit 31 may be regarded as a receiving unit, and the device for implementing the transmitting function in the transceiver unit 31 may be regarded as a transmitting unit, that is, the transceiver unit 31 includes a receiving unit and a transmitting unit. For example, the receiving unit may also be referred to as a receiver, a receiving circuit, etc., and the transmitting unit may be referred to as a transmitter, a transmitting circuit, etc.

The terminal device shown in fig. 18 may perform the actions performed by the terminal device or UE in the methods 500 to 700, 900, 1100 to 1200, and 1400, and detailed descriptions thereof are omitted here for avoiding redundancy.

Fig. 19 shows a simplified schematic diagram of the structure of a network device 40. The network device includes a portion 41 and a portion 42. The part 41 is mainly used for receiving and transmitting radio frequency signals and converting the radio frequency signals and baseband signals; the 42 part is mainly used for baseband processing, control of network equipment and the like. Section 41 may be generally referred to as a transceiver module, transceiver circuitry, or transceiver, etc. Portion 42 is typically a control center of the network device, and may be generally referred to as a processing module, for controlling the network device to perform the processing operations on the network device side in the above-described method embodiment.

The transceiver module of section 41, which may also be referred to as a transceiver or transceiver, includes an antenna and radio frequency circuitry, wherein the radio frequency circuitry is primarily for radio frequency processing. For example, the device for realizing the receiving function in part 41 may be regarded as a receiving module, and the device for realizing the transmitting function may be regarded as a transmitting module, i.e., part 41 includes a receiving module and a transmitting module. The receiving module may also be referred to as a receiver, or a receiving circuit, etc., and the transmitting module may be referred to as a transmitter, or a transmitting circuit, etc.

Portion 42 may include one or more boards, each of which may include one or more processors and one or more memories. The processor is used for reading and executing the program in the memory to realize the baseband processing function and control the network equipment. If there are multiple boards, the boards can be interconnected to enhance processing power. As an alternative implementation manner, the multiple boards may share one or more processors, or the multiple boards may share one or more memories, or the multiple boards may share one or more processors at the same time.

For example, in one implementation, the network device shown in fig. 19 may be any of the network devices shown in fig. 5, 6, 7, 9, 11, 12, 14, e.g., a session management network element, a mobility management network element, an SMF, an AMF, etc.

The transceiver module of section 41 is configured to perform the steps associated with the transceiving of any of the network devices of method 500 in fig. 5, method 600 in fig. 6, method 700 in fig. 7, method 900 in fig. 9, method 1100 in fig. 11, method 1200 in fig. 12, and method 1400 in fig. 14; 42 are used, in part, to perform the process-related steps of method 500 in fig. 5, method 600 in fig. 6, method 700 in fig. 7, method 900 in fig. 9, method 1100 in fig. 11, method 1200 in fig. 12, and any network device in method 1400 in fig. 14.

It should be understood that fig. 19 is only an example and not a limitation, and that the network device including the transceiver module and the processing module may not depend on the structure shown in fig. 19.

When the device 40 is a chip, the chip includes a transceiver module and a processing module. The transceiver module can be an input/output circuit and a communication interface; the processing module is an integrated processor or microprocessor or integrated circuit on the chip.

The present application also provides a computer readable storage medium having stored thereon computer instructions for implementing the method performed by the first network device in the above method embodiment.

For example, the computer program, when executed by a computer, enables the computer to implement the method performed by the network device in the method embodiments described above.

Embodiments of the present application also provide a computer program product containing instructions that, when executed by a computer, cause the computer to implement the method performed by the first device or the method performed by the second device in the method embodiments described above.

The embodiment of the application also provides a communication system, which comprises the network device in the embodiment.

The explanation and beneficial effects of the related content in any of the above-mentioned devices can refer to the corresponding method embodiments provided above, and are not repeated here.

In embodiments of the present application, the network device may include a hardware layer, an operating system layer running above the hardware layer, and an application layer running above the operating system layer. The hardware layer may include a central processing unit (central processing unit, CPU), a memory management unit (memory management unit, MMU), and a memory (also referred to as a main memory). The operating system of the operating system layer may be any one or more computer operating systems that implement business processing through processes (processes), for example, a Linux operating system, a Unix operating system, an Android operating system, an iOS operating system, or windows operating system, etc. The application layer may include applications such as a browser, address book, word processor, instant messaging software, and the like.

The present embodiment does not particularly limit the specific structure of the execution body of the method provided in the present embodiment, as long as communication can be performed in the method provided in the present embodiment by running a program in which the code of the method provided in the present embodiment is recorded. For example, the execution body of the method provided in the embodiment of the present application may be a network device, or a functional module in the network device that can call a program and execute the program.

Various aspects or features of the present application can be implemented as a method, apparatus, or article of manufacture using standard programming and/or engineering techniques. The term "article of manufacture" as used herein may encompass a computer program accessible from any computer-readable device, carrier, or media. For example, computer-readable media may include, but are not limited to: magnetic storage devices (e.g., hard disk, floppy disk, or magnetic tape, etc.), optical disks (e.g., compact Disk (CD), digital versatile disk (digital versatile disc, DVD), etc.), smart cards, and flash memory devices (e.g., erasable programmable read-only memory (EPROM), cards, sticks, key drives, etc.).

Various storage media described herein can represent one or more devices and/or other machine-readable media for storing information. The term "machine-readable medium" may include, but is not limited to: wireless channels, and various other media capable of storing, containing, and/or carrying instruction(s) and/or data.

It should be appreciated that the processors referred to in the embodiments of the present application may be central processing units (central processing unit, CPU), but may also be other general purpose processors, digital signal processors (digital signal processor, DSP), application specific integrated circuits (application specific integrated circuit, ASIC), off-the-shelf programmable gate arrays (field programmable gate array, FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or 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 referred to in the embodiments of the present application may be volatile memory or nonvolatile memory, or may include both volatile and nonvolatile memory. The nonvolatile memory may be a read-only memory (ROM), a Programmable ROM (PROM), an Erasable PROM (EPROM), an electrically Erasable EPROM (EEPROM), or a flash memory. The volatile memory may be random access memory (random access memory, RAM). For example, RAM may be used as an external cache. By way of example, and not limitation, RAM may include the following forms: static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous DRAM (SLDRAM), and direct memory bus RAM (DR RAM).

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

It should also be noted that the memory described herein is intended to comprise, without being limited to, these and any other suitable types of memory.

Those of ordinary skill in the art will appreciate that the elements and steps of the examples described in connection with the embodiments disclosed herein can be implemented as electronic hardware, or as a combination of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

It will be clear to those skilled in the art that, for convenience and brevity, the specific working procedures of the apparatus and units described above may refer to the corresponding procedures in the foregoing method embodiments, which are not described herein again.

In the several embodiments provided in this application, it should be understood that the disclosed apparatus and method may be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative, e.g., the division of the units is merely a logical function division, and there may be additional divisions when actually implemented, e.g., multiple units or components may be combined or integrated into another system, or some features may be omitted or not performed. Furthermore, the coupling or direct coupling or communication connection shown or discussed with each other may be through some interface, device or unit indirect coupling or communication connection, which may be in electrical, mechanical or other form.

The units described as separate units may or may not be physically separate, and units shown as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units may be selected according to actual needs to implement the solution provided in the present application.

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

In the above embodiments, it may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented in software, may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When loaded and executed on a computer, produces a flow or function in accordance with embodiments of the present application, in whole or in part. The computer may be a general purpose computer, a special purpose computer, a computer network, or other programmable apparatus. For example, the computer may be a personal computer, a server, or a network device, etc. The computer instructions may be stored in or transmitted from one computer-readable storage medium to another, for example, by wired (e.g., coaxial cable, optical fiber, digital Subscriber Line (DSL)), or wireless (e.g., infrared, wireless, microwave, etc.). The computer readable storage medium may be any available medium that can be accessed by a computer or a data storage device such as a server, data center, etc. that contains an integration of one or more available media. For example, the aforementioned usable medium may include, but is not limited to, a U disk, a removable hard disk, a read-only memory (ROM), a random access memory (random access memory, RAM), a magnetic disk or an optical disk, etc. various media that can store program codes.

The foregoing is merely specific embodiments of the present application, but the scope of the present application is not limited thereto, and any changes or substitutions easily conceivable by those skilled in the art within the technical scope of the present application should be covered in the scope of the present application. The scope of the application is therefore intended to be covered by the following claims and this description.

Claims

1. A method of communication, comprising:

receiving first request information and an identifier of a first multicast group, wherein the first request information is used for requesting a terminal device to become a multicast source of the first multicast group, or the first request information is used for requesting the terminal device to join the first multicast group;

sending second request information and an identifier of the first multicast group to a data management network element, wherein the second request information is used for requesting to acquire the identifier of a first session management network element, the first session management network element is used for multicast session management, and the first session management network element is associated with the identifier of the first multicast group;

an identification of the first session management network element from the data management network element is received.

2. The method according to claim 1, wherein the method further comprises:

And sending the identification of the first session management network element to a mobile management network element.

3. The method according to claim 1 or 2, characterized in that before said sending the second request information and the first multicast group identification to the data management network element, the method further comprises:

and sending third request information to the data management network element, wherein the third request information is used for requesting to verify that the terminal equipment is authorized to serve as a multicast source of the first multicast group when the first request information is used for requesting the terminal equipment to serve as a multicast source of the first multicast group, and requesting to verify that the terminal equipment is authorized to join the first multicast group when the first request information is used for requesting the terminal equipment to join the first multicast group.

4. A method according to any one of claims 1 to 3, further comprising:

and sending first indication information and an identifier of the first session management network element to the terminal equipment, wherein the first session management network element is used for multicast session management, and the first indication information is used for indicating the terminal equipment to establish the first session.

5. A method according to claim 3, characterized in that the method further comprises:

and acquiring information of a first user plane functional network element, wherein the first user plane functional network element is used for forwarding multicast data, and the first user plane functional network element is associated with the first multicast group identifier.

6. The method of claim 5, wherein after the obtaining the information of the first user plane function network element, the method further comprises:

and constructing a data transmission path between the first user plane functional network element and the terminal equipment according to the information of the first user plane functional network element.

7. The method according to claim 5 or 6, wherein the obtaining information of the first user plane functional network element comprises:

sending fourth request information and an identifier of the first multicast group to the data management network element, wherein the fourth request information is used for requesting to acquire the information of the first user plane functional network element;

receiving information of the first user plane function network element from the data management network element; or,

transmitting the fourth request information and the identification of the first multicast group to the first session management network element;

Information of the first user plane function network element from the first session management network element is received.

8. The method according to any one of claims 1 to 7, wherein the receiving the first request information and the identification of the first multicast group comprises:

receiving the first request information from the terminal equipment and the identification of the first multicast group; or alternatively

And receiving the first request information from the application function network element and the identification of the first multicast group.

9. A method of communication, comprising:

receiving a first session establishment request message from a terminal device, wherein the first session establishment request message is used for requesting to establish a first session between the terminal device and a data network, the first session establishment request message comprises an identifier of a first session management network element, and the first session management network element is used for multicast session management;

and sending first request information and an identifier of a first multicast group to the first session management network element, wherein the first request information is used for requesting a terminal device to become a multicast source of the first multicast group, or the first request information is used for requesting the terminal device to join the first multicast group.

10. The method of claim 9, wherein prior to the receiving the first session establishment request message from the terminal device, the method further comprises:

receiving the first request information from the terminal equipment and the identification of the first multicast group;

and sending the first request information and the identification of the first multicast group to a second session management network element.

11. The method of claim 10, wherein the receiving the first request information from the terminal device and the identification of the first multicast group comprises:

receiving a second session establishment request message from the terminal device, wherein the second session establishment request message comprises the first request information and the identification of the first multicast group; or alternatively

A second session modification request message is received from the terminal device, the second session modification request message comprising the first request information and an identification of the first multicast group.

12. A method of communication, comprising:

receiving first indication information from a second session management network element and an identifier of the first session management network element, wherein the first session management network element is used for multicast session management, and the first indication information is used for indicating terminal equipment to establish a first session;

And sending a first session establishment request message to a mobile management network element, wherein the first session establishment request message is used for requesting to establish the first session between the terminal equipment and the data network, the first session establishment request message comprises an identifier of the first session management network element, and the first session management network element is used for multicast session management.

13. The method according to claim 12, wherein before said sending a session establishment request message to a mobility management network element, the method further comprises:

and sending first request information and a first multicast group identifier to a mobile management network element, wherein the first request information is used for requesting a terminal device to become a multicast source of a first multicast group, or the first request information is used for requesting the terminal device to join the first multicast group.

14. The method of claim 13, wherein the sending the first request information and the first multicast group identification to the mobility management element comprises:

sending a second session establishment request message to the mobility management network element, wherein the second session establishment request message comprises the first request information and the identifier of the first multicast group; or,

And sending a second session modification request message to the mobile management network element, wherein the second session modification request message comprises the first request information and the identification of the first multicast group.

15. A communication device, comprising:

the receiving and transmitting module is used for receiving first request information and an identifier of a first multicast group, wherein the first request information is used for requesting the terminal equipment to become a multicast source of the first multicast group or requesting the terminal equipment to join the first multicast group;

the receiving and transmitting module is further configured to send second request information and an identifier of the first multicast group to a data management network element, where the second request information is used to request to obtain an identifier of a first session management network element, the first session management network element is used to perform multicast session management, and the first session management network element is associated with the identifier of the first multicast group;

the transceiver module is further configured to receive an identification of the first session management network element from the data management network element.

16. The apparatus of claim 15, wherein the transceiver module is further configured to:

17. The apparatus of claim 15 or 16, wherein the transceiver module is further configured to:

18. The apparatus of any one of claims 15 to 17, wherein the transceiver module is further configured to:

19. The apparatus of claim 17, wherein the apparatus further comprises:

the processing module is used for acquiring information of a first user plane functional network element, the first user plane functional network element is used for forwarding multicast data, and the first user plane functional network element is associated with the first multicast group identifier.

20. The apparatus of claim 19, wherein the processing module is further configured to:

21. The apparatus according to claim 19 or 20, wherein the processing module is specifically configured to:

transmitting fourth request information and the identifier of the first multicast group to the data management network element through the transceiver module, wherein the fourth request information is used for requesting to acquire the information of the first user plane function network element; and

receiving information of the first user plane function network element from the data management network element through the transceiver module; alternatively, the processing module is specifically configured to:

transmitting the fourth request information and the identification of the first multicast group to the first session management network element through the transceiver module; and

and receiving information of the first user plane function network element from the first session management network element through the transceiver module.

22. The apparatus according to any one of claims 15 to 21, wherein the transceiver module is specifically configured to:

23. A communication device, comprising:

a transceiver module, configured to receive a first session establishment request message from a terminal device, where the first session establishment request message is used to request establishment of a first session between the terminal device and a data network, where the first session establishment request message includes an identifier of a first session management network element, and the first session management network element is used to perform multicast session management;

the transceiver module is further configured to send first request information and an identifier of a first multicast group to the first session management network element, where the first request information is used to request a terminal device to be a multicast source of the first multicast group, or the first request information is used to request the terminal device to join the first multicast group.

24. The apparatus of claim 23, wherein the transceiver module is further configured to:

receiving the first request information from the terminal equipment and the identification of the first multicast group; and

25. The apparatus of claim 24, wherein the transceiver module is specifically configured to:

26. A communication device, comprising:

the receiving and transmitting module is used for receiving first indication information from the second session management network element and the identification of the first session management network element, wherein the first session management network element is used for multicast session management, and the first indication information is used for indicating the terminal equipment to establish a first session;

the transceiver module is further configured to send a first session establishment request message to a mobility management network element, where the first session establishment request message is used to request establishment of the first session between the terminal device and the data network, the first session establishment request message includes an identifier of the first session management network element, and the first session management network element is used to perform multicast session management.

27. The apparatus of claim 26, wherein the transceiver module is further configured to:

28. The apparatus of claim 27, wherein the transceiver module is specifically configured to:

29. A computer readable storage medium, characterized in that the computer readable storage medium stores a computer program which, when run on a computer, causes the computer to perform the method of any one of claims 1 to 14.

30. A chip comprising a processor and a memory, the memory for storing a computer program, the processor for invoking and running the computer program stored in the memory to perform the method of any of claims 1 to 14.