CN115052370A

CN115052370A - Point-to-multipoint data transmission method and device, electronic equipment and storage medium

Info

Publication number: CN115052370A
Application number: CN202110258383.2A
Authority: CN
Inventors: 李芸; 侯云静; 王胡成
Original assignee: Datang Mobile Communications Equipment Co Ltd
Current assignee: Datang Mobile Communications Equipment Co Ltd
Priority date: 2021-03-09
Filing date: 2021-03-09
Publication date: 2022-09-13

Abstract

The embodiment of the application provides a point-to-multipoint data transmission method, a point-to-multipoint data transmission device, electronic equipment and a storage medium, wherein the method comprises the following steps: determining a root User Plane Function (UPF) network element; sending a first N4session establishment request message to the root UPF network element; the first N4session establishment request message contains a first data forwarding rule; the first data forwarding rule is used for indicating a multicast data forwarding mode of the root UPF network element; the multicast data is point-to-multipoint T2mT data in the air-space-ground integrated network. According to the point-to-multipoint data transmission method, the point-to-multipoint data transmission device, the electronic equipment and the storage medium, the root UPF network element is introduced, the root UPF network element respectively carries out data transmission with other UPFs in the multicast group, a N9 tunnel between the UPF network elements does not need to be reestablished, resources are effectively utilized, and signaling overhead and resource consumption are saved.

Description

Point-to-multipoint data transmission method and device, electronic equipment and storage medium

Technical Field

The present application relates to the field of communications technologies, and in particular, to a point-to-multipoint data transmission method and apparatus, an electronic device, and a storage medium.

Background

In the existing 5G multicast/broadcast service (5G multicast/broadcast service,5MBS) technology, multicast Data transmission is performed between a 5G base station (gNB) and a User Plane Function (User Plane Function, UPF network element) network element by establishing a multicast session, Data transmission is performed by establishing a unicast tunnel by establishing a Protocol Data Unit (PDU) session, and Data transmission is performed between a terminal/User Equipment (User Equipment, UE) and the gNB by using a Radio bearer (Radio bearer, RB).

If the existing terrestrial general technology is used to support a Terminal-to-Multiple Terminal (T2 mT) service in an air-ground integrated network, when any UE in a multicast group sends a multicast request, tunnels need to be established between on-satellite UPF network elements, and between an on-satellite UPF network element and a gNB corresponding to the UE in the multicast group, and when different UEs in the multicast group send multicast data, if an N9 tunnel is not established between corresponding UPF network elements, an N9 tunnel between the UPF network elements needs to be re-established, which results in resource waste for a satellite of the air-ground integrated network.

Disclosure of Invention

The embodiment of the application provides a point-to-multipoint data transmission method and device, electronic equipment and a storage medium, and aims to solve the technical problem of low resource utilization rate in the point-to-multipoint data transmission process in an air-space-ground integrated network.

In a first aspect, an embodiment of the present application provides a point-to-multipoint data transmission method, including:

determining a root User Plane Function (UPF) network element;

sending a first N4session establishment request message to the root UPF network element; the first N4session establishment request message contains a first data forwarding rule; the first data forwarding rule is used for indicating a multicast data forwarding mode of the root UPF network element; the multicast data is point-to-multipoint T2mT data in the air-space-ground integrated network.

Optionally, according to a point-to-multipoint data transmission method of an embodiment of the present application, the determining a root user plane function UPF network element includes:

and taking the UPF network elements directly connected with all the UPF network elements in the multicast group as the root UPF network element.

and taking the UPF network element with the maximum number of terminal UE in the direct connection base station gNB in the multicast group as the root UPF network element.

and taking the UPF network element with the least user plane traffic as the root UPF network element.

Optionally, according to an embodiment of the present application, in the point-to-multipoint data transmission method, the first data forwarding rule includes:

if the root UPF network element receives multicast data sent by a gNB directly connected with the root UPF network element, the root UPF network element sends the multicast data to other UPF network elements in a multicast group;

if the root UPF network element receives the multicast data sent by any UPF network element in the multicast group, the root UPF network element sends the multicast data to other UPF network elements in the multicast group;

and if the root UPF network element receives multicast data sent by any UPF network element in the multicast group and the UE under the gNB directly connected with the root UPF network element is in the UE list in the multicast group, the root UPF network element sends the multicast data to other UPF network elements in the multicast group and the gNB directly connected with the root UPF network element.

Optionally, according to the point-to-multipoint data transmission method in an embodiment of the present application, after determining a root user plane function UPF network element, the method further includes:

sending a second N4session establishment request message to other UPF network elements in the multicast group; the second N4session establishment request message includes a second data forwarding rule; and the second data forwarding rule is used for indicating the mode of forwarding the multicast data by other UPF network elements in the multicast group.

Optionally, according to an embodiment of the present application, in the point-to-multipoint data transmission method, the second data forwarding rule includes:

if the other UPF network elements receive the multicast data sent by the root UPF network element, the other UPF network elements send the multicast data to the gNB;

if the other UPF network elements receive multicast data sent by the gNB directly connected with the other UPF network elements, the other UPF network elements send the multicast data to the root UPF network element;

and if the other UPF network elements receive unicast data sent by the gNB directly connected with the other UPF network elements, the other UPF network elements send the unicast data to the target UPF network elements or the gNB.

In a second aspect, an embodiment of the present application provides a point-to-multipoint data transmission method, including:

receiving a first N4session establishment request message sent by a SMF network element; the first N4session establishment request message contains a first data forwarding rule;

forwarding multicast data according to the first data forwarding rule; the multicast data is point-to-multipoint T2mT data in the air-space-ground integrated network.

Optionally, according to a point-to-multipoint data transmission method of an embodiment of the present application, the forwarding multicast data according to the first data forwarding rule includes:

receiving multicast data sent by a base station gNB directly connected with a root user plane function UPF network element;

and sending the multicast data to other UPF network elements in the multicast group.

receiving multicast data sent by any UPF network element in a multicast group;

and if the UE under the gNB directly connected with the root UPF network element is in a UE list in a multicast group, sending the multicast data to other UPF network elements in the multicast group and the gNB directly connected with the root UPF network element.

In a third aspect, an embodiment of the present application provides a point-to-multipoint data transmission method, including:

receiving a second N4session establishment request message sent by the SMF network element; the second N4session establishment request message includes a second data forwarding rule; the second data forwarding rule is used for indicating a mode of forwarding the multicast data by other UPF network elements in the multicast group; the multicast data is point-to-multipoint T2mT data in the air-space-ground integrated network;

and forwarding the multicast data according to the second data forwarding rule.

Optionally, according to a point-to-multipoint data transmission method of an embodiment of the present application, the forwarding multicast data according to the second data forwarding rule includes:

receiving multicast data sent by a direct-connected base station gNB;

and sending the multicast data to a root User Plane Function (UPF) network element.

receiving multicast data sent by a root UPF network element;

and sending the multicast data to the gNB.

In a fourth aspect, an embodiment of the present application provides a point-to-multipoint data transmission method, including:

receiving multicast data sent by a UPF network element; the multicast data is point-to-multipoint T2mT data in an air-space-ground integrated network;

and if the wireless bearer of the unicast session between the terminal UE and the terminal UE meets the QoS of the multicast session, multiplexing the wireless bearer of the unicast session and sending the multicast data to the UE.

Optionally, according to the point-to-multipoint data transmission method in an embodiment of the present application, after receiving the multicast data sent by the user plane function UPF network element, the method further includes:

and if the radio bearer of the unicast session does not exist between the UE and the UE or the radio bearer of the unicast session does not meet the QoS of the multicast session between the UE and the UE, establishing the radio bearer between the UE and sending the multicast data to the UE.

Optionally, according to the point-to-multipoint data transmission method of an embodiment of the present application, the UPF network element is a root UPF network element.

In a fifth aspect, an embodiment of the present application provides a session management function SMF network element, including a memory, a transceiver, and a processor;

a memory for storing a computer program; a transceiver for transceiving data under control of the processor; a processor for reading the computer program in the memory and performing the following operations:

determining a root User Plane Function (UPF) network element;

Optionally, according to an SMF network element in an embodiment of the present application, the determining a root user plane function UPF network element includes:

Optionally, according to an SMF network element of an embodiment of the present application, the determining a root user plane function UPF network element includes:

Optionally, according to an SMF network element of an embodiment of the present application, the first data forwarding rule includes:

Optionally, according to an SMF network element of an embodiment of the present application, after determining a root user plane function UPF network element, the method further includes:

Optionally, according to an SMF network element of an embodiment of the present application, the second data forwarding rule includes:

In a sixth aspect, an embodiment of the present application provides a user plane function UPF network element, including a memory, a transceiver, and a processor;

Optionally, according to the UPF network element in an embodiment of the present application, the forwarding the multicast data according to the first data forwarding rule includes:

receiving multicast data sent by any UPF network element in a multicast group;

In a seventh aspect, an embodiment of the present application provides a user plane function UPF network element, including a memory, a transceiver, and a processor;

a memory for storing a computer program; a transceiver for transceiving data under control of the processor; a processor for reading the computer program in the memory and performing the following:

receiving a second N4session establishment request message sent by the SMF network element; the second N4session establishment request message includes a second data forwarding rule; the second data forwarding rule is used for indicating a mode of forwarding the multicast data by other UPF network elements in the multicast group; the multicast data is point-to-multipoint T2mT data in an air-space-ground integrated network;

and forwarding the multicast data according to the second data forwarding rule.

Optionally, according to the UPF network element in an embodiment of the present application, the forwarding the multicast data according to the second data forwarding rule includes:

receiving multicast data sent by a base station gNB directly connected;

receiving multicast data sent by a root UPF network element;

and sending the multicast data to the gNB.

In an eighth aspect, an embodiment of the present application provides a base station, including a memory, a transceiver, and a processor;

a memory for storing a computer program; a transceiver for transceiving data under the control of the processor; a processor for reading the computer program in the memory and performing the following operations:

receiving multicast data sent by a UPF network element; the multicast data is point-to-multipoint T2mT data in the air-space-ground integrated network;

Optionally, according to the base station in an embodiment of the present application, after receiving the multicast data sent by the UPF network element, the method further includes:

Optionally, according to the base station of an embodiment of the present application, the UPF network element is a root UPF network element.

In a ninth aspect, an embodiment of the present application provides a point-to-multipoint data transmission apparatus, including:

a determining module, configured to determine a root user plane function UPF network element;

a first sending module, configured to send a first N4session establishment request message to the root UPF network element; the first N4session establishment request message contains a first data forwarding rule; the first data forwarding rule is used for indicating a multicast data forwarding mode of the root UPF network element; the multicast data is point-to-multipoint T2mT data in the air-space-ground integrated network.

In a tenth aspect, an embodiment of the present application provides a point-to-multipoint data transmission apparatus, including:

a first receiving module, configured to receive a first N4session establishment request message sent by a SMF network element; the first N4session establishment request message contains a first data forwarding rule;

the second sending module is used for forwarding the multicast data according to the first data forwarding rule; the multicast data is point-to-multipoint T2mT data in the air-space-ground integrated network.

In an eleventh aspect, an embodiment of the present application provides a point-to-multipoint data transmission apparatus, including:

a second receiving module, configured to receive a second N4session establishment request message sent by the SMF network element; the second N4session establishment request message includes a second data forwarding rule; the second data forwarding rule is used for indicating the mode of forwarding the multicast data by other UPF network elements in the multicast group; the multicast data is point-to-multipoint T2mT data in the air-space-ground integrated network;

and the third sending module is used for forwarding the multicast data according to the second data forwarding rule.

In a twelfth aspect, an embodiment of the present application provides a point-to-multipoint data transmission apparatus, including:

a third receiving module, configured to receive multicast data sent by a user plane function UPF network element; the multicast data is point-to-multipoint T2mT data in an air-space-ground integrated network;

and the fourth sending module is used for multiplexing the radio bearer of the unicast session and sending the multicast data to the UE if the fact that the radio bearer of the unicast session existing between the terminal UE and the terminal UE meets the QoS (quality of service) of the multicast session is determined.

In a thirteenth aspect, the present application further provides a processor-readable storage medium, which stores a computer program, where the computer program is configured to cause the processor to execute the steps of the point-to-multipoint data transmission method according to the first, second, third or fourth aspect.

According to the point-to-multipoint data transmission method, the point-to-multipoint data transmission device, the electronic equipment and the storage medium, the root UPF network element is introduced, the root UPF network element respectively carries out data transmission with other UPFs in the multicast group, a N9 tunnel between the UPF network elements does not need to be reestablished, resources are effectively utilized, and signaling overhead and resource consumption are saved.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings used in the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following descriptions are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative efforts.

Fig. 1 is a schematic diagram illustrating a multicast tunnel establishment process between UPF network elements in an air-space-ground integrated network;

FIG. 2 is a schematic diagram of a process of transmitting T2mT data by using an inter-satellite transmission tunnel in an air-ground integrated network;

fig. 3 is a schematic diagram of a network architecture for point-to-multipoint data transmission provided by an embodiment of the present application;

fig. 4 is a schematic diagram of a point-to-multipoint tunnel establishment process provided in an embodiment of the present application;

fig. 5 is a flowchart illustrating a point-to-multipoint data transmission method according to an embodiment of the present application;

fig. 6 is a second flowchart of a point-to-multipoint data transmission method provided by the embodiment of the present application;

fig. 7 is a data flow diagram of a point-to-multipoint data transmission provided by an embodiment of the application;

fig. 8 is a third flowchart of a point-to-multipoint data transmission method provided in the embodiment of the present application;

fig. 9 is a fourth flowchart of a point-to-multipoint data transmission method according to an embodiment of the present application;

fig. 10 is a schematic structural diagram of an SMF network element provided in an embodiment of the present application;

fig. 11 is a schematic structural diagram of a root UPF network element according to an embodiment of the present application;

fig. 12 is a schematic structural diagram of a UPF network element provided in the embodiment of the application;

fig. 13 is a schematic structural diagram of a base station according to an embodiment of the present application;

fig. 14 is a flowchart of a point-to-multipoint data transmission apparatus according to an embodiment of the present application;

fig. 15 is a second flowchart of a point-to-multipoint data transmission apparatus according to an embodiment of the present application;

fig. 16 is a third schematic flowchart of a point-to-multipoint data transmission apparatus according to an embodiment of the present application;

fig. 17 is a fourth flowchart of a point-to-multipoint data transmission apparatus according to an embodiment of the present application.

Detailed Description

In the existing 5MBS technology, multicast data transmission is performed between a gNB and an UPF network element by establishing a multicast session, and data transmission is performed by establishing a unicast tunnel by establishing a PDU session, where an RB is used between a UE and the gNB for data transmission.

If the existing terrestrial general technology is used to support the T2mT service in the air-space-ground integrated network, when any UE in the multicast group sends a multicast request, tunnels need to be established between the UPF network elements (which may be referred to as "UPF network elements in the multicast group" for short) on the satellite corresponding to the UE in the multicast group, between the UPF network elements and the gNB, and when different UEs in the multicast group send multicast data, if an N9 tunnel is not established between the corresponding UPF network elements, an N9 tunnel between the UPF network elements needs to be re-established, which wastes satellite resources for the satellite of the air-space-ground integrated network.

Fig. 1 is a schematic diagram illustrating a multicast tunnel establishment procedure between UPF network elements in an air-space-ground integrated network, where as shown in fig. 1, after a UE completes group call authorization to a T2mT Service Center (Service Center), it notifies a Session Management Function (SMF network element) to establish a data transmission multicast channel, and a method for establishing a tunnel between adjacent satellite UPF network elements by using the prior art is as follows:

the SMF network element sends a N4Session Establishment Request (N4Session Establishment Request) to a first user plane function UPF1 network element (the UPF1 network element is arranged on a first satellite SAT1), and the UPF1 network element allocates a Tunnel Endpoint Identifier (TEID).

And 2, the UPF1 network element (SAT1) returns an N4Session Establishment Response (N4Session Establishment Response) to the SMF network element, and carries core network Tunnel information (CN Tunnel Info) containing the allocated TEID information.

And 3, the SMF network element sends the N4Session Establishment Request to a second user plane function UPF2 network element (the UPF2 network element is arranged on a second satellite SAT2), and simultaneously carries CN Tunnel Info distributed by the UPF1 network element. The UPF2 network element (SAT2) receives the message and allocates the TEID of the UPF2 network element (SAT 2).

The UPF2 network element (SAT2) returns a N4Session Establishment Response to the SMF network element, carrying the CN Tunnel Info containing the allocated TEID information.

And 5, the SMF network element sends an N4Session Modification Request (N4Session Modification Request) to the UPF1 network element (SAT1), wherein the CN Tunnel Info of the UPF2 network element is carried.

And 6, the UPF1 network element (SAT1) sends a N4Session Modification Response (N4Session Modification Response) to the SMF network element, and the tunnel establishment between the UPF1 network element (SAT1) and the UPF2 network element (SAT2) is completed.

Fig. 2 is a schematic diagram of a process of transmitting T2mT data using an inter-satellite transmission tunnel in an air-ground integrated network, as shown in fig. 2, in the prior art, when a PDU session exists in the network and a gNB and a UE can perform unicast data transmission through an RB, if a multicast transmission tunnel is established, the RB between the gNB and the UE needs to be re-established, that is, when a unicast session and a multicast session exist simultaneously, data transmission between the UE and the gNB is two RBs, which results in resource waste.

In the process of transmitting T2mT data by using an inter-satellite transmission tunnel in the air-space-ground integrated network, when different UEs in a multicast group send multicast data, if an N9 tunnel is not established between corresponding UPF network elements, an N9 tunnel between the UPF network elements needs to be reestablished, which causes resource waste and increases unnecessary signaling overhead.

For example, assume that the UE1 corresponds to a UPF1 network element; the UE2 corresponds to a UPF2 network element; the UE3 corresponds to the UPF network element 3; UE4 corresponds to UPF network element 4. When the UE1 wants to send data to the UE2, the UE3, and the UE4, tunnels are respectively established between the UPF1 network element and the UPF2 network element, between the UPF1 network element and the UPF network element 3, and between the UPF1 network element and the UPF network element 4, so that the purpose of sending data to the UE2, the UE3, and the UE4 by the UE1 can be achieved. However, at this time, if the UE2 wants to send data to the UE3 and the UE4, tunnels need to be established between the UPF2 network element and the UPF network element 3, and between the UPF2 network element and the UPF network element 4 again, which wastes satellite resources.

The embodiment of the application provides a data transmission mode from a terminal to multiple terminals/point to multipoint, which is different from the 'Multicast' concept of the existing Multimedia Broadcast Multicast Service (MBMS). in an air-ground integrated architecture, the satellite does not support T2mT data transmission, and the embodiment of the application introduces a Root UPF network element (Root UPF network element) which respectively performs data transmission with other UPFs in a Multicast group without re-establishing an N9 tunnel between the UPF network elements, thereby effectively utilizing resources, saving signaling overhead and resource consumption, and having important significance for developing satellite Services with relatively deficient resources.

The multicast data in the present application refers to data of T2mT in the air-space-ground integrated network. The multicast group in the present application refers to a group consisting of a plurality of UEs in an air-space-ground integrated network. The gNB corresponding to the UE in the multicast group is called the gNB in the multicast group, and the UPF network element corresponding to the UE in the multicast group is called the UPF network element in the multicast group.

In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

A point-to-multipoint tunnel needs to be established before point-to-multipoint data transmission can take place.

Fig. 3 is a schematic diagram of a network architecture for point-to-multipoint data transmission provided in an embodiment of the present application, and as shown in fig. 3, the network architecture for point-to-multipoint data transmission includes a T2mT service center, a 5G core network (5GC), a gateway station, a root UPF network element, an UPF1 network element, an UPF2 network element, a gNB1, a gNB2, a UE1, a UE2, a UE3, and a UE 4.

The UPF1 network element and the UPF2 network element are both UPF network elements in a multicast group, the gNB1 is a gNB directly connected with the UPF1 network element, the gNB2 is a gNB directly connected with the UPF2 network element, the UE1 and the UE2 access the gNB1, and the UE3 and the UE4 access the gNB 2.

Fig. 4 is a schematic diagram of a point-to-multipoint tunnel establishment procedure provided in an embodiment of the present application, and as shown in fig. 4, a flow of establishing a point-to-multipoint tunnel includes:

1, T2mT Service Center sends request for establishing multicast session to SMF network element, the request message for establishing multicast session carries ID of multicast group and ID List (List) of UE.

And 2, the SMF network element determines a Root UPF network element and a common on-satellite UPF network element.

(1) The SMF network element determines a Root UPF network element.

(2) And the SMF network element determines the UPF network element on the satellite.

The SMF network element selects a Session and Service Continuity Mode (SSCM) and UPF for the established PDU Session.

And 3, the SMF network element sends an N4Session Establishment Request to the Root UPF network element, wherein the Request carries information such as a multicast data forwarding rule, a corresponding multicast group address, a UE ID List and the like of the Root UPF network element.

And the Root UPF network element stores the multicast data forwarding rule and distributes CN tunnel Info of the TEID.

And 4, the Root UPF network element returns N4Session Establishment response to the SMF network element, wherein the response carries CN tunnel Info allocated by the Root UPF network element.

And 5, the SMF network element sends an N4Session Establishment Request to the UPF1 network element, wherein the Request carries information such as a multicast data forwarding rule of the UPF1 network element, a corresponding multicast group address, a UE ID List, and CN tunnel Info of a Root UPF network element.

And 6, the UPF1 network element sends N4Session Establishment response to the SMF network element, wherein the response carries CN tunnel Info allocated by the UPF1 network element. And finishing the multicast tunnel establishment between the Root UPF network element and the UPF1 network element.

And 7, the SMF network element sends an N4Session Establishment Request to the UPF2 network element, wherein the Request carries information such as a multicast data forwarding rule of the UPF2 network element, a corresponding multicast group address, a UE ID List, and CN tunnel Info of the Root UPF network element.

And 8, the UPF2 network element sends N4Session Establishment response to the SMF network element, wherein the response carries CN tunnel Info allocated by the UPF2 network element. And finishing the multicast tunnel establishment between the Root UPF network element and the UPF2 network element.

9. And establishing an N3 tunnel between the gNB1 and the UPF1 network element.

The UPF configures a user plane and informs a Radio Access Network (RAN) of the N3 CN Tunnel Info through AN SMF and AN Access and Mobility Management Function (AMF), the RAN allocates N3 Access network Tunnel information (N3 AN Tunnel Info) and informs the UPF of the information through the AMF and the SMF, and the N3 Tunnel establishment is completed.

The SMF network element sends an N2 message (N2 Info) to the gNB1, where the N2 message carries multicast tunnel information, multicast group address, UE ID List, and Quality of Service (QoS) information of the multicast session between the UPF1 network element and the Root UPF network element.

After receiving the N2 message, the gNB1 determines whether an RB for the established unicast session exists between the gNB1 and the UE.

If the RB of the unicast session is already established between the gNB1 and the UE, the gNB1 determines whether the RB of the unicast session can be reused (or referred to as "multiplexing") according to the QoS of the multicast session, and if the RB of the unicast session can be reused, the gNB1 binds the multicast tunnel and the RB of the unicast session between the established UPF1 network element and the gNB 1.

12. If the RB of the unicast session is not established between the gNB1 and the UE, or the established RB of the unicast session is not reusable, the PDU session establishment process is performed first to complete the establishment of the RB of the unicast session between the gNB1 and the UE, and then the gNB1 binds the established multicast tunnel between the UPF1 network element and the gNB1 to the RB of the unicast session.

13. And establishing an N3 tunnel between the gNB2 and the UPF2 network element, wherein the method refers to the protocol TS 23502.

And 14, the SMF network element sends an N2 message (N2 Info) to the gNB2, wherein the message carries multicast tunnel information, a multicast group address, a UE ID List and Quality of Service (QoS) information of a multicast session between the UPF2 network element and the Root UPF network element.

After receiving the N2 message, the gNB2 determines whether an RB of the established unicast session exists between the gNB2 and the UE.

If the RB of the unicast session has already been established between the gNB2 and the UE, the gNB2 determines whether the RB of the unicast session can be reused (or referred to as "multiplexing") according to the QoS of the multicast session, and if the RB of the unicast session can be reused, the gNB2 binds the multicast tunnel and the RB of the unicast session between the established UPF2 network element and the gNB 2.

16. If the RB of the unicast session is not established between the gNB2 and the UE, or the established RB of the unicast session is not reusable, the PDU session establishment process is performed first to complete the establishment of the RB of the unicast session between the gNB2 and the UE, and then the gNB2 binds the established multicast tunnel between the UPF2 network element and the gNB2 to the RB of the unicast session.

And when the gNB receives the multicast data from the UPF network element, the gNB forwards the multicast data to the corresponding UE through the RB.

Fig. 5 is a flowchart illustrating a point-to-multipoint data transmission method according to an embodiment of the present application, and as shown in fig. 5, an implementation subject of the point-to-multipoint data transmission method according to the embodiment of the present application may be an SMF network element. The method comprises the following steps:

step 501, determining a root User Plane Function (UPF) network element.

Specifically, before point-to-multipoint data transmission, a point-to-multipoint tunnel needs to be established, and a root UPF network element is determined by the SMF network element during establishment of the point-to-multipoint tunnel. The point-to-multipoint tunnel establishment procedure is as described above and will not be described herein.

And the root UPF network element is used for receiving the multicast data and forwarding the multicast data to the UPF network element in the multicast group.

For example, the SMF network element may determine the Root UPF network element according to at least one of the following rules:

a. root UPF network elements are directly connected with all UPF network elements in the multicast group;

b. the Root UPF network element is the UPF network element which contains the most UE in the direct-connected gNB in the multicast group;

c. the Root UPF network element is the UPF network element with the least user plane traffic;

d. the Root UPF network element is one of UPF network elements in the multicast group;

e. the Root UPF network element is a UPF network element outside the multicast group.

Step 502, sending a first N4session establishment request message to the root UPF network element; the first N4session establishment request message contains a first data forwarding rule; the first data forwarding rule is used for indicating a multicast data forwarding mode of the root UPF network element; the multicast data is point-to-multipoint T2mT data in the air-space-ground integrated network.

Specifically, after determining the root UPF network element, the SMF network element sends a first N4session establishment request message to the root UPF network element, where the first N4session establishment request message includes a first data forwarding rule. The first data forwarding rule is used for indicating a mode of forwarding the multicast data by the root UPF network element. The multicast data in the embodiment of the present application may be T2mT data in an air-space-ground integrated network.

And the root UPF network element receives the first N4session establishment request message sent by the SMF network element.

And when multicast data need to be transmitted, the root UPF network element forwards the multicast data according to the first data forwarding rule.

For example, the multicast data forwarding rule of the Root UPF network element may include the following:

if the root UPF network element receives multicast data sent by a gNB directly connected with the root UPF network element, the root UPF network element refers to information such as a multicast group address and a UE ID List, and sends the multicast data to other UPF network elements in the multicast group;

if the root UPF network element receives the multicast data sent by any UPF network element in the multicast group, the root UPF network element refers to the multicast group address, the UE ID List and other information and sends the multicast data to other UPF network elements in the multicast group;

and if the root UPF network element receives the multicast data sent by any UPF network element in the multicast group and the UE under the gNB directly connected with the root UPF network element is in the UE List in the multicast group, the root UPF network element refers to the multicast group address, the UE ID List and other information, and sends the multicast data to other UPF network elements in the multicast group and the gNB directly connected with the root UPF network element.

According to the point-to-multipoint data transmission method provided by the embodiment of the application, the root UPF network element is introduced and performs data transmission with other UPFs in the multicast group respectively, and an N9 tunnel between the UPF network elements does not need to be reestablished, so that resources are effectively utilized, and signaling overhead and resource consumption are saved.

Optionally, the determining a root user plane function UPF network element includes:

Specifically, in the embodiment of the present application, a UPF network element directly connected to all UPF network elements in a multicast group is used as a root UPF network element.

The embodiment of the application can multiplex the established tunnels between the UPF network elements as much as possible, avoids reestablishing the multicast tunnel, and improves the efficiency.

Specifically, in the embodiment of the present application, a UPF network element including the largest number of UEs in a direct connection base station gNB in a multicast group is used as a root UPF network element.

According to the embodiment of the application, when the UE under the gNB directly connected with the root UPF network element needs to send the multicast data, the UE under the gNB directly connected with the non-root UPF network element can directly send the multicast data to other UPF network elements in the multicast group through the root UPF network element, the condition that the UE under the gNB directly connected with the non-root UPF network element sends the multicast data is avoided, the multicast data is sent to the UPF network element firstly, then the UPF network element forwards the root UPF network element, and then the root UPF network element sends the other UPF network elements in the multicast group, the forwarding of data between the UPF network elements is reduced as far as possible, and the efficiency is improved.

Specifically, in the embodiment of the present application, the UPF network element with the minimum user plane traffic is used as the root UPF network element.

The UPF network element with the least user plane flow is used as the root UPF network element, so that the root UPF network element can be ensured to have enough computing resources and storage resources, and the efficiency is improved.

Optionally, the first data forwarding rule includes:

and if the root UPF network element receives multicast data sent by any UPF network element in a multicast group and the UE under the gNB directly connected with the root UPF network element is in a UE list in the multicast group, the root UPF network element sends the multicast data to other UPF network elements in the multicast group and the gNB directly connected with the root UPF network element.

Specifically, in the embodiment of the present application, the multicast data forwarding rule of the root UPF network element includes the following contents:

if the root UPF network element receives multicast data sent by a gNB directly connected with the root UPF network element, the root UPF network element refers to information such as a multicast group address, a UE ID List and the like, and sends the multicast data to other UPF network elements in a multicast group;

According to the embodiment of the application, the root UPF network element and other UPFs in the multicast group respectively carry out data transmission through the defined forwarding rule, an N9 tunnel between the UPF network elements does not need to be reestablished, resources are effectively utilized, and signaling overhead and resource consumption are saved.

Optionally, after determining the root user plane function UPF network element, the method further includes:

Specifically, in this embodiment of the present application, after determining the root UPF network element, the SMF network element further needs to send a second N4session establishment request message to other UPF network elements in the multicast group.

The second N4session establishment request message includes the second data forwarding rule.

And the second data forwarding rule is used for indicating the mode of forwarding the multicast data by other UPF network elements in the multicast group.

For example, the multicast data forwarding rules of other UPF network elements in the multicast group may include the following:

if the other UPF network elements receive the multicast data sent by the root UPF network element, the other UPF network elements refer to the multicast group address, the UE ID List and other information, and send the multicast data to the gNB through the established N3 tunnel;

if other UPF network elements receive the multicast data sent by the gNB directly connected with the other UPF network elements, the other UPF network elements refer to information such as a multicast group address, a UE ID List and the like, and send the multicast data to a root UPF network element through a multicast tunnel;

and if the other UPF network elements receive the unicast data sent by the gNB directly connected with the other UPF network elements, the other UPF network elements send the unicast data to the target UPF network elements or the gNB through the unicast tunnel according to the unicast address.

According to the embodiment of the application, other UPF network elements in the multicast group carry out data forwarding according to the forwarding rule through the defined forwarding rule, so that resources are effectively utilized, and signaling overhead and resource consumption are saved.

Optionally, the second data forwarding rule includes:

Specifically, in this embodiment of the present application, the multicast data forwarding rule of other UPF network elements in the multicast group includes the following contents:

Fig. 6 is a second flowchart of a point-to-multipoint data transmission method provided in the embodiment of the present application, and as shown in fig. 6, the embodiment of the present application provides a point-to-multipoint data transmission method, an execution subject of which may be a root UPF network element. The method comprises the following steps:

step 601, receiving a first N4session establishment request message sent by a session management function SMF network element; the first N4session establishment request message includes a first data forwarding rule.

Specifically, after the SMF network element determines the root UPF network element, the SMF network element sends a first N4session establishment request message to the root UPF network element.

The first N4session establishment request message includes a first data forwarding rule.

The first data forwarding rule is used for indicating a multicast data forwarding mode of the root UPF network element. The multicast data in the embodiment of the present application may be T2mT data in an air-space-ground integrated network.

Step 602, forwarding the multicast data according to the first data forwarding rule; the multicast data is point-to-multipoint T2mT data in the air-space-ground integrated network.

Specifically, after receiving a first N4session establishment request message sent by the SMF network element, the root UPF network element forwards the multicast data according to the first data forwarding rule when the multicast data needs to be transmitted.

Fig. 7 is a data flow diagram of point-to-multipoint data transmission provided in this embodiment of the present application, as shown in fig. 7, an arrow in the diagram indicates a data flow direction, as an example, a UE1 needs to send multicast data, the UE1 first sends the multicast data to a gNB1, then the gNB1 forwards the multicast data to an UPF1 network element, then the UPF1 network element forwards the multicast data to a root UPF network element, and the root UPF network element forwards the multicast data according to a first data forwarding rule.

According to the embodiment of the application, the data forwarding rule sent by the SMF network element is received, so that the root UPF network element respectively carries out data transmission with other UPFs in the multicast group, and an N9 tunnel between the UPF network elements does not need to be reestablished, so that resources are effectively utilized, and signaling overhead and resource consumption are saved.

Optionally, the forwarding multicast data according to the first data forwarding rule includes:

Specifically, in this embodiment, the root UPF network element may receive multicast data sent by a gNB directly connected to the root UPF network element.

And if the root UPF network element receives the multicast data sent by the gNB directly connected with the root UPF network element, the root UPF network element sends the multicast data to other UPF network elements in the multicast group.

For example, in fig. 7, the UE5 has multicast data that needs to be sent, the UE5 sends the multicast data to the gNB3, the gNB3 is a gNB directly connected to the root UPF network element, and the root UPF network element sends the multicast data to other UPF network elements (the UPF1 network element and the UPF2 network element) in the multicast group after receiving the multicast data sent by the gNB 3.

According to the method and the device, the root UPF network element receives the multicast data sent by the gNB directly connected with the root UPF network element and then sends the multicast data to other UPF network elements in the multicast group, so that resources are further effectively utilized, and signaling overhead and resource consumption are saved.

receiving multicast data sent by any UPF network element in a multicast group;

Specifically, in this embodiment of the present application, a root UPF network element may receive multicast data sent by any UPF network element in a multicast group.

And if the root UPF network element receives the multicast data sent by any UPF network element in the multicast group, the root UPF network element sends the multicast data to other UPF network elements in the multicast group.

For example, in fig. 7, a UE1 needs to send multicast data, a UE1 first sends the multicast data to a gNB1, then the gNB1 forwards the multicast data to an UPF1 network element, then an UPF1 network element forwards the multicast data to a root UPF network element, and the root UPF network element receives the multicast data sent by an UPF1 network element in a multicast group and then sends the multicast data to other UPF network elements (an UPF1 network element and an UPF2 network element) in the multicast group.

According to the embodiment of the application, the UPF network element receives the multicast data sent by any UPF network element in the multicast group and then sends the multicast data to other UPF network elements in the multicast group, so that the resources are further effectively utilized, and the signaling overhead and the resource consumption are saved.

receiving multicast data sent by any UPF network element in a multicast group;

And if the UE under the gNB directly connected with the root UPF network element is in the UE list in the multicast group, the root UPF network element sends the multicast data to other UPF network elements in the multicast group and the gNB directly connected with the root UPF network element.

For example, in fig. 7, a UE1 needs to send multicast data, a UE1 first sends the multicast data to a gNB1, then the gNB1 forwards the multicast data to an UPF1 network element, then an UPF1 network element forwards the multicast data to a root UPF network element, and the root UPF network element receives the multicast data sent by an UPF1 network element in a multicast group and then sends the multicast data to other UPF network elements (an UPF1 network element and an UPF2 network element) in the multicast group. The gNB3 is a gNB directly connected to the root UPF network element, the UE5 accesses the gNB3, and if the UE5 is in the UE list in the multicast group, the root UPF network element further needs to send multicast data to the gNB3 directly connected to the root UPF network element.

According to the embodiment of the application, the root UPF network element receives the multicast data sent by any UPF network element in the multicast group, and then sends the multicast data to other UPF network elements in the multicast group and the gNB directly connected with the UPF network elements, so that resources are further effectively utilized, and signaling overhead and resource consumption are saved.

Fig. 8 is a third flowchart of a point-to-multipoint data transmission method provided in the embodiment of the present application, and as shown in fig. 8, an execution subject of the point-to-multipoint data transmission method provided in the embodiment of the present application may be a UPF network element (non-root UPF network element). The method comprises the following steps:

step 801, receiving a second N4session establishment request message sent by a session management function SMF network element; the second N4session establishment request message includes a second data forwarding rule; the second data forwarding rule is used for indicating a mode of forwarding the multicast data by other UPF network elements in the multicast group; the multicast data is point-to-multipoint T2mT data in the air-space-ground integrated network.

Specifically, after the SMF network element determines the root UPF network element, a second N4session establishment request message is sent to the UPF network element.

And the UPF network element receives the second N4session establishment request message sent by the SMF network element.

The second N4session setup request message includes the second data forwarding rule.

And the second data forwarding rule is used for indicating the mode of the UPF network element for forwarding the multicast data. The multicast data in the embodiment of the present application may be T2mT data in an air-to-ground integrated network.

And step 802, forwarding the multicast data according to the second data forwarding rule.

Specifically, after receiving the second N4session establishment request message sent by the SMF network element, the UPF network element forwards the multicast data according to the second data forwarding rule when the multicast data needs to be transmitted.

As shown in fig. 7, a UE1 needs to send multicast data, a UE1 first sends the multicast data to a gNB1, then the gNB1 forwards the multicast data to an UPF1 network element, then the UPF1 network element forwards the multicast data to a root UPF network element, the root UPF network element sends the multicast data to an UPF1 network element and an UPF2 network element according to a first data forwarding rule, and the UPF1 network element and the UPF2 network element forward the multicast data according to a second data forwarding rule after receiving the multicast data.

According to the embodiment of the application, the data forwarding rule sent by the SMF network element is received, so that the UPF network element forwards the multicast data to the root UPF when receiving the multicast data, and the root UPF network element respectively carries out data transmission with other UPFs in the multicast group, and the reestablishment of an N9 tunnel between the UPF network elements is not needed, so that resources are effectively utilized, and the signaling overhead and the resource consumption are saved.

Optionally, the forwarding multicast data according to the second data forwarding rule includes:

receiving multicast data sent by a base station gNB directly connected;

Specifically, in this embodiment of the present application, a UPF network element may receive multicast data sent by a gNB directly connected to the UPF network element.

And after receiving the multicast data sent by the gNB directly connected with the UPF network element, the UPF network element sends the multicast data to the root UPF network element.

For example, in fig. 7, when the UE1 needs to send multicast data, the UE1 first sends the multicast data to the gNB1, where the gNB1 is a gNB directly connected to the UPF1 network element, then the gNB1 forwards the multicast data to the UPF1 network element, and then the UPF1 network element forwards the multicast data to the root UPF network element.

According to the method and the device, the multicast data sent by the gNB directly connected with the UPF network element are received, when the UPF network element receives the multicast data, the multicast data are forwarded to the root UPF, the root UPF network element respectively carries out data transmission with other UPFs in the multicast group, a N9 tunnel between the UPF network elements does not need to be reestablished, resources are effectively utilized, and signaling overhead and resource consumption are saved.

receiving multicast data sent by a root UPF network element;

and sending the multicast data to the gNB.

Specifically, in this embodiment of the present application, the UPF network element may receive multicast data sent by a root UPF network element.

And after receiving the multicast data sent by the root UPF network element, the UPF network element sends the multicast data to the gNB.

For example, in fig. 7, a UE1 needs to send multicast data, a UE1 first sends the multicast data to a gNB1, then the gNB1 forwards the multicast data to an UPF1 network element, then an UPF1 network element forwards the multicast data to a root UPF network element, the root UPF network element receives the multicast data sent by an UPF1 network element in a multicast group, and then sends the multicast data to an UPF1 network element and an UPF2 network element in the multicast group. After receiving the multicast data sent by the root UPF network element, the UPF1 network element forwards the multicast data to the gNB1 directly connected with the UPF network element, and after receiving the multicast data sent by the root UPF network element, the UPF2 network element forwards the multicast data to the gNB2 directly connected with the UPF network element.

According to the method and the device, the multicast data sent by the root UPF network element are received, so that the UPF network element forwards the multicast data to the root UPF when receiving the multicast data, the root UPF network element respectively carries out data transmission with other UPFs in the multicast group, a N9 tunnel between the UPF network elements does not need to be reestablished, resources are effectively utilized, and signaling overhead and resource consumption are saved.

Fig. 9 is a fourth flowchart of the point-to-multipoint data transmission method according to the embodiment of the present application, and as shown in fig. 9, the embodiment of the present application provides a point-to-multipoint data transmission method, an execution subject of which may be a gNB. The method comprises the following steps:

step 901, receiving multicast data sent by a user plane function UPF network element; the multicast data is point-to-multipoint T2mT data in the air-space-ground integrated network.

Specifically, in the embodiment of the present application, after receiving multicast data, no matter a root UPF network element or another UPF network element in a multicast group, if a UE in a coverage area of the root UPF network element is in a UE list in the multicast group, the root UPF network element or another UPF network element in the multicast group needs to forward the multicast data to a gNB directly connected to the root UPF network element.

In the embodiment of the application, the multicast data is point-to-multipoint T2mT data in an air-space-ground integrated network.

And the gNB receives the multicast data sent by the UPF network element.

Step 902, if it is determined that the radio bearer of the unicast session existing between the UE and the terminal UE satisfies the QoS of the multicast session, multiplexing the radio bearer of the unicast session, and sending the multicast data to the UE.

Specifically, in the embodiment of the present application, after receiving multicast data sent by a UPF network element, the gNB determines whether an RB of a unicast session has been established between the gNB and the UE.

If the RB of the unicast session is already established between the gNB and the UE, whether the RB of the unicast session can meet the QoS of the multicast session is further judged.

And if the RB of the unicast session established between the gNB and the UE can meet the QoS of the multicast session, the gNB multiplexes the RB of the unicast session and sends the multicast data to the UE.

If the gbb 2 determines that the RBs of the unicast session established between itself and the UE3 can satisfy the QoS of the multicast session, the gbb 2 multiplexes the RBs of the unicast session and transmits the multicast data to the UE 3.

The embodiment of the application avoids repeatedly establishing the RB by multiplexing the RB of the established unicast session, effectively utilizes resources and saves signaling overhead and resource consumption.

Optionally, after receiving the multicast data sent by the UPF network element, the method further includes:

Specifically, in this embodiment of the present application, if it is determined that there is no radio bearer for the unicast session with the UE or that the radio bearer for the unicast session with the UE does not satisfy the QoS for the multicast session, the gNB establishes a radio bearer with the UE and sends the multicast data to the UE.

If gNB2 determines that the RBs of the unicast session it has established with UE4 cannot satisfy the QoS for the multicast session, gNB2 reestablishes the RBs of the unicast session with UE4 and sends the multicast data to UE4 via the newly established RBs of the unicast session.

According to the embodiment of the application, the new RB is reestablished only when the RB of the unicast session does not exist between the UE or the RB of the unicast session does not meet the QoS of the multicast session between the UE, so that the RB is prevented from being repeatedly established, resources are effectively utilized, and signaling overhead and resource consumption are saved.

Optionally, the UPF network element is a root UPF network element.

Specifically, in this embodiment of the present application, the gNB receives multicast data sent by a root UPF network element. The multicast data is point-to-multipoint T2mT data in the air-space-ground integrated network. The root UPF network element has the same function and function as the root UPF network element described in the foregoing embodiment, and is not described here again.

And if the gNB determines that the radio bearer of the unicast session between the gNB and the UE meets the QoS of the multicast session, multiplexing the radio bearer of the unicast session and sending the multicast data to the UE.

Fig. 10 is a schematic structural diagram of an SMF network element according to an embodiment of the present application, and as shown in fig. 10, the SMF network element includes a memory 1020, a transceiver 1000, and a processor 1010:

a memory 1020 for storing a computer program; a transceiver 1000 for transceiving data under the control of the processor 1010; a processor 1010 for reading the computer program in the memory 1020 and performing the following operations:

determining a root User Plane Function (UPF) network element; sending a first N4session establishment request message to the root UPF network element; the first N4session establishment request message contains a first data forwarding rule; the first data forwarding rule is used for indicating a multicast data forwarding mode of the root UPF network element; the multicast data is point-to-multipoint T2mT data in the air-space-ground integrated network.

And in particular transceiver 1000, for receiving and transmitting data under control of processor 1010.

Where in fig. 10, the bus architecture may include any number of interconnected buses and bridges, with one or more processors represented by processor 1010 and various circuits of memory represented by memory 1020 being linked together. The bus architecture may also link together various other circuits such as peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further herein. The bus interface provides an interface. The transceiver 1000 may be a number of elements including a transmitter and a receiver that provide a means for communicating with various other apparatus over transmission media including wireless channels, wired channels, optical fiber cables, and the like. The user interface 1030 may also be an interface capable of interfacing with a desired device for different user devices, including but not limited to a keypad, display, speaker, microphone, joystick, etc.

The processor 1010 is responsible for managing the bus architecture and general processing, and the memory 1020 may store data used by the processor 1010 in performing operations.

Alternatively, the processor 1010 may be a CPU (central processing unit), an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or a CPLD (Complex Programmable Logic Device), and the processor may also adopt a multi-core architecture.

The processor is used for executing any one of the methods provided by the embodiment of the application according to the obtained executable instructions by calling the computer program stored in the memory. The processor and memory may also be physically separated.

Optionally, the first data forwarding rule includes:

Optionally, the second data forwarding rule includes:

It should be noted that, the SMF network element provided in the embodiment of the present application can implement all the method steps implemented by the method embodiment in which the execution subject is the SMF network element, and can achieve the same technical effects, and detailed descriptions of the same parts and beneficial effects as those in the method embodiment in this embodiment are omitted here.

Fig. 11 is a schematic structural diagram of a root UPF network element according to an embodiment of the present application, and as shown in fig. 11, the root UPF network element includes a memory 1120, a transceiver 1100, and a processor 1110:

a memory 1120 for storing a computer program; a transceiver 1100 for transceiving data under the control of the processor 1110; a processor 1110 for reading the computer program in the memory 1120 and performing the following operations:

And in particular transceiver 1100, for receiving and transmitting data under the control of processor 1110.

In fig. 11, among other things, the bus architecture may include any number of interconnected buses and bridges with various circuits being linked together, particularly one or more processors represented by processor 1110 and memory represented by memory 1120. The bus architecture may also link together various other circuits such as peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further herein. The bus interface provides an interface. The transceiver 1100 may be a plurality of elements including a transmitter and a receiver that provide a means for communicating with various other apparatus over a transmission medium including wireless channels, wired channels, fiber optic cables, and the like. The processor 1110 is responsible for managing the bus architecture and general processing, and the memory 1120 may store data used by the processor 1110 in performing operations.

The processor 1110 may be a Central Processing Unit (CPU), an Application Specific Integrated Circuit (ASIC), a Field-Programmable Gate Array (FPGA), or a Complex Programmable Logic Device (CPLD), and may also have a multi-core architecture.

receiving multicast data sent by any UPF network element in a multicast group;

It should be noted that, the root UPF network element provided in the embodiment of the present application can implement all the method steps implemented by the method embodiment in which the execution main body is the root UPF network element, and can achieve the same technical effect, and detailed descriptions of the same parts and beneficial effects as those of the method embodiment in this embodiment are not repeated here.

Fig. 12 is a schematic structural diagram of a UPF network element according to an embodiment of the present application, and as shown in fig. 12, the UPF network element includes a memory 1220, a transceiver 1200, and a processor 1210:

a memory 1220 for storing computer programs; a transceiver 1200 for transceiving data under the control of the processor 1210; a processor 1210 for reading the computer program in the memory 1220 and performing the following operations:

and forwarding the multicast data according to the second data forwarding rule.

And in particular transceiver 1200, for receiving and transmitting data under control of processor 1210.

Wherein in fig. 12, the bus architecture may include any number of interconnected buses and bridges, with one or more processors, represented by processor 1210, and various circuits, represented by memory 1220, being linked together. The bus architecture may also link together various other circuits such as peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further herein. The bus interface provides an interface. The transceiver 1200 may be a number of elements including a transmitter and a receiver that provide a means for communicating with various other apparatus over a transmission medium including wireless channels, wired channels, fiber optic cables, and the like. The processor 1210 is responsible for managing the bus architecture and general processing, and the memory 1220 may store data used by the processor 1210 in performing operations.

The processor 1210 may be a Central Processing Unit (CPU), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), or a Complex Programmable Logic Device (CPLD), and may also have a multi-core architecture.

receiving multicast data sent by a base station gNB directly connected;

receiving multicast data sent by a root UPF network element;

and sending the multicast data to the gNB.

It should be noted that, the UPF network element provided in the embodiment of the present application can implement all the method steps implemented by the method embodiment in which the execution subject is the UPF network element, and can achieve the same technical effects, and detailed descriptions of the same parts and beneficial effects as those in the method embodiment in this embodiment are omitted here.

Fig. 13 is a schematic structural diagram of a base station according to an embodiment of the present application, and as shown in fig. 13, the base station includes a memory 1320, a transceiver 1300, and a processor 1310:

a memory 1320 for storing computer programs; a transceiver 1300 for transceiving data under the control of the processor 1310; a processor 1310 for reading the computer program in the memory 1320 and performing the following operations:

And more particularly, transceiver 1300 for receiving and transmitting data under the control of processor 1310.

In fig. 13, among other things, the bus architecture may include any number of interconnected buses and bridges with various circuits being linked together, particularly one or more processors represented by processor 1310 and memory represented by memory 1320. The bus architecture may also link together various other circuits such as peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further herein. The bus interface provides an interface. The transceiver 1300 may be a plurality of elements including a transmitter and a receiver that provide a means for communicating with various other apparatus over a transmission medium including wireless channels, wired channels, fiber optic cables, and the like. The processor 1310 is responsible for managing the bus architecture and general processing, and the memory 1320 may store data used by the processor 1310 in performing operations.

The processor 1310 may be a Central Processing Unit (CPU), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), or a Complex Programmable Logic Device (CPLD), and may also have a multi-core architecture.

Optionally, the UPF network element is a root UPF network element

It should be noted that the base station provided in the embodiment of the present application can implement all the method steps implemented by the method embodiment in which the execution subject is the base station, and can achieve the same technical effects, and details of the same parts and beneficial effects as those of the method embodiment in this embodiment are not described herein again.

Fig. 14 is a flowchart of a point-to-multipoint data transmission apparatus provided in an embodiment of the present application, and as shown in fig. 14, the point-to-multipoint data transmission apparatus includes a determining module 1401 and a first sending module 1402, where:

a determining module 1401, configured to determine a root user plane function UPF network element; a first sending module 1402, configured to send a first N4session establishment request message to the root UPF network element; the first N4session establishment request message includes a first data forwarding rule; the first data forwarding rule is used for indicating a multicast data forwarding mode of the root UPF network element; the multicast data is point-to-multipoint T2mT data in the air-space-ground integrated network.

Optionally, the first data forwarding rule includes:

Optionally, the second data forwarding rule includes:

Fig. 15 is a second flowchart of a point-to-multipoint data transmission apparatus according to an embodiment of the present application, and as shown in fig. 15, the point-to-multipoint data transmission apparatus includes a first receiving module 1501 and a second sending module 1502, where:

the first receiving module 1501 is configured to receive a first N4session establishment request message sent by a session management function SMF network element; the first N4session establishment request message includes a first data forwarding rule; the second sending module 1502 is configured to forward the multicast data according to the first data forwarding rule; the multicast data is point-to-multipoint T2mT data in the air-space-ground integrated network.

receiving multicast data sent by any UPF network element in a multicast group;

Fig. 16 is a third schematic flowchart of a point-to-multipoint data transmission apparatus according to an embodiment of the present application, and as shown in fig. 16, the point-to-multipoint data transmission apparatus includes a second receiving module 1601 and a third transmitting module 1602, where:

the second receiving module 1601 is configured to receive a second N4session establishment request message sent by the SMF network element; the second N4session establishment request message includes a second data forwarding rule; the second data forwarding rule is used for indicating a mode of forwarding the multicast data by other UPF network elements in the multicast group; the multicast data is point-to-multipoint T2mT data in an air-space-ground integrated network; the third sending module 1602 is configured to forward the multicast data according to the second data forwarding rule.

receiving multicast data sent by a base station gNB directly connected;

receiving multicast data sent by a root UPF network element;

and sending the multicast data to the gNB.

Fig. 17 is a fourth schematic flowchart of a point-to-multipoint data transmission apparatus according to an embodiment of the present application, and as shown in fig. 17, the point-to-multipoint data transmission apparatus includes a third receiving module 1701 and a fourth sending module 1702, where:

the third receiving module 1701 is configured to receive multicast data sent by a user plane function UPF network element; the multicast data is point-to-multipoint T2mT data in an air-space-ground integrated network; the fourth sending module 1702 is configured to, if it is determined that the radio bearer of the unicast session existing between the UE and the terminal UE meets the QoS of the multicast session, multiplex the radio bearer of the unicast session, and send the multicast data to the UE.

and if the radio bearer of the unicast session does not exist between the UE or the radio bearer of the unicast session does not meet the QoS of the multicast session, establishing the radio bearer between the UE and the UE, and sending the multicast data to the UE.

Optionally, the UPF network element is a root UPF network element

It should be noted that, in the foregoing embodiments of the present application, the division of the units/modules is schematic, and is only one logic function division, and another division manner may be available in actual implementation. In addition, functional units in the embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit may be implemented in the form of hardware, or may also be implemented in the form of a software functional unit.

The integrated unit, if implemented as a software functional unit and sold or used as a stand-alone product, may be stored in a processor readable storage medium. Based on such understanding, the technical solution of the present application may be substantially implemented or contributed by the prior art, or all or part of the technical solution may be embodied in a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, a network device, or the like) or a processor (processor) to execute all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk, an optical disk, or other various media capable of storing program codes.

An embodiment of the present application further provides a processor-readable storage medium, where the processor-readable storage medium stores a computer program, where the computer program is configured to enable the processor to execute the method provided in each of the foregoing embodiments, and the method includes:

Or comprises the following steps:

receiving a first N4session establishment request message sent by a SMF network element; the first N4session establishment request message contains a first data forwarding rule; forwarding multicast data according to the first data forwarding rule; the multicast data is point-to-multipoint T2mT data in the air-space-ground integrated network.

Or comprises the following steps:

receiving a second N4session establishment request message sent by the SMF network element; the second N4session establishment request message includes a second data forwarding rule; the second data forwarding rule is used for indicating the mode of forwarding the multicast data by other UPF network elements in the multicast group; the multicast data is point-to-multipoint T2mT data in an air-space-ground integrated network; and forwarding the multicast data according to the second data forwarding rule.

Or comprises the following steps:

receiving multicast data sent by a UPF network element; the multicast data is point-to-multipoint T2mT data in the air-space-ground integrated network; and if the wireless bearer of the unicast session existing between the terminal UE and the terminal UE is determined to meet the QoS (quality of service) of the multicast session, multiplexing the wireless bearer of the unicast session and sending the multicast data to the UE.

It should be noted that: the processor-readable storage medium can be any available medium or data storage device that can be accessed by a processor, including, but not limited to, magnetic memory (e.g., floppy disks, hard disks, magnetic tape, magneto-optical disks (MOs), etc.), optical memory (e.g., CDs, DVDs, BDs, HVDs, etc.), and semiconductor memory (e.g., ROMs, EPROMs, EEPROMs, non-volatile memory (NAND FLASH), Solid State Disks (SSDs)), etc.

In addition, it should be noted that: in the embodiment of the present application, the term "and/or" describes an association relationship of associated objects, and indicates that three relationships may exist, for example, a and/or B, and may indicate: a exists alone, A and B exist simultaneously, and B exists alone. The character "/" generally indicates that the former and latter associated objects are in an "or" relationship.

In the embodiments of the present application, the term "plurality" means two or more, and other terms are similar thereto.

The technical scheme provided by the embodiment of the application can be suitable for various systems, especially 5G systems. For example, the applicable system may be a global system for mobile communication (GSM) system, a Code Division Multiple Access (CDMA) system, a Wideband Code Division Multiple Access (WCDMA) General Packet Radio Service (GPRS) system, a long term evolution (long term evolution, LTE) system, an LTE Frequency Division Duplex (FDD) system, an LTE Time Division Duplex (TDD) system, an LTE-a (long term evolution) system, a universal mobile system (universal mobile telecommunications system, UMTS), a Worldwide Interoperability for Mobile Access (WiMAX) system, a New Radio network (NR 5) system, etc. These various systems include terminal devices and network devices. The System may further include a core network portion, such as an Evolved Packet System (EPS), a 5G System (5GS), and the like.

The terminal device referred to in the embodiments of the present application may refer to a device providing voice and/or data connectivity to a user, a handheld device having a wireless connection function, or another processing device connected to a wireless modem. In different systems, the names of the terminal devices may be different, for example, in a 5G system, the terminal device may be referred to as a User Equipment (UE). A wireless terminal device, which may be a mobile terminal device such as a mobile telephone (or "cellular" telephone) and a computer having a mobile terminal device, for example, a portable, pocket, hand-held, computer-included, or vehicle-mounted mobile device, may communicate with one or more Core Networks (CNs) via a Radio Access Network (RAN). Examples of such devices include Personal Communication Service (PCS) phones, cordless phones, Session Initiation Protocol (SIP) phones, Wireless Local Loop (WLL) stations, and Personal Digital Assistants (PDAs). The wireless terminal device may also be referred to as a system, a subscriber unit (subscriber unit), a subscriber station (subscriber station), a mobile station (mobile), a remote station (remote station), an access point (access point), a remote terminal device (remote terminal), an access terminal device (access terminal), a user terminal device (user terminal), a user agent (user agent), and a user device (user device), which are not limited in this embodiment of the present application.

The network device according to the embodiment of the present application may be a base station, and the base station may include a plurality of cells for providing services to a terminal. A base station may also be referred to as an access point, or a device in an access network that communicates over the air-interface, through one or more sectors, with wireless terminal devices, or by other names, depending on the particular application. The network device may be configured to exchange received air frames with Internet Protocol (IP) packets as a router between the wireless terminal device and the rest of the access network, which may include an Internet Protocol (IP) communication network. The network device may also coordinate attribute management for the air interface. For example, the network device according to the embodiment of the present application may be a Base Transceiver Station (BTS) in a Global System for Mobile communications (GSM) or a Code Division Multiple Access (CDMA), may also be a network device (NodeB) in a Wideband Code Division Multiple Access (WCDMA), may also be an evolved Node B (eNB or e-NodeB) in a Long Term Evolution (LTE) System, a 5G Base Station (gNB) in a 5G network architecture (next generation System), or may also be a Home evolved Node B (HeNB), a relay Node (relay Node), a Home Base Station (femto), a pico Base Station (pico), which is not limited in the embodiments of the present application. In some network architectures, a network device may include a Centralized Unit (CU) node and a Distributed Unit (DU) node, which may also be geographically separated.

Multiple Input Multiple Output (MIMO) transmission may be performed between the network device and the terminal device by using one or more antennas, where the MIMO transmission may be Single User MIMO (SU-MIMO) or Multi-User MIMO (MU-MIMO). The MIMO transmission may be 2D-MIMO, 3D-MIMO, FD-MIMO, or massive-MIMO, or may be diversity transmission, precoding transmission, beamforming transmission, or the like, depending on the form and number of root antenna combinations.

As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, optical storage, and the like) having computer-usable program code embodied therein.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer-executable instructions. These computer-executable instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These processor-executable instructions may also be stored in a processor-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the processor-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These processor-executable instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present application without departing from the spirit and scope of the application. Thus, if such modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is intended to include such modifications and variations as well.

Claims

1. A method for point-to-multipoint data transmission, comprising:

determining a root User Plane Function (UPF) network element;

2. The method for point-to-multipoint data transmission according to claim 1, wherein the determining a root user plane function, UPF, network element comprises:

3. The method for point-to-multipoint data transmission according to claim 1, wherein the determining a root user plane function, UPF, network element comprises:

4. The point-to-multipoint data transmission method according to claim 1, wherein said determining a root user plane function, UPF, network element comprises:

5. The method for point-to-multipoint data transmission according to claim 1, wherein the first data forwarding rule comprises:

6. The point-to-multipoint data transmission method according to claim 1, wherein after determining a root User Plane Function (UPF) network element, further comprising:

7. The method for point-to-multipoint data transmission according to claim 6, wherein the second data forwarding rule comprises:

8. A method for point-to-multipoint data transmission, comprising:

9. The point-to-multipoint data transmission method of claim 8, wherein forwarding multicast data according to the first data forwarding rule comprises:

10. The point-to-multipoint data transmission method of claim 8, wherein forwarding multicast data according to the first data forwarding rule comprises:

receiving multicast data sent by any UPF network element in a multicast group;

11. The point-to-multipoint data transmission method of claim 8, wherein forwarding multicast data according to the first data forwarding rule comprises:

receiving multicast data sent by any UPF network element in a multicast group;

12. A point-to-multipoint data transmission method, comprising:

and forwarding the multicast data according to the second data forwarding rule.

13. The method for point-to-multipoint data transmission according to claim 12, wherein said forwarding multicast data according to said second data forwarding rule comprises:

receiving multicast data sent by a base station gNB directly connected;

14. The point-to-multipoint data transmission method of claim 12, wherein forwarding multicast data according to the second data forwarding rule comprises:

receiving multicast data sent by a root UPF network element;

and sending the multicast data to the gNB.

15. A point-to-multipoint data transmission method, comprising:

16. The point-to-multipoint data transmission method according to claim 15, wherein after receiving the multicast data sent by the user plane function UPF network element, the method further comprises:

17. The point-to-multipoint data transmission method according to claim 15, wherein the UPF network element is a root UPF network element.

18. A session management function, SMF, network element comprising a memory, a transceiver, a processor;

a memory for storing a computer program; a transceiver for transceiving data under the control of the processor; a processor for reading the computer program in the memory and performing the following:

determining a root User Plane Function (UPF) network element;

19. The SMF network element of claim 18, wherein said determining a root user plane function, UPF, network element comprises:

20. The SMF network element of claim 18, wherein said determining a root user plane function, UPF, network element comprises:

21. The SMF network element of claim 18, wherein said determining a root user plane function, UPF, network element comprises:

22. The SMF network element of claim 18, wherein said first data forwarding rule comprises:

23. The SMF network element of claim 18, wherein after determining a root user plane function, UPF, network element, further comprising:

24. The SMF network element of claim 23, wherein said second data forwarding rule comprises:

25. A User Plane Function (UPF) network element, comprising a memory, a transceiver, a processor;

26. The UPF network element of claim 25, wherein the forwarding multicast data according to the first data forwarding rule comprises:

27. The UPF network element of claim 25, wherein the forwarding multicast data according to the first data forwarding rule comprises:

receiving multicast data sent by any UPF network element in a multicast group;

28. The UPF network element of claim 25, wherein the forwarding multicast data according to the first data forwarding rule comprises:

receiving multicast data sent by any UPF network element in a multicast group;

29. A User Plane Function (UPF) network element, comprising a memory, a transceiver, a processor;

receiving a second N4session establishment request message sent by the SMF network element; the second N4session establishment request message includes a second data forwarding rule; the second data forwarding rule is used for indicating the mode of forwarding the multicast data by other UPF network elements in the multicast group; the multicast data is point-to-multipoint T2mT data in an air-space-ground integrated network;

and forwarding the multicast data according to the second data forwarding rule.

30. The UPF network element of claim 29, wherein the forwarding multicast data according to the second data forwarding rule comprises:

receiving multicast data sent by a direct-connected base station gNB;

31. The UPF network element of claim 29, wherein the forwarding multicast data according to the second data forwarding rule comprises:

receiving multicast data sent by a root UPF network element;

and sending the multicast data to the gNB.

32. A base station comprising a memory, a transceiver, a processor;

and if the wireless bearer of the unicast session existing between the terminal UE and the terminal UE is determined to meet the QoS (quality of service) of the multicast session, multiplexing the wireless bearer of the unicast session and sending the multicast data to the UE.

33. The base station of claim 32, wherein after receiving the multicast data sent by the user plane function UPF network element, the method further comprises:

34. The base station of claim 32, wherein the UPF network element is a root UPF network element.

35. A point-to-multipoint data transmission apparatus, comprising:

36. A point-to-multipoint data transmission apparatus, comprising:

a second sending module, configured to forward multicast data according to the first data forwarding rule; the multicast data is point-to-multipoint T2mT data in the air-space-ground integrated network.

37. A point-to-multipoint data transmission apparatus, comprising:

a second receiving module, configured to receive a second N4session establishment request message sent by the SMF network element; the second N4session establishment request message includes a second data forwarding rule; the second data forwarding rule is used for indicating a mode of forwarding the multicast data by other UPF network elements in the multicast group; the multicast data is point-to-multipoint T2mT data in an air-space-ground integrated network;

38. A point-to-multipoint data transmission apparatus, comprising:

39. A processor-readable storage medium, characterized in that the processor-readable storage medium stores a computer program for causing a processor to perform the method of any one of claims 1 to 17.