WO2021189269A1

WO2021189269A1 - Method and apparatus for implementing service continuity

Info

Publication number: WO2021189269A1
Application number: PCT/CN2020/080978
Authority: WO
Inventors: 许胜锋; 杨艳梅; 李濛
Original assignee: 华为技术有限公司
Priority date: 2020-03-24
Filing date: 2020-03-24
Publication date: 2021-09-30

Abstract

A method and apparatus for implementing service continuity, which may ameliorate the problem of the discontinuity of communication services due to relay UE handover. The method comprises: a session management function network element first receives a first message from a relay user equipment (UE). Since the first message comprises identification information of a remote UE connected to the relay UE, and the relay UE is a UE that is connected to the remote UE after the transmission path of the remote UE is switched, the session management function network element will configure a mapping relationship between a first address and a second address to a user plane function network element, wherein the first address is used for the user plane function network element to transmit data of the remote UE before the transmission path of the remote UE is switched, and the second address is used for the user plane function network element to transmit the data of the remote UE after the transmission path of the remote UE is switched. In the foregoing manner, the continuity of the services may be ensured.

Description

Method and device for realizing business continuity

Technical field

This application relates to the field of communication technology, and in particular to a method and device for realizing business continuity.

Background technique

With the rapid development of mobile communications, the widespread use of new service types, such as video chat, virtual reality (VR) or augmented reality (AR) and other data services, has increased users' demand for bandwidth. Device-to-device (D2D) communication allows direct communication between user equipment (UE), and can share spectrum resources with cell users under the control of the cell network, effectively improving the utilization of spectrum resources . D2D communication includes one-to-many communication and one-to-one communication. One-to-many communication corresponds to multicast and broadcast communication, and one-to-one communication corresponds to unicast communication. In one-to-one communication, if the sender's device and the receiver's device are within close range, they can communicate directly after discovering each other. In D2D communication, UEs communicate through the PC5 interface, which can be used for information transmission on the data plane and the control plane.

As shown in Figure 1, when the UE is out of network coverage or the communication signal between the UE and the access network device is not good, the UE can be assisted by the relay UE, that is, through the communication between the UE and the relay UE, and The communication between the UE and the network-side server is relayed to realize the communication between the UE and the network-side server.

However, when the UE performs auxiliary communication through the relay UE, or the relay UE that the UE is connected to during the auxiliary communication through the relay UE is switched (for example, switching from the first relay UE to the second relay UE, or from The connection relay UE is switched to directly access the access network equipment), the UE will use the new Internet Protocol (IP) address or port to communicate with the network-side server, causing the communication to be interrupted and the continuity of communication services cannot be guaranteed. sex.

Summary of the invention

This application provides a method and device for realizing business continuity, which are used to improve the discontinuity of communication services caused by handover.

In the first aspect, this application provides a method for realizing service continuity. The method can be executed by the internal chip of the session management function network element or the session management function network element. The method is suitable for the scenario where the transmission path of the relay UE is switched. After the transmission path of the remote UE is switched, it accesses the network through the relay UE. In this method, the transmission path of the remote UE is managed by the same SMF network element before and after the handover, and the UPF network element on the transmission path before and after the handover is the same UPF network element. The method includes: the session management function network element receives from the middle Following the UE’s first message, because the first message includes the identification information of the remote UE connected to the relay UE; the session management function network element configures the mapping relationship between the first address and the second address to the user plane function network element, Among them, the first address is used to transmit the data of the remote UE by the user plane function network element before the transmission path of the remote UE is switched, and the second address is used to transmit the data of the user plane function network element to the remote UE after the transmission path of the remote UE is switched. UE's data. In this way, the user plane function network element can transmit data of the remote UE according to the mapping relationship.

Wherein, the address in the embodiment of the present application may be at least one of an address and a port number. For example, the first address may be an IPv4 address+port number; or the first address may be an IPv6 address.

In the embodiment of the present application, after the transmission path of the remote UE is switched, the transport layer connection does not need to be re-established between the remote UE and the network server, and the session management function network element configures the above-mentioned mapping relationship with the user plane function network element, so that The user plane function network element can realize the communication between the remote UE and the network server using the address used before the transmission path switch according to the mapping relationship, that is, through the network side configuration, the remote UE and the network server can be realized between the remote UE and the network server after the transmission path switch. Communication is not interrupted to ensure business continuity.

In a possible embodiment, the first message is used to establish a PDU session of the relay UE, or modify the PDU session of the relay UE, or the first message is a remote UE information report message.

In a possible embodiment, the identification information of the remote UE is used to indicate that the transmission path of the remote UE is switched. Alternatively, the first message carries a first indication, and the first indication is used to indicate that the transmission path of the remote UE is switched. In this way, after the session management function network element receives the first message, it can determine that the transmission path of the remote UE is switched according to the identification information or the first indication of the remote UE in the first message.

In a possible embodiment, the session management function network element determines whether there is a context before the remote UE transmission path switch exists with the remote UE identifier according to the identification information of the remote UE, and if so, the session management function network The meta determines the first address corresponding to the identification information of the remote UE from the context. In another possible embodiment, the first message carries the first address, and the session management function network element obtains the first address from the first message.

It should be noted that if the remote UE accesses network equipment before the transmission path is switched, the remote UE sends the first address to the session management function network element, and the session management function network element stores the first address, so the session The management function network element may obtain the first address from the local storage of the SMF network element.

In a possible embodiment, the session management function network element receives the second address from the relay UE. Wherein, the second address is an address allocated to the remote UE after the relay UE establishes a PDU session.

In a possible embodiment, before the session management function network element receives the second address from the relay UE, it further includes: after the session management function network element receives the PDU session request from the relay UE, the session management function network The meta allocates a third address to the relay UE, and the third address is used for the relay UE to generate the second address.

In a possible embodiment, the session management function network element can send the first address to the relay UE. In this way, the relay UE can configure the mapping relationship between the first address and the second address, and the relay UE can then configure the mapping relationship between the first address and the second address. The mapping relationship transmits the data of the relay UE.

In a possible embodiment, the session management function network element determines that the remote UE has the authority to achieve service continuity according to the identifier of the remote UE. Specifically, the session management function network element may obtain the subscription information of the remote UE from the UDM, and the UDM may obtain the subscription information from the UDR in advance. The subscription information indicates whether the remote UE has service continuity in the relay transmission mode. Permissions. When the SMF network element determines that the remote UE has the service continuity authority according to the subscription information, the mapping relationship between the first address and the second address is configured; otherwise, it is executed according to the prior art.

In a possible embodiment, after the SMF network element releases the PDU session established by the second relay UE, or the second relay UE requests to release the remote UE related context (corresponding to the second relay UE and the remote UE After the PC5 connection is released), the SMF marks the indication information that the first address is released. If the PDU session corresponding to the first relay UE is not released, the SMF network element instructs the first relay UE to reuse the first address.

In the second aspect, this application provides a method for realizing service continuity. The method can be executed by a user plane function network element or an internal chip of a user plane function network element. The method is suitable for a scenario where the transmission path of a relay UE is switched. . In this method, the transmission path of the remote UE is managed by the same SMF network element before and after the handover, and the UPF network elements on the transmission path before and after the handover are the same UPF network element. The method includes: the user plane function network element receives the session The mapping relationship between the first address and the second address of the management function network element, wherein the first address is used for the user plane function network element to transmit the data of the remote UE before the transmission path of the remote user equipment UE is switched, The second address is used for the user plane function network element to transmit the data of the remote UE after the transmission path of the remote UE is switched; the user plane function network element to transmit the data of the remote UE according to the mapping relationship.

For the beneficial effects of the embodiments of the present application, reference may be made to the above-mentioned first aspect, which will not be repeated here.

In a possible embodiment, if the remote UE switches from a direct communication link to a non-direct communication link, the second address is used for the user plane function network element and the second medium after the transmission path of the remote UE is switched. After transmitting the data of the remote UE between the UEs, the second relay UE is the relay UE connected to the remote UE after the transmission path of the remote UE is switched. The first address is used to transmit data of the remote UE between the user plane function network element and the first relay UE before the transmission path of the remote UE is switched. The first relay UE is the remote UE before the transmission path of the remote UE is switched. The relay UE to which the UE is connected; or, the first address is used to transmit data of the remote UE between the user plane function network element and the remote UE before the transmission path of the remote UE is switched.

In a possible embodiment, if the remote UE switches from a non-direct communication link to a direct communication link, the second address is used for the user plane function network after the transmission path of the remote UE is switched. The data of the remote UE is transmitted between the remote UE and the remote UE, and the first address is used to transmit the data between the user plane function network element and the first relay UE before the transmission path of the remote UE is switched. For the data of the remote UE, the first relay UE is the relay UE connected to the remote UE before the remote UE transmission path is switched.

In the third aspect, this application provides a method for realizing service continuity. The method can be executed by the internal chip of the session management function network element or the session management function network element. The method is suitable for the scenario where the transmission path of the relay UE is switched. After the transmission path of the remote UE is switched, it accesses the network through the relay UE. In this method, the transmission path of the remote UE is managed by the same SMF network element before and after the handover, and the UPF network element on the transmission path before and after the handover is the same UPF network element. The method includes: the session management function network element receives from the middle Following the UE’s first message. Since the first message includes the identification information of the remote UE connected to the relay UE, the session management function network element determines the first address according to the identification information of the remote UE, and then the session management function network element sends the first address to the relay UE, Wherein, the first address is used not only for the user plane function network element to transmit the data of the remote UE before the transmission path of the remote UE is switched, but also for the user plane function network element to transmit the data of the remote UE after the transmission path of the end UE is switched. After that, the session management function network element configures the mapping relationship between the first address and the transmission channel to the user plane function network element, and the transmission channel is a transmission channel between the relay UE and the user plane function network element.

In a possible embodiment, the first message is used to establish a PDU session of the relay UE or modify the PDU session of the relay UE. For example, the first message is a PDU session establishment message, or a PDU session modification message, or the first The message is a remote UE information report message.

In a possible embodiment, the identification information of the remote UE is used to indicate that the transmission path of the remote UE is switched. Alternatively, the first message carries a first indication, and the first indication is used to indicate a request to switch the transmission path of the remote UE. In this method, the session management function network element may determine that the transmission path of the remote UE is switched according to the first indication.

In a possible embodiment, the session management function network element determines whether there is a context corresponding to the remote UE identifier according to the identification information of the remote UE. The first address corresponding to the identification information of the end UE. Or in another possible embodiment, the first message includes the first address, and the session management function network element obtains the first address from the first message.

In a possible embodiment, the session management function network element may receive the first address from the remote UE, that is, the remote UE sends the first address to the session management function network element to facilitate the session management function network element Configure the mapping relationship between the first address and the transmission channel.

In a possible embodiment, the session management function network element sends the first address to the relay UE, so that after the relay UE receives the first address, the mapping relationship between the first address and the fourth address can be configured to facilitate The relay UE transmits data of the remote UE, where the fourth address is used to transmit data between the relay UE and the remote UE.

In a possible embodiment, the session management function network element needs to determine whether the remote UE has the authority to achieve service continuity. Specifically, the session management function network element may obtain the subscription information of the remote UE from the UDM, and the UDM may The subscription information is obtained from the UDR in advance, and the subscription information indicates whether the remote UE has service continuity authority in the relay transmission mode. When the SMF network element determines that the remote UE has the service continuity authority according to the subscription information, the mapping relationship between the first address and the second address is configured; otherwise, it is executed according to the prior art.

In a possible embodiment, after the session management function network element releases the PDU session established by the relay UE, or after the relay UE requests to release the related context of the remote UE, the SMF network element will mark that the first address is in a blocked state. In the released state, the session management function network element releases the first address. That is, before the transmission path of the remote UE is switched, the first address is marked as used by the session management function network element, and the session management function network element cannot assign the first address to other remote UEs until the session management function After the network element releases the PDU session established by the relay UE, or after the relay UE requests to release the related context of the remote UE, the session management function network element releases the first address.

In the fourth aspect, the present application provides a method for realizing service continuity, which can be executed by a user plane function network element or an internal chip of a user plane function network element. The method is suitable for a scenario where the transmission path of a relay UE is switched. . In this method, the transmission path of the remote UE is managed by the same SMF network element before and after the handover, and the UPF network elements on the transmission path before and after the handover are the same UPF network element. Combining the method provided by the third aspect, the method includes : The user plane function network element receives the mapping relationship between the first address and the transmission channel from the session management function network element, where the first address is used to transmit remotely to the user plane function network element before the transmission path of the remote user equipment UE is switched. The data of the end UE is also used for the user plane function network element to transmit the data of the remote UE after the transmission path of the remote UE is switched. The transmission channel is the transmission channel between the relay UE and the user plane function network element, and then the user plane function The network element transmits the data of the remote UE according to the mapping relationship.

For the beneficial effects of the embodiments of the present application, reference may be made to the above third aspect, which will not be repeated here.

In a possible embodiment, if the remote UE switches from a non-direct communication link to a non-direct communication link, the first address is used for the user plane function network element and the first medium before the transmission path of the remote UE is switched. After transmitting the data of the remote UE between UEs, the first relay UE is the relay UE connected to the remote UE before the transmission path of the remote UE is switched.

In another possible embodiment, if the remote UE switches from a direct communication link to a non-direct communication link, the first address is used for the user plane function network element and the remote UE before the transmission path of the remote UE is switched. Transfer data between.

In the fifth aspect, the present application provides a method for realizing service continuity. The method can be executed by the relay UE or the internal chip of the relay UE. The method is suitable for a scenario where the transmission path of the relay UE is switched. In this method, the transmission path of the remote UE is managed by the same SMF network element before and after the handover, and the UPF network elements on the transmission path before and after the handover are the same UPF network element. Combining the methods provided by any of the above aspects, this method Including: the relay UE receives the first address from the session management function network element, because the first address is not only used for the user plane function network element to transmit the data of the remote UE before the transmission path of the remote UE is switched, but also used for After the transmission path of the remote UE is switched, the user plane function network element transmits the data of the remote UE, so the relay UE transmits the data of the remote UE according to the mapping relationship between the first address and the fourth address. The four addresses are used to transmit data between the relay UE and the remote UE.

In the implementation of this application, after the transmission path of the remote UE is switched, there is no need to re-establish the transport layer connection between the remote UE and the network server. The session management function network element configures the above-mentioned mapping relationship to the relay UE, so that the relay UE According to this mapping relationship, the remote UE and the network server can communicate with the address used before the transmission path switch, that is, through the network side configuration, the communication between the remote UE and the network server is not interrupted after the transmission path switch, ensuring Business continuity.

In a possible embodiment, before the relay UE receives the first address from the session management function network element, the method includes: the relay UE further receives the identification information of the remote UE from the remote UE, and then the relay UE A first message is sent to the session management function network element, where the first message includes the identification information of the remote UE, so that the session management function network element is used to determine the first address according to the identification information of the remote UE.

In a possible embodiment, the first message is used to establish a PDU session of the relay UE or modify the PDU session of the relay UE. For example, the first message is a PDU session establishment message, or the first message is a PDU session modification request message, or the first message is a remote UE information report message.

In the sixth aspect, the present application provides a method for realizing service continuity. The method can be executed by the internal chip of the session management function network element or the session management function network element. The method is suitable for the scenario where the transmission path of the relay UE is switched. . In this method, the transmission path of the remote UE is managed by the same SMF network element before and after the handover, and the UPF network element on the transmission path before and after the handover is the same UPF network element. Switching to a through communication link, the method includes: the session management function network element receives the identification information of the remote UE from the remote UE and a first indication, the first indication is used to indicate that the transmission path of the remote UE is requested to be switched; The session management function network element sends a fifth address to the remote UE. The fifth address is used to transmit data between the remote UE and the user plane function network element; then the session management function network element configures the fifth address and address to the user plane function network element. The mapping relationship between the first addresses, where the first address is used to transmit the data of the remote UE by the user plane function network element before the transmission path of the remote UE is switched.

In a possible embodiment, the session management function network element may determine the first address according to the identification information of the remote UE, or the session management function network element may receive the first address from the remote UE. For the beneficial effects of the embodiments of the present application, reference may be made to the above aspects, and details are not repeated here.

In the seventh aspect, the present application provides a method for realizing service continuity. The method can be executed by the remote UE or the internal chip of the remote UE. The method is suitable for scenarios where the transmission path of the relay UE is switched. In this method, the transmission path of the remote UE is managed by the same SMF network element before and after the handover, and the UPF network elements on the transmission path before and after the handover are the same UPF network element. Combining the method provided by any one of the above aspects, the method includes :

The remote UE sends the identification information of the remote UE and a first indication to the session management function network element. The first indication is used to indicate a request to switch the transmission path of the remote UE; the remote UE receives the first indication from the session management function network element. Five addresses, the fifth address is used to transmit data between the remote UE and the user plane function network element.

For the beneficial effects of the embodiments of the present application, reference may be made to the above aspects, and details are not repeated here.

In a possible embodiment, the remote UE binds the fifth address with the sixth address, and the sixth address is used to transmit data between the remote UE and the relay UE before the transmission path of the remote UE is switched.

In a possible embodiment, the remote UE may replace the sixth address with the fifth address during the transmission process, where the sixth address is used for the remote UE and the middle UE before the transmission path of the remote UE is switched. Then transfer data between UEs.

In an eighth aspect, the present application provides a method for realizing service continuity. The method can be executed by the internal chip of the session management function network element or the session management function network element. The method is suitable for the scenario where the transmission path of the relay UE is switched. . In this method, the transmission path of the remote UE is managed by the same SMF network element before and after the handover, and the UPF network elements on the transmission path before and after the handover are the same UPF network element. The method includes:

The session management function network element allocates a seventh address to the remote UE, and the seventh address is used to transmit data of the remote UE between the user plane function network element and the server;

The session management function network element configures a first mapping relationship between the seventh address and the first address to the user plane function network element, where the first address is used for transmitting the remote UE on the first transmission path Data, the user plane function network element is a node on the first transmission path;

When the remote UE switches from the first transmission path to the second transmission path, the session management function network element configures the second mapping relationship between the seventh address and the second address to the user plane function network element The second address is used to transmit data of the remote UE on the second transmission path, and the user plane function network element is a node on the second transmission path.

In a possible embodiment, when the remote UE switches from a non-direct communication link to a non-direct communication link, the first address is used to transmit the remote UE between the user plane function network element and the first relay UE. For data, the first relay UE is a node on the first transmission path. The second address is used for transmitting the data of the remote UE between the user plane function network element and the second relay UE, and the second relay UE is a node on the second transmission path.

In a possible embodiment, when the remote UE switches from a non-direct communication link to a direct communication link, the first address is used to transmit data of the remote UE between the user plane function network element and the remote UE. The second address is used to transmit data of the remote UE between the user plane function network element and the remote UE, and the remote UE is a node on the second transmission path.

In a possible embodiment, when the remote UE switches from a non-direct communication link to a direct communication link, the first address is used to transmit data of the remote UE between the user plane function network element and the remote UE. The end UE is a node on the first transmission path, and the second address is used to transmit the data of the remote UE between the user plane function network element and the second relay UE, and the second relay UE is the Node on the second transmission path.

In a ninth aspect, this application provides a method for realizing service continuity. The method can be executed by the internal chip of the first user plane function network element or the first user plane function network element. The method is suitable for relaying the transmission path of the UE. The scene where the switch occurred. In this method, the transmission path of the remote UE is managed by the same SMF network element before and after the handover, and the UPF network elements on the transmission path before and after the handover are different UPF network elements. The method includes: the first user plane function network element receives from A second message of the session management function network element, where the second message includes a first address, and the first address is used for the first user plane function network element to transmit the data of the remote UE before the transmission path of the remote UE is switched; The first user plane function network element transmits the data of the remote UE according to the mapping relationship between the first address and the third transmission channel, where the third transmission channel is the second user plane function network element and the first user plane function network element. The second user plane function network element is the user plane function network element to which the remote UE is connected after the transmission path of the remote UE is switched.

In a possible embodiment, when the remote UE switches from a non-direct communication link to a non-direct communication link, the first address is used for the first user plane function before the transmission path of the remote UE is switched. The data of the remote UE is transmitted between the network element and the first relay UE, and the first relay UE is the relay UE connected to the remote UE before the transmission path of the remote UE is switched. In another possible embodiment, when the remote UE switches from a non-direct communication link to a direct communication link, the first address is used for the first user plane function network element and the remote UE before the transmission path of the remote UE is switched. The data of the remote UE is transmitted between the end UEs.

In a tenth aspect, this application provides a method for realizing service continuity. The method can be executed by the second user plane function network element or the internal chip of the second user plane function network element. The method is suitable for relaying the transmission path of the UE. The scene where the switch occurred. In this method, the transmission path of the remote UE is managed by the same SMF network element before and after the handover, and the UPF network elements on the transmission path before and after the handover are different UPF network elements. The method includes: the second user plane function network element receives from The third message of the session management function network element, the third message includes a first address, and the first address is used for the first user plane function network element to transmit the remote end before the transmission channel of the remote user equipment UE is switched. UE's data;

The second user plane function network element transmits the data of the remote UE according to the mapping relationship between the first address, the second transmission channel, and the third transmission channel, and the second transmission channel is the remote UE The transmission channel between the second user plane and the remote UE after the handover, and the third transmission channel is the transmission channel between the second user plane function network element and the first user plane function network element.

In a possible embodiment, the second user plane function network element receives the first data packet through the second transmission channel, and the first data packet includes the first address; the second user plane function network element receives the first data packet according to the Mapping relationship, sending the first data packet to the first user plane function network element through the third transmission channel.

In a possible embodiment, the second user plane function network element receives a third data packet from the first user plane function network element through a third transmission channel, and the third data packet includes the first address; the second user The surface function network element sends the third data packet through the second transmission channel according to the mapping relationship.

In an eleventh aspect, this application provides a method for realizing service continuity. The method can be executed by the internal chip of the first user plane function network element or the first user plane function network element. The method is suitable for relaying UE transmission. The scenario where the path is switched. In this method, the transmission path of the remote UE is managed by the same SMF network element before and after the handover, and the UPF network elements on the transmission path before and after the handover are different UPF network elements. The method includes:

The first user plane function network element receives a second message from the session management function network element. The second message includes a first address and a second address. The first address is used for the first user plane function before the remote UE's transmission channel is switched. The network element transmits the data of the remote UE, and the second address is used for the second user plane function network element to transmit the data of the remote UE after the transmission path of the remote UE is switched;

The first user plane function network element transmits the data of the remote UE according to the mapping relationship between the first address, the second address and the third transmission channel, where the third transmission channel is the second user plane function network The transmission channel between the element and the first user plane functional network element.

In a possible embodiment, a first user plane function network element receives a first data packet from a second user plane function network element through a third transmission channel, where the first data packet includes the second address; A user plane function network element encapsulates the first data packet with the first address according to the mapping relationship to obtain a second data packet, the second data packet includes the first address; the first user The surface function network element sends a second data packet to the network server.

In a possible embodiment, the first user plane function network element receives a third data packet from the network server, and the third data packet includes the first address; the first user plane function network element In the mapping relationship, the third data packet is encapsulated by using the second address to obtain the encapsulated fourth data packet; the first user plane function network element transmits to the second user plane through the third transmission channel The functional network element sends the fourth data packet.

In the twelfth aspect, this application provides a method for realizing service continuity. The method can be executed by the second user plane function network element or the internal chip of the second user plane function network element. The method is suitable for relaying UE transmission. The scenario where the path is switched. In this method, the transmission path of the remote UE is managed by the same SMF network element before and after the handover, and the UPF network elements on the transmission path before and after the handover are different UPF network elements. The method includes:

The second user plane function network element receives a third message from the session management function network element, the third message includes a second address, and the second address is used to transmit remotely by the second user plane function network element after the transmission channel of the remote UE is switched. Data of the end UE;

The second user plane function network element transmits the data of the remote UE according to the mapping relationship between the second address, the second transmission channel, and the third transmission channel. The second transmission channel is the second user plane after the remote UE is handed over. The third transmission channel is the transmission channel between the second user plane function network element and the first user plane function network element.

In a possible embodiment, the second user plane function network element receives the first data packet through the second transmission channel, and the first data packet includes the first address; the second user plane function network element is based on Mapping relationship, sending the first data packet to the first user plane function network element through a third transmission channel.

In a possible embodiment, the second user plane function network element receives a third data packet from the first user plane function network element through a third transmission channel, and the third data packet includes the first address ; The second user plane function network element sends the third data packet through the second transmission channel according to the mapping relationship.

In the thirteenth aspect, this application provides a method for realizing service continuity. The method can be executed by the second session management function network element or the internal chip of the second session management function network element. The method is suitable for relaying UE transmission. The scenario where the path is switched. In this method, the transmission path of the remote UE is managed by different SMF network elements before and after the handover, and the UPF network elements on the transmission path before and after the handover are different UPF network elements. The method includes:

The second session management function network element receives a first message from a remote user equipment UE, where the first message includes identification information of the remote UE connected to the relay UE;

The second session management function network element configures the mapping relationship between the first address and the second address to the second user plane function network element, wherein the first address is used for the first user before the transmission path of the remote UE is switched The plane function network element transmits the data of the remote UE, and the second address is used for the second user plane function network element to transmit the data of the remote UE after the transmission path of the remote UE is switched;

The second session management function network element requests the first session management function network element to establish a fourth transmission channel, and the first session management function network element serves the remote end before the transmission path of the remote UE is switched. For the session management function network element of the UE, the fourth transmission channel is a transmission channel between the first user plane function network element and the second user plane function network element.

In a possible embodiment, after the context information of the remote UE on the second session management function network element is deleted, the first session management function network element is notified to release the first address.

In a fourteenth aspect, this application provides a method for realizing service continuity. The method can be executed by the internal chip of a unified data management network element or a unified data management network element. This method is suitable for relay UE transmission path switching. Scenes. In this method, the transmission path of the remote UE is managed by different SMF network elements before and after the handover, and the UPF network elements on the transmission path before and after the handover are different UPF network elements. Combining the method shown in the eleventh aspect, the method includes :

The unified data management network element receives the identifier of the remote user equipment UE and the identifier of the first session management function network element from the first session management function network element, and the first session management function network element is a transmission of the remote UE A session management function network element serving the remote UE before path switching;

The unified data management network element receives the identifier of the remote UE from the second session management function network element, and the second session management function network element serves the remote UE after the transmission path of the remote UE is switched Session management function network element;

The unified data management network element sends the identifier of the first session management function network element to the second session management function network element.

In a fifteenth aspect, the present application provides a communication device. The communication device may be a session management function network element or a chip set inside the session management function network element. The communication device is capable of realizing the functions performed by the session management function network element or a chip set inside the session management function network element. For example, the communication device includes performing the first, third, sixth, and third The eighth aspect or the thirteenth aspect relates to the modules or units or means corresponding to the steps. The functions or units or means can be realized by software, or by hardware, or by hardware executing corresponding software.

In a possible design, the communication device includes a processing unit and a communication unit. The communication unit can be used to send and receive signals to achieve communication between the communication device and other devices. For example, the communication unit is used to receive Relay the first message of the UE; the processing unit may be used to perform some internal operations of the communication device. The functions performed by the processing unit and the communication unit may correspond to the steps involved in the above-mentioned various aspects of the session management function network element.

In a possible design, the communication device includes a processor, and may also include a transceiver. The transceiver is used to send and receive signals, and the processor executes program instructions to complete any possible design or implementation of the above aspects. The method in the way. Wherein, the communication device may further include one or more memories, and the memories are used for coupling with the processor. The one or more memories may be integrated with the processor, or may be provided separately from the processor, which is not limited in this application. The memory can store necessary computer programs or instructions to realize the functions involved in the above-mentioned various aspects. The processor can execute the computer program or instruction stored in the memory, and when the computer program or instruction is executed, the communication device realizes any possible design or implementation manner involved in the above-mentioned session management function network element. In the method.

In a possible design, the communication device includes a processor and a memory, and the memory can store necessary computer programs or instructions for realizing the functions involved in the first aspect. The processor can execute the computer program or instruction stored in the memory, and when the computer program or instruction is executed, the communication device realizes any possible design or implementation manner involved in the above-mentioned session management function network element. In the method.

In a possible design, the communication device includes at least one processor and an interface circuit, where at least one processor is used to communicate with other devices through the interface circuit and execute any possible design or implementation of the above aspects In the method executed by the session management function network element.

In a sixteenth aspect, the present application provides a communication device. The communication device may be a user plane functional network element or a chip set inside the user plane functional network element. The communication device is capable of realizing the functions performed by the user plane function network element or a chip set inside the user plane function network element. For example, the communication device includes modules or modules corresponding to the steps involved in the second and fourth aspects. Units or means, the functions or units or means can be realized by software, or by hardware, or by hardware executing corresponding software.

In a possible design, the communication device includes a processing unit and a communication unit. The communication unit can be used to send and receive signals to achieve communication between the communication device and other devices. For example, the communication unit is used to receive The configuration message of the session management function network element; the processing unit can be used to perform some internal operations of the communication device. The functions performed by the processing unit and the communication unit may correspond to the steps involved in the above aspects.

In a possible design, the communication device includes a processor, and may also include a transceiver. The transceiver is used to send and receive signals, and the processor executes program instructions to complete any possible design or implementation of the above aspects. The method in the way. Wherein, the communication device may further include one or more memories, and the memories are used for coupling with the processor. The one or more memories may be integrated with the processor, or may be provided separately from the processor, which is not limited in this application. The memory can store necessary computer programs or instructions to realize the functions involved in the above-mentioned various aspects. The processor can execute the computer program or instruction stored in the memory, and when the computer program or instruction is executed, the communication device realizes the method in any possible design or implementation manner of the above-mentioned user plane function network element .

In a possible design, the communication device includes a processor and a memory, and the memory can store necessary computer programs or instructions for implementing the functions involved in the above aspects. The processor can execute the computer program or instruction stored in the memory, and when the computer program or instruction is executed, the communication device realizes the method in any possible design or implementation manner of the foregoing aspects.

In a possible design, the communication device includes at least one processor and an interface circuit, where at least one processor is used to communicate with other devices through the interface circuit and execute any possible network element of the user plane function described above. The method in the design or implementation.

In a possible design, the communication device may include a first communication device and a second communication device, and the first communication device is a first user plane function network element or a chip and a second communication device set inside the first user plane function network element. The second communication device is a second user plane function network element or a chip set inside the second user plane function network element, and the first communication device is equipped to implement the above-mentioned first user plane function network element or is set in the first user plane function network element. The function performed by the chip inside the element, for example, the communication device includes the module or unit or means corresponding to the steps involved in the ninth aspect and the eleventh aspect. The function or unit or means can be implemented by software, or by Hardware implementation can also be implemented by hardware executing corresponding software. The second communication device is capable of realizing the functions performed by the second user plane function network element or a chip set inside the second user plane function network element. For example, the communication device includes performing the tenth aspect and the twelfth aspect. Related to the modules or units or means corresponding to the steps, the functions or units or means can be realized by software, or by hardware, or by hardware executing corresponding software.

In a seventeenth aspect, the present application provides a communication device. The communication device may be a relay UE or a chip set inside the relay UE. The communication device has a function to implement the above-mentioned relay UE or a chip set inside the relay UE. For example, the communication device includes a module or unit or means corresponding to the steps involved in the fifth aspect. The function or The unit or means can be realized by software, or by hardware, or by hardware executing corresponding software.

In a possible design, the communication device includes a processor, and may also include a transceiver. The transceiver is used to send and receive signals, and the processor executes program instructions to complete any possible design or implementation of the above aspects. The method in the way. Wherein, the communication device may further include one or more memories, and the memories are used for coupling with the processor. The one or more memories may be integrated with the processor, or may be provided separately from the processor, which is not limited in this application. The memory can store necessary computer programs or instructions to realize the functions involved in the above-mentioned various aspects. The processor can execute the computer program or instruction stored in the memory, and when the computer program or instruction is executed, the communication device realizes the method in any possible design or implementation manner of the above-mentioned relay UE aspect.

In a possible design, the communication device includes at least one processor and an interface circuit, where at least one processor is used to communicate with other devices through the interface circuit, and execute any possible design or design in the aspect of relaying UE described above. The method in the implementation mode.

In an eighteenth aspect, the present application provides a communication device. The communication device may be a remote UE or a chip set inside the remote UE. The communication device is capable of implementing functions performed by the remote UE or a chip set inside the remote UE. For example, the communication device includes modules or units or means corresponding to the steps involved in the seventh aspect. The functions or The unit or means can be realized by software, or by hardware, or by hardware executing corresponding software.

In a possible design, the communication device includes a processor, and may also include a transceiver. The transceiver is used to send and receive signals, and the processor executes program instructions to complete any possible design or implementation of the above aspects. The method in the way. Wherein, the communication device may further include one or more memories, and the memories are used for coupling with the processor. The one or more memories may be integrated with the processor, or may be provided separately from the processor, which is not limited in this application. The memory can store necessary computer programs or instructions to realize the functions involved in the above-mentioned various aspects. The processor can execute the computer program or instruction stored in the memory, and when the computer program or instruction is executed, the communication device implements any possible design or implementation method of the remote UE.

In a possible design, the communication device includes at least one processor and an interface circuit, where at least one processor is used to communicate with other devices through the interface circuit and execute any possible design or design of the remote UE described above. The method in the implementation mode.

In an eighteenth aspect, the present application provides a communication device. The communication device may be a unified data management network element or a chip set inside the unified data management network element. The communication device has a function to implement the above-mentioned unified data management network element or a chip set inside the unified data management network element. For example, the communication device includes a module or unit or means corresponding to the steps involved in the fourteenth aspect. The functions, units, or means can be realized by software, or by hardware, and can also be realized by hardware executing corresponding software.

In a possible design, the communication device includes a processor, and may also include a transceiver. The transceiver is used to send and receive signals, and the processor executes program instructions to complete any possible design or implementation of the above aspects. The method in the way. Wherein, the communication device may further include one or more memories, and the memories are used for coupling with the processor. The one or more memories may be integrated with the processor, or may be provided separately from the processor, which is not limited in this application. The memory can store necessary computer programs or instructions to realize the functions involved in the above-mentioned various aspects. The processor can execute the computer program or instruction stored in the memory, and when the computer program or instruction is executed, the communication device realizes the method in any possible design or implementation of the unified data management network element. .

In a possible design, the communication device includes at least one processor and an interface circuit, where at least one processor is used to communicate with other devices through the interface circuit and execute any possible aspect of the unified data management network element described above. The method in the design or implementation.

In a nineteenth aspect, this application provides a computer-readable storage medium in which computer-readable instructions are stored. When the computer reads and executes the computer-readable instructions, the computer is allowed to execute the various aspects described above. Any possible design method.

In a twentieth aspect, this application provides a computer program product, which when a computer reads and executes the computer program product, causes the computer to execute any one of the possible design methods in the above-mentioned various aspects.

In a twenty-first aspect, an embodiment of the present application provides a communication system, which includes a session management function network element and a user plane function network element, where;

The session management function network element may be used to execute the first aspect or any one of the methods in the first aspect.

The user plane function network element may be used to execute the second aspect or any one of the methods in the second aspect.

In a twenty-second aspect, an embodiment of the present application provides a communication system, which includes a session management function network element, a user plane function network element, and a relay UE, where:

The session management function network element may be used to execute the third aspect or any one of the methods in the third aspect.

The user plane function network element may be used to execute any one of the foregoing fourth aspect or the fourth aspect.

The relay UE may be used to execute any one of the above-mentioned fifth aspect or the fifth aspect.

In a twenty-third aspect, an embodiment of the present application provides a communication system, which includes a session management function network element and a remote UE, where:

The session management function network element may be used to execute any one of the above-mentioned sixth aspect or the sixth aspect.

The remote UE may be used to execute any method in the seventh aspect or the seventh aspect described above.

In a twenty-fourth aspect, an embodiment of the present application provides a communication system, which includes a first user plane function network element and a second user plane function network element, where;

The first user plane function network element may be used to execute any one of the aforementioned ninth aspect or the ninth aspect.

The second user plane function network element may be used to execute any one of the tenth aspect or the tenth aspect described above.

In a twenty-fifth aspect, an embodiment of the present application provides a communication system, which includes a first user plane function network element and a second user plane function network element, wherein:

The first user plane function network element may be used to execute any one of the above-mentioned eleventh aspect or the eleventh aspect.

The second user plane function network element may be used to execute any one of the above-mentioned twelfth aspect or the twelfth aspect.

In a twenty-sixth aspect, an embodiment of the present application provides a communication system, which includes a second session management function network element and a unified data management network element, where:

The second session management function network element may be used to execute any one of the above-mentioned thirteenth aspect or the thirteenth aspect.

The unified data management network element may be used to execute any one of the fourteenth aspect or the fourteenth aspect described above.

In a twenty-seventh aspect, the present application provides a chip that includes a processor, and the processor is coupled with a memory, and is configured to read and execute a software program stored in the memory to implement any of the above aspects. A possible design approach.

These and other aspects of the application will be more concise and understandable in the description of the following embodiments.

Description of the drawings

Fig. 1 is a schematic diagram of a communication scenario provided by the prior art;

FIG. 2 is a schematic diagram of the architecture of a communication system provided by an embodiment of this application;

3A to 3C are schematic diagrams of an application communication scenario provided by an embodiment of this application;

FIG. 4 is a schematic flowchart of the first method for realizing business continuity provided by an embodiment of this application;

FIG. 5A is a schematic flowchart of another method for realizing business continuity provided by an embodiment of this application;

FIG. 5B is a schematic diagram of an application communication scenario provided by an embodiment of this application;

FIG. 6 is a schematic flowchart of a second method for realizing business continuity provided by an embodiment of this application;

FIG. 7A is a schematic flowchart of another method for realizing business continuity provided by an embodiment of the application;

FIG. 7B is a schematic diagram of an application communication scenario provided by an embodiment of this application;

FIG. 8 is a schematic flowchart of a third method for realizing business continuity provided by an embodiment of this application;

FIG. 9A is a schematic flowchart of another method for realizing business continuity provided by an embodiment of this application;

FIG. 9B is a schematic diagram of an application communication scenario provided by an embodiment of this application;

FIG. 10A is a schematic flowchart of a fourth method for realizing business continuity provided by an embodiment of this application; FIG.

FIG. 10B is a schematic diagram of an application communication scenario provided by an embodiment of this application;

FIG. 10C is a schematic diagram of an application communication scenario provided by an embodiment of this application;

FIG. 11A is a schematic flowchart of a fifth method for realizing business continuity provided by an embodiment of this application; FIG.

FIG. 11B is a schematic diagram of an application communication scenario provided by an embodiment of this application;

FIG. 12A is a schematic flowchart of a fifth method for realizing business continuity according to an embodiment of this application;

FIG. 12B is a schematic diagram of an application communication scenario provided by an embodiment of this application;

FIG. 12C is a schematic diagram of an application communication scenario provided by an embodiment of this application;

FIG. 13A is a schematic flowchart of a fifth method for realizing business continuity according to an embodiment of this application;

FIG. 13B is a schematic diagram of an application communication scenario provided by an embodiment of this application;

FIG. 14 is a possible exemplary block diagram of a device involved in an embodiment of this application;

FIG. 15 is a schematic structural diagram of a terminal device provided by an embodiment of this application;

FIG. 16 is a schematic structural diagram of a network device provided by an embodiment of this application.

Detailed ways

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

Hereinafter, some terms in the embodiments of the present application will be explained to facilitate the understanding of those skilled in the art.

1) Terminal equipment (terminal equipment), also known as terminal, user equipment (UE), mobile station (MS), mobile terminal (MT), etc., is a way of providing voice to users And/or data connectivity devices, for example, may include a handheld device with a wireless connection function, or a processing device connected to a wireless modem.

The terminal can communicate with the core network via a radio access network (RAN), and exchange voice and/or data with the RAN. The terminal may include user equipment (UE), wireless terminal, mobile terminal, subscriber unit (subscriber unit), subscriber station (subscriber station), mobile station (mobile station), remote station (remote station), access Point (access point, AP), remote terminal (remote terminal), access terminal (access terminal), user terminal (user terminal), user agent (user agent), or user equipment (user device), etc. In the embodiments of the present application, a remote UE (remote UE) may be connected to the network through an access network device, or may be connected to the network through a relay UE (relay UE).

For example, it may include mobile phones (or "cellular" phones), computers with mobile terminals, portable, pocket-sized, handheld, computer-built or vehicle-mounted mobile devices, smart wearable devices, and so on. For example, personal communication service (PCS) phones, cordless phones, session initiation protocol (SIP) phones, wireless local loop (WLL) stations, personal digital assistants, PDA), and other equipment.

Alternatively, the terminal device may also include restricted devices, such as devices with low power consumption, or devices with limited storage capabilities, or devices with limited computing capabilities. Examples include barcodes, radio frequency identification (RFID), sensors, global positioning system (GPS), laser scanners and other information sensing equipment.

As an example and not a limitation, in the embodiments of this application, smart wearable devices are the general term for using wearable technology to intelligently design daily wear and develop wearable devices, such as glasses, gloves, watches, clothing and shoes Wait. A smart wearable device is a portable device that is directly worn on the body or integrated into the user's clothes or accessories.

Smart wearable devices are not only a hardware device, but also realize powerful functions through software support, data interaction, and cloud interaction. Broadly speaking, smart wearable devices include full-featured, large-sized, complete or partial functions that can be achieved without relying on smart phones, such as smart watches or smart glasses, etc., and only focus on a certain type of application function, and need to cooperate with other devices such as smart phones. Use, such as all kinds of smart bracelets, smart helmets, smart jewelry, etc. for physical sign monitoring.

Alternatively, the terminal may also be a virtual reality (VR) device, an augmented reality (AR) device, a wireless terminal in industrial control, a wireless terminal in driverless, and a remote Wireless terminal in remote medical surgery, wireless terminal in smart grid, wireless terminal in transportation safety, wireless terminal in smart city, smart home ) In the wireless terminal, etc.

2) (Radio) access network ((radio) access network, (R) AN) equipment, for example, includes a base station (e.g., access point), which may refer to the radio access network through one or more cells on the air interface. Terminal communication equipment. The (wireless) access network equipment can be used to convert received air frames and Internet Protocol (IP) packets to each other, as a router between the remote UE and the rest of the access network, where the rest of the access network can be Including IP networks. The (wireless) access network equipment can also coordinate the attribute management of the air interface.

For example, (wireless) access network equipment may include radio network controller (RNC), node B (Node B, NB), base station controller (BSC), and base transceiver station (base transceiver station). , BTS), home base station (for example, home evolved NodeB, or home Node B, HNB), baseband unit (BBU), or wireless fidelity (Wi-Fi) access point (access point, AP) and so on.

The (wireless) access network equipment may also include a long term evolution (LTE) system or an evolved LTE system (LTE-Advanced, LTE-A) or the 4th generation mobile communication technology (4G) ) Evolved base station (NodeB or eNB or e-NodeB, evolutional Node B) in the system.

Alternatively, the (wireless) access network equipment may also include the next generation node B (gNB) and the transmission and reception point (TRP) in the 5G system or the new radio (NR) system, Or transmission point (TP).

Alternatively, the (wireless) access network equipment may also include a centralized unit (CU) and/or a distributed unit (DU) in a cloud radio access network (CloudRAN) system, The embodiments of the application are not limited. In the embodiments of the present application, the technical terms "(wireless) access network equipment" and "access network equipment" can be used interchangeably.

3) The core network (CN) equipment is connected to multiple access networks, including the circuit switched (CS) domain and/or the data switching (Packet Switched, PS) domain. The CS network element has a mobile switching center , Visit location register and gateway mobile switching center, PS network element has general packet radio service (general packet radio service, GPRS) node and gateway GPRS support node. Some network elements such as home location register, visitor location register, authentication center can be shared by CS domain and PS domain.

4) In the embodiments of the present application, "multiple" refers to two or more than two. In view of this, "multiple" can also be understood as "at least two" in the embodiments of the present application. "At least one" can be understood as one or more, for example, one, two or more.

For example, including at least one refers to including one, two or more, and does not limit which ones are included. For example, including at least one of A, B, and C, then the included can be A, B, C, A and B, A and C, B and C, or A and B and C.

"And/or" describes the association relationship of the associated objects, indicating that there can be three types of relationships, for example, A and/or B, which can mean: A alone exists, A and B exist at the same time, and B exists alone.

In addition, the character "/", unless otherwise specified, generally indicates that the associated objects before and after are in an "or" relationship. The terms "system" and "network" in the embodiments of this application can be used interchangeably.

Unless otherwise stated, ordinal numbers such as “first” and “second” mentioned in the embodiments of the present application are used to distinguish multiple objects, and are not used to limit the order, timing, priority, or importance of multiple objects.

Some concepts related to the embodiments of the present application are introduced as above, and the technical features of the embodiments of the present application are introduced below.

In view of this, the embodiments of the present application provide a method for realizing service continuity. In this method, the session management function network element configures the transmission path to the UPF network element before and after the UPF network element transmits the data of the remote UE. The mapping relationship between the address and the second address enables the UPF network element to implement communication between the remote UE and the network server using the address used before the transmission path switch based on the mapping relationship, thereby ensuring the continuity of the service of the remote UE .

Among them, the method and the device are based on the same inventive concept. Since the principles of the method and the device to solve the problem are similar, the implementation of the device and the method can be referred to each other, and the repetition will not be repeated. In the description of the embodiments of the present application, “and/or” describes the association relationship of the associated objects, indicating that there can be three types of relationships, for example, A and/or B, which can mean: A alone exists, and both A and B exist separately. There are three cases of B. The character "/" generally indicates that the associated objects before and after are in an "or" relationship. At least one involved in this application refers to one or more; multiple refers to two or more. In addition, it should be understood that, in the embodiments of the present application, both the core network device and the access network device may be referred to as network devices. In the description of this application, for the convenience of explanation, the embodiments of this application may use words such as "first" and "second" to distinguish the description. It is understandable that such words cannot be understood as indicating or implying relative importance. Nor can it be understood as indicating or implying order.

The technical solutions of the embodiments of this application can be applied to various communication systems, such as long term evolution (LTE) systems, worldwide interoperability for microwave access (WiMAX) communication systems, and the fifth generation (5th generation). Generation, 5G) communication systems, such as new radio access technology (NR) and future communication systems, such as 6G systems. Specifically, for example, it can be applied to machine type communication (MTC) communication scenarios, and it can also be applied to cellular-based narrowband internet of things (NB-IoT) communication scenarios, or It is applied to any downlink small data packet transmission scenario.

The embodiments of the present application will be described in detail below in conjunction with the accompanying drawings.

FIG. 2 is a schematic diagram of the architecture of a possible communication system to which the embodiments of this application are applicable. As shown in Figure 2, the unified communication system architecture is also divided into two parts: the wireless access network and the core network. The radio access network is the next generation radio access network (NG-RAN), which is used to implement functions related to radio access. The core network includes: access and mobility management function (AMF) network elements, session management function (SMF) network elements, user plane function (UPF) network elements, unified Data management (unified data management, UDM) network elements, etc. Among them, the AMF network element is mainly responsible for mobility management. AMF network elements may also be called AMF devices or AMF entities. The SMF network element is mainly responsible for session management. The SMF network element may also be referred to as an SMF device or an SMF entity. The UPF network element is mainly responsible for processing user messages, such as forwarding. The UE can access the DN by establishing a session from the UE to the NG-RAN to the UPF to the data network (DN). The UDM network element is mainly used to store the subscription information of the remote UE.

It should be understood that the communication system architecture provided by the embodiments of the present application is only an example, which can be applied to 5G systems, advanced long term evolution (LTE-A) systems, and worldwide microwave interconnection access (worldwide interoperability). for microwave access, WiMAX), or wireless local area networks (WLAN) systems, etc.

In addition, the communication system architecture may also be suitable for future-oriented communication technologies. The communication system architecture described in the embodiments of the present application is intended to more clearly illustrate the technical solutions of the embodiments of the present application, and does not constitute a reference to the embodiments of the present application. As for the limitation of technical solutions, those of ordinary skill in the art will know that with the evolution of the network architecture, the technical solutions provided in the embodiments of the present application are equally applicable to similar technical problems.

For ease of description, take the method applied to the communication system architecture shown in FIG. 2 as an example. In the following description, the interactive equipment may include remote UE, relay UE, RAN, SMF, UPF, UDM, and so on.

The embodiment of the application provides a method for realizing service continuity. The method can be applied to a scenario where a remote UE switches from directly accessing the RAN to a scenario where the remote UE accesses the RAN through a relay UE, as shown in FIG. 3A. When the communication signal between the remote UE and the RAN is not good, the remote UE switches from directly accessing the RAN to accessing the RAN through the relay UE, that is, switching from the direct communication link to the non-direct communication link. In this way, after the transmission path is switched, the remote UE can transmit the uplink and downlink data with the network server through the transmission path between the relay UE and the UPF. In this scenario, transmission path switching refers to: the remote UE switches from the first transmission path that uses its own PDU session to connect to the network, and switches to the second transmission path that the remote UE connects to the network by relaying the UE’s PDU session. path.

Alternatively, the method provided in the embodiments of the present application can be applied to a scenario where the remote UE switches from accessing the first relay UE to the remote UE accessing the second relay UE. As shown in FIG. 3B, in this scenario, when When the location of the remote UE moves or the communication signal between the remote UE and the first relay UE is not good, the remote UE switches from connecting to the first relay UE to connecting to the second relay UE, that is, from the first non-direct connection The communication link is switched to the second non-direct communication link. In this way, after the transmission path is switched, the remote UE can transmit the uplink and downlink data with the network server through the transmission path between the second relay UE and the UPF. In this scenario, transmission path switching refers to: the remote UE connects to the first transmission path of the network from the PDU session established by the first relay UE to the remote UE through the PDU session connection of the second relay UE. The second transmission path to the network.

Alternatively, the method provided in the embodiments of the present application can be applied to a scenario where a remote UE switches from an access relay UE to a remote UE directly accessing the RAN. As shown in FIG. 3C, in this scenario, when the remote UE is When the communication signal between the UEs is not good, the remote UE switches to directly access the RAN, that is, switches from a non-direct communication link to a direct communication link. In this way, after the transmission path is switched, the remote UE can transmit the uplink and downlink data with the network server through the direct communication link. In this scenario, transmission path switching refers to: the remote UE connects to the first transmission path of the network from the PDU session established by the relay UE, and switches to the second transmission path that the remote UE connects to the network through the PDU session established by itself. Transmission path.

It should be noted that, in this application, the direct communication link refers to: a remote UE establishes a PDU session, and the remote UE uses its own PDU session to connect to the network. The non-direct communication link refers to: the relay UE establishes a PDU session, and the remote UE connects to the network through the PDU session of the relay UE.

The following describes the technical solutions provided by the embodiments of the present application in conjunction with the accompanying drawings.

Example one

Refer to Figure 4, which is a schematic flow chart of the first method for realizing service continuity provided by the embodiment of this application. In this method, the transmission path of the remote UE is managed by the same SMF network element before and after the handover, and before and after the handover The UPF network elements on the transmission path are the same UPF network element, and the method includes the following steps.

Step 401: The remote UE switches to the relay UE, and connects to the network through the relay UE. The remote UE can establish a PC5 communication link with the relay UE, and the remote UE will use the fourth address for communication in the PC5 communication link. (Assuming that it is represented by IP3), it is notified to the relay UE.

Exemplarily, as shown in FIG. 3A, the remote UE switches from directly accessing the RAN to accessing the RAN through the relay UE, that is, switching from the direct communication link to the non-direct communication link, before the remote transmission path is switched In the direct communication link, the address used by the remote UE to send data is the first address, that is, the address used by the remote UE before the transmission path is switched is the first address, and the remote UE communicates with the relay UE after the transmission path is switched. The address used is the fourth address.

Or, as shown in FIG. 3B, the remote UE switches from accessing the first relay UE to accessing the second relay UE, that is, switches from the first non-direct communication link to the second non-direct communication link, and the remote In the first non-direct communication link before the transmission path switch of the remote end, the address used by the remote UE to send data to the first relay UE is also the fourth address, that is, the remote UE and the first intermediate link before the transmission path switch After the address used for UE communication is the fourth address, the address used for communication between the remote UE and the second relay UE is still the fourth address after the transmission path is switched.

Step 402: The relay UE sends the first message to the SMF network element.

Wherein, the first message may be a PDU session establishment message or a PDU session modification request message. If the first message is a PDU session establishment message, after the relay UE establishes the PDU session, the remote UE is assigned a second address (assumed to be represented by IP2-1). In addition, the first message may also be a remote user report (remote user report) message.

Exemplarily, with reference to FIG. 3B, the remote UE is handed over from the first relay UE to the second relay UE, and the remote UE sends a relay access request message to the second relay UE. The message includes at least the remote UE. The identification information of the end UE (for example, the remote UE ID). The identification information of the remote UE may also be used to indicate that the transmission path of the remote UE is switched, so that the SMF network element can determine that the transmission path of the remote UE is switched.

In a possible embodiment, the first message may also include a first indication, such as a transmission path switching indication (path switching indication), where the first indication is used to indicate a request to switch the transmission path of the remote UE. Exemplarily, with reference to FIG. 3B, the remote UE switches from the first relay UE to the second relay UE, the remote UE sends a relay access request message to the second relay UE, and the second relay UE After receiving the relay access request message, the second relay UE sends a session establishment message or a PDU session modification request message to the SMF network element, and the message carries the identification information of the remote UE and the first indication. So that the SMF network element determines that the transmission path of the remote UE is switched according to the first indication.

Step 403: The SMF network element determines the first address and the second address corresponding to the identifier of the remote UE.

The first address refers to the address used by the UPF network element to transmit the data of the remote UE before the remote UE is switched. The second address refers to the address used by the UPF network element to transmit the data of the remote UE after the transmission path is switched.

It should be noted that the address in the embodiment of the present application may be at least one of an address and a port number. For example, the first address may be an IPv4 address+port number; or the first address may be an IPv6 address.

Exemplarily, with reference to FIG. 3A, the first address refers to the address used by the remote UE in the communication link before the transmission path switch, the address is configured by the SMF network element for the remote UE, and the second address refers to It is the address configured by the relay UE for the remote UE after the PDU session is established in the communication link after the transmission path is switched. With reference to Figure 3B, the first address refers to the address configured by the first relay UE for the remote UE after the PDU session is established in the communication link before the transmission path switch, and the second address refers to the transmission path switch In the subsequent communication link, the second relay UE configures the address for the remote UE after establishing the PDU session.

For the first address, specifically, the SMF network element may use any one or more of the following methods to determine the first address.

Manner 1: The SMF network element can obtain the context information of the remote UE before the transmission path switching from the UDM or from the local storage of the SMF network element according to the identification information of the remote UE, and then determine the first address from the context.

Manner 2: The first message also includes the first address. Alternatively, the relay UE sends a second message to the SMF network element, where the second message includes the first address. Wherein, the first address is obtained by the relay UE from the remote UE. If the communication link of the remote UE is as shown in Figure 3A before the transmission path is switched, the first address can be obtained by the remote UE from SMF; if the communication link of the remote UE is as shown in the figure before the transmission path is switched As shown in 3B, the first address may be obtained by the remote UE from the first relay UE.

For the second address, specifically, the SMF network element obtains the second address from the relay UE. Exemplarily, with reference to FIG. 3A, the method includes: after the remote UE sends a relay access request message to the relay UE, the relay UE establishes a PDU session, and the SMF network element configures a third address for the relay UE ( For example, it is represented by IP2), and the relay UE configures a second address for the remote UE (for example, it is represented by IP2-1). After that, the relay UE may also send a third message to the SMF network element, where the third message includes the second address. In this way, the SMF network element can obtain the second address from the relay UE.

In a possible embodiment, the method further includes step 404. After receiving the first message, the SMF determines whether the remote UE has the authority to achieve service continuity, and if so, continues to perform the subsequent steps, otherwise, Do not execute.

Specifically, the SMF network element may obtain the subscription information of the remote UE from the UDM, and the UDM may obtain the subscription information from the UDR in advance. The subscription information indicates whether the remote UE has service continuity authority in the relay transmission mode. When the SMF network element determines that the remote UE has the service continuity authority according to the subscription information, the subsequent steps are executed, otherwise, it is executed according to the prior art.

It should be noted that the subscription information may indicate that the remote UE corresponding to the identification information of the remote UE has service continuity authority, but the remote UE may have multiple corresponding addresses, so the SMF network element cannot determine which address has the service. Continuity authority. In this way, the remote UE also needs to send a message including the first address to the SMF network element, so that the SMF can determine that the first address has the authority for business continuity.

Step 405: The relay UE configures the mapping relationship between the second address and the fourth address, and uses the mapping relationship to transmit uplink and downlink data of the remote UE.

Specifically, for uplink transmission, the remote UE sends uplink data to the relay UE, the relay UE receives a first data packet from the remote UE, the first data packet includes a fourth address, and the relay UE according to the second address The mapping relationship between the fourth address and the second address is used to encapsulate the first data packet to obtain the encapsulated second data packet, and then the second data packet is sent to the network side. For downlink transmission, after the relay UE receives the third data packet from the network side, the third data packet includes the second address, and the relay UE uses the fourth address pair according to the mapping relationship between the second address and the fourth address. The third data packet is encapsulated to obtain the encapsulated fourth data packet, and then the fourth data packet is sent to the remote UE.

Step 406: The SMF network element sends a configuration message to the UPF network element, where the configuration message includes the mapping relationship between the first address and the second address.

It should be noted that there is no timing relationship between step 405 and step 406. Step 405 can be performed first, and then step 406, or step 406 can be performed first, and then step 405 can be performed, or step 405 and step 406 can be performed at the same time. The application is not limited.

Step 407: The UPF network element transmits the data of the remote UE according to the mapping relationship.

Specifically, for uplink transmission, the remote UE sends uplink data to the relay UE, the UPF network element receives the first data packet from the relay UE, the first data packet includes the second address, and the UPF network element Encapsulate the first data packet with the first address to obtain the encapsulated second data packet, and then send the second data packet to the network server. In this way, before and after the transmission path of the remote UE is switched, the mapping relationship is Configuration, there is no need to re-establish the transport layer connection between the remote UE and the network server, so that the communication between the remote UE and the network server is not interrupted after the transmission path is switched, ensuring business continuity.

For downlink transmission, the UPF network element receives the third data packet from the network server. The third data packet includes the first address. The UPF network element uses the second address to encapsulate the third data packet according to the mapping relationship. Then the fourth data packet is sent to the relay UE. In this way, before and after the transmission path of the remote UE is switched, through the configuration of the above mapping relationship, the remote UE and the network server do not need to be re-established The transmission layer connection realizes the uninterrupted communication between the remote UE and the network server after the transmission path is switched, ensuring business continuity.

The above method will be further described with an example in combination with the scenario shown in FIG. 3B below. Specifically, this example includes the following steps, as shown in FIG. 5A.

In step 500, before the remote UE switches the transmission path, the remote UE connects to the network through the first relay UE, the SMF network element allocates an address (for example, represented by IP1) to the first relay UE, and the first relay UE is in communication with the After the UPF network element establishes the transmission channel, it allocates a first address (for example, represented by IP1-1) to the remote UE. The SMF network element can record the association relationship between the identity of the first relay UE, the PDU session identifier, DNN, S-NSSAI, IP1, the identification information of the remote UE, and the first address. The association relationship can be stored in the UDR or UDM middle. The SMF network element may also obtain the association relationship from the UDR or UDM.

It should be noted that, in a possible embodiment, after the SMF network element configures the first address for the remote UE (for example, IP1-1 in Figure 5B), the SMF network element records "IP1-1 is in use "" and can be stored in the context of the PDU session before the transmission path, that is, the first address has not been released, and the SMF network element cannot allocate the first address to other remote UEs.

Step 501: When the remote UE finds that the communication quality of the current non-direct communication link is poor or degraded, and cannot meet the current service requirements, the remote UE performs relay reselection, finds the second relay UE, and communicates with the second intermediate UE. Then the UE establishes a PC5 link; the remote UE notifies the fourth address (assumed to be represented by IP3) corresponding to the PC5 link to the second relay UE.

Step 502: The remote UE sends a relay connection request message to the second relay UE, where the relay connection request message may include remote terminal identification information.

In a possible embodiment, the relay connection request message may further include a first indication, such as a transmission path switching indication (path switching indication), so that the network device can determine that the transmission path of the remote UE is switched. Optionally, when the service continuity mode (service continuity mode) subscribed by the remote UE is service continuity, the relay connection request message includes the transmission path switch indication (that is, the remote UE can request the network Guarantee business continuity).

Optionally, if the remote UE has already sent the identification information of the remote UE to the second relay UE when establishing the PC5 communication connection with the second relay UE, the relay connection request message may not carry the remote end Identification information of the UE.

Optionally, the second relay UE separately sends a message requesting identification information, and the remote UE returns the identification information of the remote UE.

Step 503: The second relay UE initiates a PDU session establishment message or a PDU session modification request message to the AMF network element. The message includes the identifier of the remote UE and the transmission path switching instruction.

It should be noted that if an existing PDU session can support the session requirement of the remote UE, the second relay UE initiates a PDU session modification request message; if no PDU session can support the session requirement of the remote UE, the second relay UE The relay UE initiates a PDU session establishment request message.

Optionally, the message may also be a remote UE information report (remote UE Report) message sent after the PDU session is established.

Optionally, the second relay UE may first establish a PDU session (a PDU session dedicated to a non-direct communication link, and the remote UE information is not included in the session context), and then perform step 503 to modify the session (report the remote UE information) .

Step 504: The AMF network element forwards the identification information (or the first indication) of the remote UE in the message to the SMF network element.

In step 505, the SMF network element may determine whether the transmission path of the remote UE is switched according to the identification information of the remote UE, or the SMF network element may determine whether the transmission path of the remote UE is switched according to the first indication.

Specifically, the way for the SMF network element to determine whether the transmission path of the remote UE is switched may be: Method 1, the SMF network element determines according to the first indication (for example, path switching indication), and if the SMF network element receives the first indication, it determines The transmission path of the remote UE is switched; otherwise, the transmission path does not switch.

Method 2: The SMF network element determines whether the corresponding context of the remote UE already exists, that is, whether the remote UE already has a PDU session associated with the PDU session attributes of the second relay UE, such as DNN, S-NSSAI, that is, The remote UE requests a PDU session with the same session attribute for data transmission. If it exists, it is determined that the transmission path of the remote UE is switched; otherwise, the transmission path is not switched.

It should be noted that, if the SMF network element judges according to the second method, the above-mentioned steps 502 to 504 do not need to include the first instruction.

Step 506: After determining that the transmission path of the remote UE is switched, the SMF network element further obtains the subscription information of the remote UE from the UDM, and the subscription information indicates whether the remote UE has the authority of business continuity. If it is, the SMF network element continues to execute the subsequent steps, otherwise, it executes in the existing manner.

Optionally, when the SMF network element determines that the transmission path of the remote UE is switched, the SMF network element releases the PDU session of the first relay UE, but marks that the first address (for example, IP1-1 in FIG. 5B) is in use Status, that is, the SMF network element temporarily does not allocate the first address to other remote UEs.

Step 507: The SMF network element determines the first address used by the non-direct communication link before the transmission path of the remote UE is switched (ie, IP1-1 in FIG. 5B), and determines the non-direct communication after the transmission path of the remote UE is switched. The second address used by the communication link (ie, IP2-1 in Figure 5B).

With regard to the first address, specifically, the SMF network element may adopt any one of the method 1 or the method 2 in step 403 to determine the first address. For details, please refer to the above step 403, which will not be repeated here.

Specifically, the SMF network element may obtain the second address from the second relay UE. That is, after the remote UE switches and connects to the second relay UE, the second relay UE establishes a PDU session, and the SMF network element configures a third address (for example, represented by IP2) for the second relay UE. Subsequently, the UE configures a second address (ie, IP2-1 in FIG. 5B) for the remote UE. After that, the second relay UE may also send a third message to the SMF network element, where the third message includes the second address. In this way, the SMF network element can obtain the second address from the second relay UE.

Step 508: The SMF network element sends a configuration message to the UPF network element. The configuration message includes the mapping relationship between the first address and the second address. The configuration message is used to instruct the UPF network element to convert the first address in the downlink data to The second address, and the second address in the uplink data is converted into the first address.

Step 509: The second relay UE determines the first mapping relationship between the second address (that is, IP2-1 in FIG. 5B) and the fourth address corresponding to the PC5 link (that is, IP3 in FIG. 5B), and the second address and A second mapping relationship between the PDU sessions established by the second relay UE, where the first mapping relationship and the second mapping relationship are used to forward uplink and downlink data of the remote UE.

In step 510, the UPF network element is configured with a mapping relationship between the first address and the second address, and an association relationship between the first address and the PDU session established by the second relay UE is also established.

With reference to Figure 5B, after the second relay UE and the UPF network element complete the above configuration, for the uplink transmission data, the second relay UE converts the IP 3 address in the data packet from the remote UE to the IP 2-1 address , And then transmit through the PDU session established by the second relay UE. After the UPF network element receives the data packet through the session, it uses IP1-1 to encapsulate the first data packet received from the relay UE to obtain the encapsulated second data packet, and then send the second data packet to the network Server, in this way, for the network server, before and after the transmission path of the remote UE is switched, the remote UE uses the same IP1-1 to communicate with the network side server, so service continuity can be guaranteed. For the downstream transmission data, the UPF network element receives the third data packet from the network server, converts the IP 1-1 address in the data packet to the IP 2-1 address for re-encapsulation, obtains the encapsulated fourth data packet, and then Four data packets are sent to the second relay UE. The second relay UE re-encapsulates the data packet using IP3 and forwards the data packet to the remote UE. In this way, for the remote UE, the remote UE Before and after the transmission path is switched, the remote UE uses the same IP3 address to communicate with the second relay UE, so service continuity can be guaranteed.

It should be noted that when the SMF network element releases the PDU session established by the second relay UE, or the second relay UE requests to release the remote UE related context (corresponding to the PC5 connection between the second relay UE and the remote UE) After the release), the SMF network element marks the first address in the released state. That is, the first address is released, and the SMF network element can allocate the first address to other remote UEs.

In the embodiment of this application, after the transmission path of the remote UE is switched, there is no need to re-establish the transport layer connection between the remote UE and the network server. The SMF network element configures the UPF network element with one of the above-mentioned first address and second address. And the mapping relationship between the second address and the fourth address configured by the SMF network element to the connected relay UE after the handover, so that the UPF network element can use the mapping relationship between the remote UE and the network server The address used before the transmission path switch is used for communication, that is, through the network side configuration, the communication between the remote UE and the network server is not interrupted after the transmission path is switched, and service continuity is ensured.

Example two

Refer to Figure 6, which is a schematic flow diagram of the second method for realizing service continuity provided by the embodiment of this application. In this method, the transmission path of the remote UE is managed by the same SMF network element before and after the handover, and before and after the handover The UPF network elements on the transmission path are the same UPF network element, and the method includes the following steps.

Step 601 and step 602 are the same as step 401 and step 402 described above.

Before step 601, that is, before the transmission path is switched, the SMF also allocates a seventh address to the remote UE, and configures the mapping relationship between the seventh address and the first address to the UPF.

Step 603: The SMF network element determines the mapping relationship between the seventh address and the second address corresponding to the identifier of the remote UE.

The first address refers to the address used by the UPF network element to transmit data of the remote UE before the remote UE is switched. The second address refers to the address used by the UPF network element to transmit the data of the remote UE after the remote UE is switched. Exemplarily, with reference to FIG. 3A, the first address refers to the IP address used by the remote UE to transmit data in the direct communication link before the transmission path is switched, and the second address refers to the IP address after the transmission path is switched. The IP address used for data transmission between the remote UE and the UPF network element in the non-direct communication link; with reference to Figure 7B, the first address refers to the remote end of the non-direct communication link before the transmission path is switched The address IP1-1 used for data transmission between the UE and the UPF network element. The second address refers to the address used for data transmission between the remote UE and the UPF network element in the non-direct communication link after the transmission path is switched. IP2-1 used. In addition, for the specific method for determining the first address and the second address, refer to the above step 403, which will not be repeated here.

In addition, the seventh address refers to that the SMF network element allocates an address visible to the network server side for the remote UE, and the seventh address is used to transmit data of the remote UE between the UPF network element and the network server side. The SMF network element may determine the seventh address according to the identity of the remote UE. Exemplarily, with reference to FIG. 7B, the seventh address refers to the IP7 allocated by the SMF network element to the remote UE, and the IP7 is visible to the network server side.

Step 604 is the same as the above step 404, and step 605 is the same as the above step 405.

Step 606: The SMF network element sends a configuration message to the UPF network element. The configuration message includes the mapping relationship between the second address and the seventh address.

Step 607: The UPF network element transmits the data of the remote UE according to the mapping relationship between the second address and the seventh address.

Specifically, for uplink transmission, the remote UE sends uplink data to the relay UE, the UPF network element receives the first data packet from the relay UE, the first data packet includes the second address, and the UPF network element , Use the seventh address to encapsulate the first data packet to obtain the encapsulated second data packet, and then send the second data packet to the network server. In this way, for the network server, before and after the transmission path of the remote UE is switched Through the configuration of the above mapping relationship, the remote UE and the network server do not need to re-establish the transport layer connection, so that the communication between the remote UE and the network server is not interrupted after the transmission path is switched, and the business continuity is ensured.

For downlink transmission, the UPF network element receives the third data packet from the network server. The third data packet includes the seventh address. The UPF network element uses the second address to encapsulate the third data packet according to the mapping relationship. Then send the fourth data packet to the relay UE. In this way, for the remote UE, through the above mapping relationship configuration, the remote UE and the network server do not need to re-establish the transport layer connection , To realize the uninterrupted communication between the remote UE and the network server after the transmission path is switched, ensuring business continuity.

The above method will be further described with an example in combination with the scenario shown in FIG. 3B below. Specifically, this example includes the following steps, as shown in FIG. 7A.

Step 700a is the same as step 500 described above.

Step 700b: After obtaining the address information of the remote UE (IP1-1 in FIG. 7B), the SMF network element allocates a seventh address (IP7 in FIG. 7B) to the remote UE. The seventh address is used for The data of the remote UE is transmitted between the UPF network element and the network server.

Step 700c: The SMF network element configures the mapping relationship between the first address and the seventh address to the UPF network element.

Steps 701 to 707 are the same as the above steps 501 to 507.

In step 708, the SMF network element configures the mapping relationship between the second address (IP2-1 in FIG. 7B) and the seventh address (IP7 in FIG. 7B) to the UPF network element.

Step 709: The second relay UE determines the mapping relationship between the second address and the fourth address (IP3 in FIG. 7B), and uses the mapping relationship to transmit data of the remote UE.

Step 710: The UPF network element configures a mapping relationship between the second address and the seventh address, and uses the mapping relationship to transmit data of the remote UE.

With reference to Figure 7B, after the second relay UE and the UPF network element have completed the configuration of the above mapping relationship, for the uplink transmission data, the second relay UE detects the data packet containing IP3 from the remote UE, and then transfers the data The IP3 after the packet is converted to IP2-1, and the converted data packet is mapped to the PDU session of the second relay UE for transmission. The UPF network element detects that the received data packet contains IP2-1, and then the data packet After that, IP2-1 is converted to IP7, and the converted data packet is sent to the network server. For downlink transmission data, when the UPF network element detects a data packet containing IP7 from the network server, it converts the IP7 of the data packet to IP2-1 and maps it to the PDU session established by the UPF network element for transmission. The second relay UE converts IP2-1 in the data packet received from the UPF network element to IP3, and sends the converted data packet to the remote UE.

In the embodiment of this application, after the transmission path of the remote UE is switched, there is no need to re-establish the transport layer connection between the remote UE and the network server. The SMF network element configures the UPF network element with one of the seventh address and the second address. According to the mapping relationship between the UPF network element, the remote UE and the network server can communicate with the remote UE and the network server using the address used before the transmission path switch, that is, through the network side configuration, the remote UE and the network server can be The communication between network servers is not interrupted to ensure business continuity.

Example three

Refer to Figure 8 for a schematic flow chart of the third method for realizing service continuity provided by the embodiment of this application. In this method, the transmission path of the remote UE is managed by the same SMF network element before and after the handover, and before and after the handover The UPF network elements on the transmission path are the same UPF network element, and the method includes the following steps.

Step 801, the remote UE switches to the relay UE, connects to the network through the relay UE, and establishes a PC5 link with the relay UE; the remote UE will use the fourth address for communication in the PC5 communication link (assuming IP3 Means) notify the relay UE.

Exemplarily, as shown in FIG. 3A, the remote UE switches from directly accessing the RAN to accessing the RAN through a relay UE, that is, switching from a direct communication link to a non-direct communication link, or, as shown in FIG. 3B, The remote UE switches from accessing the first relay UE to accessing the second relay UE, that is, switches from the first non-direct communication link to the second non-direct communication link.

Step 802: When the relay UE requests to establish a PDU session, the relay UE sends a first message to the SMF network element. The first message includes the identification information of the remote UE.

Exemplarily, with reference to FIG. 3B, the remote UE is handed over from the first relay UE to the second relay UE, and the remote UE sends a relay access request message to the second relay UE. The message includes at least the remote UE. Identification information of the end UE (remote UE ID). The identification information of the remote UE may also be used to indicate that the transmission path of the remote UE is switched, so that the SMF network element can determine that the transmission path of the remote UE is switched.

In a possible embodiment, the relay connection request message may further include a first indication, where the first indication is used to indicate a request to switch the transmission path of the remote UE, for example, a transmission path switch indication (path switch indication), so that The network device determines that the transmission path of the remote UE is switched. Optionally, when the service continuity mode (service continuity mode) subscribed by the remote UE is service continuity, the relay connection request message includes the transmission path switch indication (that is, the remote UE can request the network Guarantee business continuity). Exemplarily, with reference to FIG. 3B, the remote UE switches from the first relay UE to the second relay UE, the remote UE sends a relay access request message to the second relay UE, and the second relay UE After receiving the relay access request message, the second relay UE sends a session establishment message or a PDU session modification request message to the SMF network element, and the message carries the identification information of the remote UE and the first indication. So that the SMF network element determines that the transmission path of the remote UE is switched according to the first indication.

Step 803: The SMF network element determines the first address used by the communication link of the remote UE before the transmission path is switched.

The first address refers to the address used by the UPF network element to transmit the data of the remote UE before the remote UE is switched. The first address may refer to at least one of an IP address and a port number. Among them, the specific method for determining the first address can refer to the method one and the method two shown in step 403 in the first embodiment, which will not be repeated here.

In a possible embodiment, the method further includes step 804. After receiving the first message, the SMF determines whether the remote UE has the authority to achieve business continuity, and if so, continues to perform the subsequent steps, otherwise, Do not execute.

For the specific method for determining whether the remote UE has the authority to achieve service continuity, refer to step 404 in the above-mentioned embodiment 1, which will not be repeated here.

Step 805: The SMF network element sends the first address to the relay UE.

Step 806: The relay UE receives the first address from the SMF network element, configures the mapping relationship between the first address and the fourth address, and uses the mapping relationship to transmit uplink and downlink data of the remote UE. The relay UE also needs to configure the mapping relationship between the first address and the transmission channel established by the relay UE.

Optionally, the relay UE obtains the first address from the remote UE. Correspondingly, the remote UE can obtain the first address from the connected relay UE before the path switch, or the remote UE itself knows the first address when the remote UE is directly connected before the path switch. Specifically, for uplink transmission, the remote UE sends uplink data to the relay UE, the relay UE receives a first data packet from the remote UE, the first data packet includes a fourth address, and the relay UE according to the first address The mapping relationship between the fourth address and the first address is used to encapsulate the first data packet to obtain the encapsulated second data packet, and then the second data packet is sent to the network side through the established transmission channel. For downlink transmission, after the relay UE receives the third data packet from the network side, the third data packet includes the first address, and the relay UE uses the fourth address pair according to the mapping relationship between the first address and the fourth address. The third data packet is encapsulated to obtain the encapsulated fourth data packet, and then the fourth data packet is sent to the remote UE.

Step 807: The SMF network element sends a configuration message to the UPF network element, where the configuration message is used to configure the mapping relationship between the first address and the transmission channel established by the relay UE.

Specifically, the configuration message may include a mapping relationship between the first address and the tunnel endpoint identifier corresponding to the PDU session established by the relay UE. That is, the transmission channel established by the relay UE in step 807 may refer to the PDU session established by the relay UE.

It should be noted that there is no time sequence relationship between step 806 and step 807. Step 806 can be executed first, and then step 807 can be executed, or step 807 can be executed first, and then step 806 can be executed, or step 806 and step 807 can be executed at the same time. The application is not limited.

Step 808: The UPF network element transmits the uplink and downlink data between the network server and the remote UE according to the mapping relationship between the first address and the transmission channel established by the relay UE.

After the relay UE and the UPF network element have completed the configuration of the above mapping relationship, for uplink transmission, the remote UE sends a data packet to the relay UE, and the relay UE encapsulates the data packet with the first address, and passes it through the relay UE. The established transmission channel sends the data packet to the UPF network element. The UPF network element receives the data packet from the relay UE through the transmission channel established by the relay UE, and then sends the data packet to the network server. In this way, through the above mapping relationship configuration, there is no need for the remote UE and the network server. The transmission layer connection is re-established to realize the uninterrupted communication between the remote UE and the network server after the transmission path is switched, ensuring business continuity.

For downlink transmission, the UPF network element receives a data packet from the network server, the data packet includes the first address, the UPF network element sends the data packet to the relay UE through the transmission channel according to the mapping relationship, and the relay UE reuses the fourth address Encapsulate the data packet and send the encapsulated data packet to the remote UE. In this way, through the configuration of the mapping relationship described above, the remote UE and the network server do not need to re-establish the transport layer connection, so that the transmission path After the handover, the communication between the remote UE and the network server is not interrupted, ensuring business continuity.

The above method will be further described with an example in combination with the scenario shown in FIG. 3B below. Specifically, this example includes the following steps, as shown in FIG. 9A.

Steps 900 to 906 are the same as steps 501 to 506 shown in FIG. 5A in the first embodiment.

In step 907, the SMF network element determines the first address used by the non-direct communication link before the transmission path of the remote UE is switched (ie, IP1-1 in FIG. 9B), and determines the non-direct communication after the transmission path of the remote UE is switched. The transmission channel corresponding to the communication link (that is, the second non-direct communication link in FIG. 9B).

Specifically, the SMF network element may obtain the context information corresponding to the identifier of the remote UE from the UDM or from the local storage of the SMF network element, and determine the first address according to the context information. Or the SMF network element may determine the first address from the message received from the relay UE.

Step 908: The SMF network element sends a configuration message to the UPF network element, where the configuration message includes the mapping relationship between the first address and the transmission channel established by the relay UE.

Step 909: The SMF network element sends the first address to the second relay UE.

Step 910: The second relay UE determines the mapping relationship between the first address (ie IP1-1 in FIG. 9B) and the fourth address corresponding to the PC5 link (ie IP3 in FIG. 9B), and the second relay UE determines the mapping relationship according to The mapping relationship transmits the data of the remote UE.

Step 911, because the UPF network element is configured with the association relationship between the first address and the transmission channel established by the second relay UE, the UPF network element transmits the remote UE’s data according to the mapping relationship between the first address and the transmission channel. data.

With reference to Figure 9B, after the second relay UE and the UPF network element complete the above configuration, for uplink transmission data, the second relay UE converts the IP3 address in the data packet from the remote UE to an IP1-1 address, and then The transmission is performed through the PDU session established by the second relay UE. After the UPF network element receives the data packet through the session, it sends the second data packet to the network server. In this way, for the network server, the remote UE uses the same IP1 before and after the transmission path of the remote UE is switched. -1 to communicate with the server on the network side, so business continuity can be guaranteed. For downlink transmission data, the UPF network element forwards the data packet encapsulated in IP1-1 to the second relay UE through the PDU session of the second relay UE, and the second relay UE encapsulates the data packet with the IP3 address to obtain The encapsulated data packet is sent to the remote UE. In this way, for the remote UE, before and after the transmission path of the remote UE is switched, the remote UE uses the same IP3 address and the first The second relay UE communicates, so the continuity of the service can be guaranteed.

In the embodiment of the present application, after the transmission path of the remote UE is switched, there is no need to re-establish the transport layer connection between the remote UE and the network server. The SMF network element configures the UPF network element with the above-mentioned first address and relay UE. The mapping relationship between the established transmission channels and the mapping relationship between the first address and the fourth address configured by the relay UE, so that the UPF network element can realize the remote UE and the network server to use the transmission path according to the mapping relationship The address used before the handover is used for communication, that is, through the network side configuration, the communication between the remote UE and the network server is not interrupted after the transmission path is switched, and the business continuity is ensured.

Example four

Refer to Figure 10A, which is a schematic flow chart of the fourth method for realizing service continuity provided by an embodiment of this application. This method is suitable for the scenario shown in Figure 3C. The transmission path of the remote UE is transferred from the same SMF network before and after handover The element is responsible for management, and the UPF network elements on the transmission path before and after the switch are the same UPF network element. The method includes the following steps.

Step 1000: Before the remote UE switches the transmission path, the remote UE connects to the network through the first relay UE, the SMF network element allocates an address (for example, IP1 in FIG. 10B) to the first relay UE, and the first relay UE After establishing a transmission channel with the UPF network element, the first relay UE allocates a first address (for example, IP1-1 in FIG. 10B) to the remote UE. The SMF network element can record the association relationship between the identity of the first relay UE, the PDU session identifier, DNN, S-NSSAI, IP1, the identification information of the remote UE, and the first address. The association relationship can be used as the remote UE’s The subscription information is stored in UDR or UDM. The SMF network element may also obtain the mapping relationship from the UDR or UDM.

Step 1001: The remote UE sends a first message to the AMF network element. The first message includes the identifier of the remote UE, and the first message may be a PDU session establishment message. In a possible situation, the first message may also include a first indication, such as a transmission path switching indication (path switching indication), where the first indication is used to indicate a request to switch the transmission path of the remote UE.

It should be noted that before the remote UE sends the first message to the AMF network element, the connection with the first relay UE may have been disconnected; or, after the remote UE establishes a connection with the second relay UE, the remote UE Disconnect from the first relay UE, where the second relay UE refers to the relay UE accessed by the remote UE after the transmission path is switched.

Step 1002: The AMF network element forwards the identification information (or the first indication) of the remote UE in the message to the SMF network element.

Optionally, the method further includes step 1003. The SMF network element may determine whether the transmission path of the remote UE is switched according to the identification information of the remote UE, or the SMF network element may determine whether the transmission path of the remote UE is switched according to the first indication A switch occurs.

Optionally, the method further includes step 1004. After the SMF network element determines that the transmission path of the remote UE is switched, it further obtains the subscription information of the remote UE from the UDM. The subscription information indicates whether the remote UE has service continuity. If yes, the SMF network element continues to perform the subsequent steps, otherwise, it executes in accordance with the existing method.

Step 1005: The SMF network element configures a fifth address (for example, IP5 in FIG. 10B) for the newly created PDU session, and determines the first address used by the non-direct communication link before the transmission path of the remote UE is switched (that is, in FIG. 10B). IP1-1).

Regarding the first address, specifically, the SMF network element may adopt any one of the method 1 or the method 2 in step 403 in the foregoing implementation 1 to determine the first address. For details, please refer to the above step 403, which will not be repeated here.

Step 1006: The SMF network element sends a fifth address to the remote UE, where the fifth address is used to transmit data between the remote UE and the UPF network element.

Step 1007, because the PC5 communication link is established between the remote UE and the first relay before the transmission path is switched, the remote UE transmits data to the first relay UE through the sixth address (IP3 in FIG. 10B), Therefore, the remote UE establishes a mapping relationship between the fifth address (IP5 in FIG. 10B) and the sixth address ((IP3 in FIG. 10B)), and transmits the data of the remote UE according to the mapping relationship.

Specifically, when transmitting uplink data, the remote UE can convert the sixth address in the uplink data packet to a fifth address, and when transmitting downlink data, the remote UE can convert the fifth address in the downlink data packet to a fifth address. Six address.

Step 1008: The SMF network element sends a configuration message to the UPF network element, where the configuration message is used to configure the mapping relationship between the fifth address (IP5 in Figure 10B) and the first address (IP1-1 in Figure 10B) , The mapping relationship is used to transmit the data of the remote UE.

Step 1009: The UPF network element configures the mapping relationship between the fifth address (IP5 in FIG. 10B) and the first address (IP1-1 in FIG. 10B), and transmits data of the remote UE according to the mapping relationship.

With reference to Figure 10B, after the remote UE and the UPF network element have completed the above configuration, for the uplink transmission data, the network layer of the remote UE receives the IP3 encapsulated data packet, and then uses IP5 to re-encapsulate the data packet. The remote UE uses all the data packets. The established PDU session transmits the encapsulated data packet to the UPF network element, and the UPF network converts IP5 in the received data packet to IP1-1, and sends the converted data packet to the network server. For downlink transmission data, after the UPF network element receives a data packet containing IP1-1 from the network server side, it converts IP1-1 in the data packet to IP5, and uses the PDU session of the remote UE to transmit the converted data After receiving the converted data packet, the remote UE converts IP5 in the data packet to IP3.

In another possible embodiment, for the scenario shown in FIG. 3C to which the fourth implementation is applicable, the SMF network element may also allocate a seventh address visible to the network server side for the remote UE, and the seventh address is used for The data of the remote UE is transmitted between the UPF network element and the network server side. Exemplarily, with reference to FIG. 10B, the seventh address refers to the IP7 allocated by the SMF network element to the remote UE, and the IP7 is visible to the network server side. In this case, the above step 1008 can be replaced by: the SMF network element sends a configuration message to the UPF network element, the configuration message is used to configure the fifth address (IP5 in Figure 10C) and the seventh address (IP7 in Figure 10C) ) Mapping relationship, which is used to transmit data of the remote UE.

The above step 1009 can be replaced by: the UPF network element transmits the data of the remote UE according to the seventh address (IP5 in FIG. 10C) and the fifth address (IP7 in FIG. 10C).

With reference to Figure 10C, after the second relay UE and the UPF network element have completed the configuration of the above mapping relationship, for the uplink transmission data, the first relay UE detects the data packet containing IP3 from the remote UE, and then transfers the data The IP3 of the packet is converted to IP5, and the converted data packet is mapped to the PDU session of the first relay UE for transmission. The UPF network element detects that the received data packet contains IP5, and then converts the IP5 after the data packet to IP7, and send the converted data packet to the network server. For downlink transmission data, when the UPF network element detects a data packet containing IP7 from the network server, it converts the IP7 of the data packet to IP5 and maps it to the PDU session established by the UPF network element for transmission. Subsequently, the UE converts IP5 in the data packet received from the UPF network element to IP3, and sends the converted data packet to the remote UE.

In the embodiment of the present application, after the transmission path of the remote UE is switched, there is no need to re-establish the transport layer connection between the remote UE and the network server. The SMF network element configures the UPF network element with the above-mentioned first address and relay UE. The mapping relationship between the established transmission channels enables the remote UE and the network server to communicate using the address used before the transmission path switch, that is, through the network side configuration, the remote UE and the network server are realized after the transmission path switch Communication is not interrupted to ensure business continuity.

Example five

Refer to Figure 11A, which is a schematic flowchart of the fifth method for realizing service continuity provided by an embodiment of this application. This method is suitable for the scenarios shown in Figure 3A and Figure 3B. One SMF network element is responsible for management, and the UPF network elements on the transmission path before and after the handover are different UPF network elements. Assuming that the first transmission path before the handover includes a first UPF network element, and the second transmission path after the handover includes a second UPF network element, the method includes the following steps.

Step 1101, the remote UE is switched to the relay UE, and the remote UE is connected to the network through the relay UE. The remote UE can establish a PC5 communication link with the relay UE. The remote UE will use the fourth address for communication in the PC5 communication link. (IP3 in FIG. 11B) is notified to the second relay UE.

Step 1102: The SMF network element receives the first message from the relay UE.

Wherein, the first message may be a PDU session establishment message or a PDU session modification request message. Exemplarily, with reference to FIG. 3B, the remote UE switches from the first relay UE to the second relay UE, and the remote UE sends a relay access request message to the second relay UE, and the relay access The request message includes at least the remote UE's identification information (remote UE ID). The identification information of the remote UE may also be used to indicate that the transmission path of the remote UE is switched, so that the SMF network element can determine that the transmission path of the remote UE is switched.

It should be noted that the remote UE may have disconnected from the first relay UE before sending the first message to the AMF network element; or, when the second relay UE establishes a second transmission channel with the second UPF network element After that, the remote UE is disconnected from the first relay UE, where the second transmission channel may be a PDU session established by the second relay UE.

In a possible embodiment, the first message may further include a first indication, such as a transmission path switching indication (path switching indication), where the first indication is used to indicate a request to switch the transmission path of the remote UE. Exemplarily, with reference to FIG. 3B, the remote UE switches from the first relay UE to the second relay UE, the remote UE sends a relay access request message to the second relay UE, and the second relay UE After receiving the relay access request message, the second relay UE sends a PDU session establishment message or a PDU session modification request message to the SMF network element, and the message carries the identification information of the remote UE and the first indication , So that the SMF network element determines that the transmission path of the remote UE is switched according to the first indication.

Step 1103: The SMF network element determines the first address used by the communication link of the remote UE before the transmission path switching (IP1-1 in FIG. 11B).

The first address refers to the address used by the first UPF network element on the transmission path of the remote UE to transmit data of the remote UE before the transmission path is switched. The first address may refer to at least one of an IP address and a port number. Among them, the specific method for determining the first address can refer to the first method and the second method in step 403 in the first embodiment, which will not be repeated here.

Step 1104: The SMF network element sends the first address to the relay UE.

Optionally, the relay UE obtains the first address from the remote UE.

Step 1105: The relay UE receives the first address from the SMF network element, configures the mapping relationship between the first address and the fourth address (IP3 in Figure 11B), and uses the mapping relationship to transmit the remote UE's top and bottom. Row data.

Specifically, for uplink transmission, the remote UE sends uplink data to the relay UE, the relay UE receives a first data packet from the remote UE, the first data packet includes a fourth address, and the relay UE according to the first address The mapping relationship between the fourth address and the first address is used to encapsulate the first data packet to obtain the encapsulated second data packet, and then the second data packet is sent to the network side. For downlink transmission, after the relay UE receives the third data packet from the network side, the third data packet includes the first address, and the relay UE uses the fourth address pair according to the mapping relationship between the first address and the fourth address. The third data packet is encapsulated to obtain the encapsulated fourth data packet, and then the fourth data packet is sent to the remote UE.

In a possible embodiment, the method further includes step 1106. After receiving the first message, the SMF network element determines whether the remote UE has the authority to achieve service continuity, and if so, continues to perform the subsequent steps, otherwise , It is not executed.

Step 1107: The SMF network element determines that there are two UPFs associated with the remote UE, that is, the first UPF network element in the first transmission path before the remote UE is switched, and the second transmission path after the remote UE is switched. The second UPF network element. If two UPFs are associated, the SMF network element instructs the first UPF network element and the second UPF network element to establish a third transmission channel, which can be a forwarding tunnel between the first UPF network element and the second UPF network element , The SMF network element can also configure the actions of the first UPF network element and the second UPF network element.

Specifically, the SMF network element instructs the first UPF network element to establish and detect the data packet with the first address, and establish a forwarding tunnel. The first UPF network element returns the configured tunnel endpoint identifier (TEID of UPF1) to the SMF network element. The SMF network element instructs the second UPF network element to forward the data, forwards the data received from the TEID of UPF1 to the PDU session established by the relay UE, and establishes the forwarding tunnel; the first UPF network element returns the configured tunnel endpoint identifier ( TEID of UPF2); The SMF network element sends the TEID of UPF2 to the first UPF network element, and instructs the forwarding data to be sent to the TEID of UPF2.

Step 1108: The SMF network element instructs the first UPF network element to establish a mapping relationship between the first address and the third transmission channel, and the first UPF network element transmits data of the remote UE according to the mapping relationship.

With reference to FIG. 11B, the SMF network element instructs the first UPF network element to establish a mapping relationship between IP1-1 and the third transmission channel. Specifically, the SMF network element instructs the first UPF network element to detect the IP1-1 data packet and establish a forwarding tunnel. The first UPF network element returns the configured tunnel endpoint identifier (TEID of UPF1), where TEID (Tunnel Endpoint ID) is the tunnel end endpoint identifier.

Step 1109: The SMF network element instructs the second UPF network element to establish a mapping relationship between the first address, the second transmission channel, and the third transmission channel.

Specifically, the SMF network element instructs the second UPF network element to forward data, forward the data received from the TEID of UPF1 to the PDU session of the second relay UE, and establish a forwarding tunnel. The second UPF network element returns the configured tunnel endpoint identifier (TEID of UPF2). In addition, in a possible implementation, the SMF network element may also send the TEID of UPF2 to the first UPF network element, instructing the forwarding data to be sent to the TEID of UPF2.

Step 1110: The second UPF network element and the first UPF network element transmit data of the remote UE according to the mapping relationship between the first address, the second transmission channel, and the third transmission channel.

With reference to Figure 11B, for downlink data transmission, after the first UPF network element detects IP1-1 data, it is sent to the second UPF network element through the third transmission channel, and the second UPF network element will receive it from the third transmission channel The data of is sent to the second transmission channel, and the second relay UE converts the IP 1-1 in the received data packet to IP3, and sends the converted data to the remote UE. For uplink data transmission, after the second relay UE detects a data packet containing IP3, it converts the IP3 after the data packet to IP1-1, and uses the PDU session established by the second relay UE to transmit to the second UPF network element , The second UPF network element sends the IP1-1 encapsulated data packet received from the second transmission channel to the third transmission channel, and the first UPF network element receives the data packet from the second UPF network element through the third transmission channel. After the IP1-1 data packet, it is sent to the network server.

In the embodiment of this application, after the transmission path of the remote UE is switched, there is no need to re-establish the transport layer connection between the remote UE and the network server. The SMF network element configures the above-mentioned configuration to the first UPF network element and the second UPF network element. The mapping relationship and the configuration of the above-mentioned mapping relationship by the relay UE enable the UPF network element to implement the communication between the remote UE and the network server using the address used before the transmission path switch based on the mapping relationship. After the path is switched, the communication between the remote UE and the network server is not interrupted, ensuring business continuity.

Example Six

Refer to Figure 12A, which is a schematic flow chart of the sixth method for realizing service continuity provided by an embodiment of this application. This method is suitable for the scenarios shown in Figures 3A and 3B. One SMF network element is responsible for management, and the UPF network elements on the transmission path before and after the handover are different UPF network elements. Assuming that the first transmission path before the handover includes a first UPF network element, and the second transmission path after the handover includes a second UPF network element, the method includes the following steps.

Step 1201: The remote UE switches to the relay UE, and connects to the network through the relay UE. The remote UE can establish a PC5 communication link with the relay UE. The remote UE will use the fourth address for communication in the PC5 communication link. (IP3 in FIG. 11B) is notified to the second relay UE. After the relay UE establishes a PDU session with the second UPF network element, it configures a second address for the remote UE (as shown in Figure 12B to IP2-1).

Step 1202 to step 1207 are the same as the above step 1102 to step 1107.

Step 1208: The SMF network element instructs the first UPF network element to establish a mapping relationship between the first address, the second address, and the third transmission channel, so that the first UPF network element transmits data of the remote UE according to the mapping relationship.

With reference to FIG. 12B, the SMF network element instructs the first UPF network element to establish a mapping relationship between IP1-1, IP2-1, and the third transmission channel. Specifically, the SMF network element instructs the first UPF network element to detect the IP1-1 data packet and establish a forwarding tunnel. The first UPF network element returns the configured tunnel endpoint identifier (TEID of UPF1), where TEID (Tunnel Endpoint ID) is the tunnel end endpoint identifier.

Step 1209: The SMF network element instructs the second UPF network element to establish a mapping relationship between the second address, the second transmission channel, and the third transmission channel.

Step 1210: The second UPF network element and the first UPF network element transmit data of the remote UE according to the mapping relationship between the second address, the second transmission channel, and the third transmission channel.

With reference to Figure 12B, for downlink data transmission, the first UPF network element receives a data packet from the network server side, and when it detects data containing IP1-1, it converts the IP1-1 after the data packet to IP2-1, and Send to the second UPF network element through the third transmission channel, the second UPF network element sends the data received from the third transmission channel to the second transmission channel, and the second relay UE converts the IP2-1 in the data packet to After IP3, it is sent to the remote UE. For uplink data transmission, the second relay UE detects a data packet containing IP 3, converts the IP3 after the data packet to IP2-1, and uses the PDU session established by the second relay UE for transmission. The UE sends the IP 2-1 data received from the second transmission channel to the third transmission channel. After the first UPF network element receives the data from the third transmission channel, it converts the IP2-1 in the data packet to IP1- 1. Send the converted data packet to the network server side.

In the embodiment of the present application, before and after the transmission path of the remote UE is switched, for the network server, the address of the remote UE on the opposite side has not changed, and for the remote UE, the address of the network server on the opposite side has not changed. Therefore, business continuity can be guaranteed.

In another possible embodiment, the above step 1208 may be replaced with: the SMF network element instructs the first UPF network element to establish the mapping relationship between the first address and the third transmission channel.

With reference to Figure 12C, for downlink data transmission, the first UPF network element receives a data packet from the network server side, and when it detects a data packet containing IP1-1, it sends the data packet to the second UPF through the third transmission channel. Network element, the second UPF network element re-encapsulates the data packet received from the third transmission channel with IP2-1 and sends it to the second transmission channel. After the second relay UE converts the IP2-1 in the data packet to IP3 Sent to the remote UE. For uplink data transmission, the second relay UE detects a data packet containing IP 3, converts the IP3 after the data packet to IP2-1, and uses the PDU session established by the second relay UE for transmission. The UE re-encapsulates the IP 2-1 data packet received from the second transmission channel with IP1-1, and then sends the third transmission channel. After the first UPF network element receives the data packet from the third transmission channel, the data The packet is sent to the web server side.

Example Seven

Refer to FIG. 13A, which is a schematic flow chart of the seventh method for realizing service continuity provided by an embodiment of this application. This method is suitable for the scenarios shown in FIGS. 3A and 3B. The network elements are responsible for management, and the UPF network elements on the transmission path before and after the switch are different UPF network elements. Assuming that the first transmission path before the handover includes the first UPF network element, the second transmission path after the handover includes the second UPF network element, and the first SMF is responsible for session management on the transmission path before the handover. The second SMF is responsible for the session management of the transmission path, and the method includes the following steps.

Step 1301: The remote UE switches to the relay UE, and connects to the network through the relay UE. The remote UE can establish a PC5 communication link with the relay UE. The remote UE will use the fourth address for communication in the PC5 communication link. (IP3 in Fig. 13B) is notified to the second relay UE.

It should be noted that before the remote UE switches the transmission path, after the first SMF network element configures the first address (for example, IP1-1 in FIG. 5B) for the remote UE, the first SMF network element records "IP1- 1 is in use", and can store the context of the PDU session before the transmission path, that is, the first address has not been released, and the SMF network element cannot allocate the first address to other remote UEs. .

Step 1302: After the transmission path of the remote UE is switched, the second SMF network element receives the first message from the relay UE.

Wherein, the first message may be a PDU session establishment message or a PDU session modification request message. Exemplarily, with reference to FIG. 3B, the remote UE switches from the first relay UE to the second relay UE, and the remote UE sends a relay access request message to the second relay UE, and the relay access The request message includes at least the remote UE's identification information (remote UE ID). The identification information of the remote UE may also be used to indicate that the transmission path of the remote UE is switched, so that the second SMF network element can determine that the transmission path of the remote UE is switched.

In a possible embodiment, the method further includes step 1303. After receiving the first message, the SMF network element determines whether the remote UE has the authority to achieve service continuity, and if so, continues to perform the subsequent steps, otherwise , It is not executed.

For the specific method for determining whether the remote UE has the authority to achieve service continuity, refer to step 404 in the above-mentioned embodiment 1, which will not be repeated here. Step 1304a: The second SMF network element sends a request message to the UDM according to the identifier of the remote UE in the first message. The request message is used to request the remote UE to use the address of the communication link before the transmission path is switched (as shown in Figure 13B IP1-1) and SMF network element information. Step 1304b: The second SMF network element receives a notification message from UDM, where the notification message includes the first address and the first SMF network element information.

It should be noted that before the transmission path of the remote UE is switched, the first SMF is responsible for the session management of the transmission path before the switch. The first SMF network element associates the identification information of the remote UE with the first SMF network element. The relationship is reported to UDM and stored by UDM.

Optionally, if the step 1302 message includes the address used by the communication link of the remote UE before the transmission path switching, the request message is used to request the SMF network element responsible for managing the communication link of the remote UE before the transmission path switching information. Correspondingly, the first address is not included in the step 1304b message.

The first address refers to the address used by the first UPF network element to transmit data of the remote UE before the remote UE is switched. The first address may refer to at least one of an IP address and a port number. For the specific method for determining the first address, reference may be made to step 403 in the first embodiment above, which will not be repeated here.

Step 1305: The second SMF network element sends the first address to the relay UE.

Step 1306: The relay UE receives the first address from the second SMF network element, configures the mapping relationship between the first address and the fourth address (IP3 in Figure 13B), and uses the mapping relationship to transmit the remote UE Upstream and downstream data.

Step 1307: The first SMF and the second SMF network element respectively instruct the first UPF and the second UPF network element to establish a third transmission channel, and the third transmission channel is a forwarding between the first UPF network element and the second UPF network element tunnel.

Optionally, the second SMF network element determines that there are two UPFs associated with the remote UE, that is, the first UPF in the first transmission path before the remote UE is handed over, and the second transmission path after the remote UE is handed over The second UPF. Then it requests the first SMF to establish the third transmission channel. .

Specifically, the first SMF network element instructs the first UPF network element to establish and detect the data packet with the first address, and establish a forwarding tunnel. The first UPF network element returns the configured tunnel endpoint identifier (TEID of UPF1) to the SMF network element. The second SMF network element instructs the second UPF network element to forward the data, forwards the data received from the TEID of UPF1 to the PDU session established by the relay UE, and establishes the forwarding tunnel; the first UPF network element returns the configured tunnel endpoint Identification (TEID of UPF2); the first SMF network element sends TEID of UPF2 to the first UPF network element, indicating that the forwarded data is sent to TEID of UPF2.

Step 1308: The first SMF network element instructs the first UPF network element to establish a mapping relationship between the first address and the third transmission channel, and the first UPF network element transmits data of the remote UE according to the mapping relationship.

With reference to FIG. 13B, the first SMF network element instructs the first UPF network element to establish a mapping relationship between IP1-1 and the third transmission channel. Specifically, the SMF network element instructs the first UPF network element to detect the IP1-1 data packet and establish a forwarding tunnel. The first UPF network element returns the configured tunnel endpoint identifier (TEID of UPF1), where TEID (Tunnel Endpoint ID) is the tunnel end endpoint identifier.

Step 1309: The second SMF network element instructs the second UPF network element to establish a mapping relationship between the first address, the second transmission channel, and the third transmission channel.

With reference to FIG. 13B, the second SMF network element instructs the second UPF network element to establish a mapping relationship between IP1-1, the second transmission channel, and the third transmission channel.

The second transmission channel is a transmission tunnel that relays the PDU session established by the UE.

Step 1310: The second UPF network element and the first UPF network element transmit data of the remote UE according to the mapping relationship between the first address, the second transmission channel, and the third transmission channel.

With reference to Figure 13B, for downlink data transmission, after the first UPF network element detects IP1-1 data, it is sent to the second UPF network element through the third transmission channel, and the second UPF network element will receive it from the third transmission channel The data of is sent to the second transmission channel, and the second relay UE converts the IP 1-1 in the received data packet to IP3, and sends the converted data to the remote UE. For uplink data transmission, after the second relay UE detects a data packet containing IP3, it converts the IP3 after the data packet to IP1-1, and uses the PDU session established by the second relay UE to transmit to the second UPF network element , The second UPF network element sends the data packet received from the second transmission channel to the third transmission channel. After the first UPF network element receives the IP1-1 data packet from the second UPF network element through the third transmission channel , And then sent to the web server.

In another possible embodiment, in the foregoing step 1309: the SMF network element further instructs the second UPF network element to establish a mapping relationship between the first address and the second address. Correspondingly, in step 1306: the relay UE configures the mapping relationship between the second address and the fourth address.

The specific forwarding process is similar to that described in Figure 12C. For downlink data transmission, the first UPF network element receives a data packet from the network server side, and when it detects a data packet containing IP1-1, it sends the data packet to the second UPF network element through the third transmission channel, and the second UPF The network element re-encapsulates the data packet received from the third transmission channel with IP2-1 and sends it to the second transmission channel. The second relay UE converts the IP2-1 in the data packet to IP3 and sends it to the remote UE. For uplink data transmission, the second relay UE detects a data packet containing IP 3, converts the IP3 after the data packet to IP2-1, and uses the PDU session established by the second relay UE for transmission. The UE re-encapsulates the IP 2-1 data packet received from the second transmission channel with IP1-1, and then sends the third transmission channel. After the first UPF network element receives the data packet from the third transmission channel, the data The packet is sent to the web server side.

It should be noted that when the context of the remote UE is not released, the first SMF network element marks the first address as a use state. When the second SMF network element determines that the PDU session established by the second relay UE is released, or the second relay UE requests to release the context of the remote UE (corresponding to the release of the PC5 connection between the second relay UE and the remote UE) ), the second SMF network element notifies the first SMF network element to release the context of the remote UE. After receiving the notification, the first SMF network element marks the first address as a released state. That is, the first address is released, and the SMF network element can allocate the first address to other remote UEs.

Regarding the foregoing Embodiments 1 to 7, it should be noted that: (1) The foregoing Embodiments 1 and 7 can be implemented separately in different scenarios, or they can be implemented in combination in the same scenario, or different implementations. The different solutions involved in the examples can also be implemented in combination (for example, part or all of the solutions involved in the first embodiment can be implemented in combination with the third embodiment), which is not specifically limited.

(2) The step numbers of the flowcharts described in the embodiments of the present application are only an example of the execution process, and do not constitute a restriction on the order of execution of the steps. There is no timing dependency between the embodiments of the present application. There is no strict order of execution between the steps.

The foregoing mainly introduces the solution provided by the embodiment of the present application from the perspective of interaction between the network device and the terminal device. It can be understood that, in order to implement the above-mentioned functions, the network device or the terminal device may include a hardware structure and/or software module corresponding to each function. Those skilled in the art should easily realize that in combination with the units and algorithm steps of the examples described in the embodiments disclosed herein, the embodiments of the present application can be implemented in the form of hardware or a combination of hardware and computer software. Whether a certain function is executed by hardware or computer software-driven hardware depends on the specific application and design constraint conditions of the technical solution. Professionals and technicians can use different methods for each specific application to implement the described functions, but such implementation should not be considered beyond the scope of this application.

The embodiment of the present application may divide the terminal device and the network device into functional units according to the foregoing method examples. For example, each functional unit may be divided corresponding to each function, or two or more functions may be integrated into one unit. The above-mentioned integrated unit can be implemented in the form of hardware or software functional unit.

In the case of using an integrated unit, FIG. 14 shows a possible exemplary block diagram of a device involved in an embodiment of the present application. As shown in FIG. 14, the apparatus 1400 may include: a processing unit 1402 and a communication unit 1403. The processing unit 1402 is used to control and manage the actions of the device 1400. The communication unit 1403 is used to support communication between the apparatus 1400 and other devices. Optionally, the communication unit 1403 is also called a transceiving unit, and may include a receiving unit and/or a sending unit, which are used to perform receiving and sending operations, respectively. The device 1400 may further include a storage unit 1401 for storing program codes and/or data of the device 1400.

The apparatus 1400 may be the terminal device in any of the foregoing embodiments, or may also be a chip provided in the terminal device. The processing unit 1402 may support the apparatus 1400 to execute the actions of the terminal device in the above method examples. Alternatively, the processing unit 1402 mainly executes the internal actions of the terminal device in the method example, and the communication unit 1403 can support communication between the apparatus 1400 and the network device.

The apparatus 1400 may be the network device in any of the foregoing embodiments, or may also be a chip in the network device. The processing unit 1402 may support the apparatus 1400 to execute the actions of the network device in the above method examples. Alternatively, the processing unit 1402 mainly executes the internal actions of the network device in the method example, and the communication unit 1403 can support communication between the apparatus 1400 and the network device.

It should be understood that the division of units in the above device is only a division of logical functions, and may be fully or partially integrated into one physical entity in actual implementation, or may be physically separated. In addition, the units in the device can be all implemented in the form of software called by processing elements; they can also be all implemented in the form of hardware; part of the units can also be implemented in the form of software called by the processing elements, and some of the units can be implemented in the form of hardware. For example, each unit can be a separate processing element, or it can be integrated in a certain chip of the device for implementation. In addition, it can also be stored in the memory in the form of a program, which is called and executed by a certain processing element of the device. Function. In addition, all or part of these units can be integrated together or implemented independently. The processing element described here can also become a processor, which can be an integrated circuit with signal processing capabilities. In the implementation process, each step of the above method or each of the above units may be implemented by an integrated logic circuit of hardware in a processor element or implemented in a form of being called by software through a processing element.

In an example, the unit in any of the above devices may be one or more integrated circuits configured to implement the above methods, for example: one or more application specific integrated circuits (ASICs), or, one or Multiple microprocessors (digital singnal processors, DSPs), or, one or more field programmable gate arrays (Field Programmable Gate Arrays, FPGAs), or a combination of at least two of these integrated circuits. For another example, when the unit in the device can be implemented in the form of a processing element scheduler, the processing element can be a processor, such as a general-purpose central processing unit (central processing unit, CPU), or other processors that can call programs. For another example, these units can be integrated together and implemented in the form of a system-on-a-chip (SOC).

The above receiving unit is an interface circuit of the device for receiving signals from other devices. For example, when the device is implemented as a chip, the receiving unit is an interface circuit used by the chip to receive signals from other chips or devices. The above unit for sending is an interface circuit of the device for sending signals to other devices. For example, when the device is implemented in the form of a chip, the sending unit is an interface circuit used by the chip to send signals to other chips or devices.

Please refer to FIG. 15, which is a schematic structural diagram of a terminal device according to an embodiment of the application. It may be the terminal device in the above embodiment, and is used to implement the operation of the terminal device in the above embodiment. As shown in FIG. 15, the terminal device includes: an antenna 1510, a radio frequency part 1520, and a signal processing part 1530. The antenna 1510 is connected to the radio frequency part 1520. In the downlink direction, the radio frequency part 1520 receives the information sent by the network device through the antenna 1510, and sends the information sent by the network device to the signal processing part 1530 for processing. In the upstream direction, the signal processing part 1530 processes the information of the terminal equipment and sends it to the radio frequency part 1520, and the radio frequency part 1520 processes the information of the terminal equipment and sends it to the network equipment via the antenna 1510.

The signal processing part 1530 may include a modem subsystem, which is used to process data at various communication protocol layers; it may also include a central processing subsystem, which is used to process terminal equipment operating systems and application layers.

The modem subsystem may include one or more processing elements 1531, for example, including a main control CPU and other integrated circuits. In addition, the modem subsystem may also include a storage element 1532 and an interface circuit 1533. The storage element 1532 is used to store data and programs, but the program used to execute the method performed by the terminal device in the above method may not be stored in the storage element 1532, but stored in a memory outside the modem subsystem, When in use, the modem subsystem is loaded and used. The interface circuit 1533 is used to communicate with other subsystems.

The modem subsystem can be implemented by a chip, the chip includes at least one processing element and an interface circuit, wherein the processing element is used to execute each step of any method executed by the above terminal device, and the interface circuit is used to communicate with other devices. In one implementation, the unit for the terminal device to implement each step in the above method can be implemented in the form of a processing element scheduler. For example, the device for the terminal device includes a processing element and a storage element, and the processing element calls the program stored by the storage element to Perform the method performed by the terminal device in the above method embodiment. The storage element may be a storage element whose processing element is on the same chip, that is, an on-chip storage element.

In another implementation, the program used to execute the method executed by the terminal device in the above method may be a storage element on a different chip from the processing element, that is, an off-chip storage element. At this time, the processing element calls or loads a program from the off-chip storage element on the on-chip storage element to call and execute the method executed by the terminal device in the above method embodiment.

In yet another implementation, the unit of the terminal device that implements each step in the above method may be configured as one or more processing elements, and these processing elements are arranged on the modem subsystem, where the processing elements may be integrated circuits, For example: one or more ASICs, or, one or more DSPs, or, one or more FPGAs, or a combination of these types of integrated circuits. These integrated circuits can be integrated together to form a chip.

The units of the terminal device that implement each step in the above method can be integrated together and implemented in the form of an SOC, and the SOC chip is used to implement the above method. The chip can integrate at least one processing element and a storage element, and the processing element can call the stored program of the storage element to implement the method executed by the above terminal device; or, the chip can integrate at least one integrated circuit to implement the above terminal The method executed by the device; or, it can be combined with the above implementations. The functions of some units are implemented in the form of calling programs by processing elements, and the functions of some units are implemented in the form of integrated circuits.

It can be seen that the above apparatus for terminal equipment may include at least one processing element and an interface circuit, wherein at least one processing element is used to execute any of the methods performed by the terminal equipment provided in the above method embodiments. The processing element can execute part or all of the steps executed by the terminal device in the first way: calling the program stored in the storage element; or in the second way: combining instructions through the integrated logic circuit of the hardware in the processor element Part or all of the steps performed by the terminal device are executed in a manner; of course, part or all of the steps executed by the terminal device can also be executed in combination with the first manner and the second manner.

The processing element here is the same as that described above, and can be implemented by a processor, and the function of the processing element can be the same as the function of the processing unit described in FIG. 14. Exemplarily, the processing element may be a general-purpose processor, such as a CPU, or one or more integrated circuits configured to implement the above method, such as: one or more ASICs, or, one or more microprocessors DSP , Or, one or more FPGAs, etc., or a combination of at least two of these integrated circuit forms. The storage element may be realized by a memory, and the function of the storage element may be the same as the function of the storage unit described in FIG. 14. The storage element may be realized by a memory, and the function of the storage element may be the same as the function of the storage unit described in FIG. 14. The storage element can be a single memory or a collective term for multiple memories.

The terminal device shown in FIG. 15 can implement each of the terminal devices involved in the method embodiments illustrated in FIG. 4, FIG. 5A, FIG. 6, FIG. 7A, FIG. 8, FIG. 9A, FIG. 10A, FIG. 11A, FIG. 12A, or FIG. process. The operations and/or functions of the various modules in the terminal device shown in FIG. 15 are used to implement the corresponding processes in the foregoing method embodiments. For details, please refer to the descriptions in the above method embodiments. To avoid repetition, detailed descriptions are appropriately omitted here.

Please refer to FIG. 16, which is a schematic structural diagram of a network device provided by an embodiment of this application. It is used to implement the operation of the network device in the above embodiment. As shown in FIG. 16, the network equipment includes: an antenna 1601, a radio frequency device 1602, and a baseband device 1603. The antenna 1601 is connected to the radio frequency device 1602. In the uplink direction, the radio frequency device 1602 receives the information sent by the terminal device through the antenna 1601, and sends the information sent by the terminal device to the baseband device 1603 for processing. In the downlink direction, the baseband device 1603 processes the information of the terminal device and sends it to the radio frequency device 1602, and the radio frequency device 1602 processes the information of the terminal device and sends it to the terminal device via the antenna 1601.

The baseband device 1603 may include one or more processing elements 16031, for example, a main control CPU and other integrated circuits. In addition, the baseband device 1603 may also include a storage element 16032 and an interface 16033. The storage element 16032 is used to store programs and data; the interface 16033 is used to exchange information with the radio frequency device 1602. The interface is, for example, a common public radio interface. , CPRI). The above device for network equipment may be located in the baseband device 1603. For example, the above device for network equipment may be a chip on the baseband device 1603. The chip includes at least one processing element and an interface circuit, wherein the processing element is used to execute the above network. For each step of any method executed by the device, the interface circuit is used to communicate with other devices. In one implementation, the unit for the network device to implement each step in the above method can be implemented in the form of a processing element scheduler. For example, the device for the network device includes a processing element and a storage element, and the processing element calls the program stored by the storage element to Perform the method performed by the network device in the above method embodiment. The storage element may be a storage element with the processing element on the same chip, that is, an on-chip storage element, or a storage element on a different chip from the processing element, that is, an off-chip storage element.

In another implementation, the unit of the network device that implements each step in the above method may be configured as one or more processing elements, and these processing elements are arranged on the baseband device. The processing elements here may be integrated circuits, such as one Or multiple ASICs, or, one or more DSPs, or, one or more FPGAs, or a combination of these types of integrated circuits. These integrated circuits can be integrated together to form a chip.

The units for the network equipment to implement each step in the above method can be integrated together and implemented in the form of a system-on-a-chip (SOC). For example, the baseband device includes the SOC chip for implementing the above method. At least one processing element and storage element can be integrated in the chip, and the processing element can call the stored program of the storage element to implement the method executed by the above network device; or, at least one integrated circuit can be integrated in the chip to implement the above network The method executed by the device; or, it can be combined with the above implementations. The functions of some units are implemented in the form of calling programs by processing elements, and the functions of some units are implemented in the form of integrated circuits.

It can be seen that the above apparatus for a network device may include at least one processing element and an interface circuit, wherein at least one processing element is used to execute any of the methods performed by the network device provided in the above method embodiments. The processing element can execute part or all of the steps executed by the network device in the first way: calling the program stored in the storage element; or in the second way: combining instructions through the integrated logic circuit of the hardware in the processor element Part or all of the steps performed by the network device are executed in the method; of course, part or all of the steps executed by the network device above can also be executed in combination with the first method and the second method.

The network device shown in FIG. 16 can implement various processes related to the network device in the foregoing method embodiments. The operations and/or functions of the various modules in the network device shown in FIG. 16 are used to implement the corresponding processes in the foregoing method embodiments. For details, please refer to the descriptions in the above method embodiments. To avoid repetition, detailed descriptions are appropriately omitted here.

Those skilled in the art should understand that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, this application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, this application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

This application is described with reference to flowcharts and/or block diagrams of methods, equipment (systems), and computer program products according to this application. It should be understood that each process and/or block in the flowchart and/or block diagram, and the combination of processes and/or blocks in the flowchart and/or block diagram can be realized by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing equipment to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing equipment are generated It is a device that realizes the functions specified in one process or multiple processes in the flowchart and/or one block or multiple blocks in the block diagram.

These computer program instructions can also be stored in a computer-readable memory that can guide a computer or other programmable data processing equipment to work in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture including the instruction device. The device implements the functions specified in one process or multiple processes in the flowchart and/or one block or multiple blocks in the block diagram.

These computer program instructions can also be loaded on a computer or other programmable data processing equipment, so that a series of operation steps are executed on the computer or other programmable equipment to produce computer-implemented processing, so as to execute on the computer or other programmable equipment. The instructions provide steps for implementing the functions specified in one process or multiple processes in the flowchart and/or one block or multiple blocks in the block diagram.

Obviously, those skilled in the art can make various changes and modifications to the application without departing from the spirit and scope of the application. In this way, if these modifications and variations of this application fall within the scope of the claims of this application and their equivalent technologies, then this application is also intended to include these modifications and variations.

Claims

A method for realizing business continuity, which is characterized in that it includes:

The session management function network element receives a first message from a relay user equipment UE, the first message includes identification information of a remote UE connected to the relay UE, and the relay UE is the remote UE's UE to which the remote UE is connected after the transmission path is switched;

The session management function network element configures the mapping relationship between the first address and the second address to the user plane function network element, wherein the first address is used for the user plane function before the transmission path of the remote UE is switched The network element transmits the data of the remote UE, and the second address is used for the user plane function network element to transmit the data of the remote UE after the transmission path of the remote UE is switched.
The method according to claim 1, wherein the first message is used to establish a protocol data unit PDU session of the relay UE or modify a PDU session of the relay UE.
The method according to claim 1 or 2, wherein the identification information of the remote UE is used to indicate that the transmission path of the remote UE is switched.
The method according to claim 1 or 2, wherein the first message further comprises: a first indication, and the first indication is used to indicate a request to switch the transmission path of the remote UE.
The method according to any one of claims 1 to 4, wherein the method further comprises:

The session management function network element determines the first address according to the identification information of the remote UE.
The method according to any one of claims 1 to 4, wherein the method further comprises:

The session management function network element receives the first address from the remote UE.
The method according to any one of claims 1 to 6, wherein the method further comprises:

The session management function network element receives the second address from the relay UE.
The method according to claim 7, wherein before the session management function network element receives the second address from the relay UE, the method further comprises:

The session management function network element allocates a third address to the relay UE, and the third address is used to generate the second address.
The method according to claim 7 or 8, wherein:

The session management function network element sends the first address to the relay UE for configuring the mapping relationship between the first address and the second address.
The method according to any one of claims 1 to 9, wherein the method further comprises:

The session management function network element determines that the remote UE has the authority to achieve service continuity.
The method according to any one of claims 1 to 10, wherein the method further comprises:

After the transmission path of the remote UE is switched and the context information of the remote UE is deleted, the session management function network element releases the first address.
A method for realizing business continuity, which is characterized in that it includes:

The user plane function network element receives the mapping relationship between the first address and the second address from the session management function network element, where the first address is used for the user plane function network before the transmission path of the remote user equipment UE is switched. Element to transmit the data of the remote UE, and the second address is used to transmit the data of the remote UE by the user plane function network element after the transmission path of the remote UE is switched;

The user plane function network element transmits the data of the remote UE according to the mapping relationship.
The method according to claim 12, wherein the second address is used for the user plane function network element to transmit the data of the remote UE after the transmission path of the remote UE is switched, comprising:

The second address is used to transmit data of the remote UE between the user plane function network element and a second relay UE after the transmission path of the remote UE is switched, and the second relay UE is The relay UE to which the remote UE is connected after the transmission path of the remote UE is switched.
The method according to claim 13, wherein the first address is used for the user plane function network element to transmit the data of the remote UE before the transmission path of the remote UE is switched, comprising:

The first address is used to transmit data of the remote UE between the user plane function network element and the first relay UE before the transmission path of the remote UE is switched, and the first relay UE is The relay UE that the remote UE is connected to before the remote UE transmission path is switched; or,

The first address is used to transmit the data of the remote UE between the user plane function network element and the remote UE before the transmission path of the remote UE is switched.
The method according to claim 12, wherein the second address is used for the user plane function network element to transmit the data of the remote UE after the transmission path of the remote UE is switched, comprising:

The second address is used to transmit the data of the remote UE between the user plane function network element and the remote UE after the transmission path of the remote UE is switched.
The method according to claim 15, wherein the first address is used for the user plane function network element to transmit the data of the remote UE before the transmission path of the remote UE is switched, comprising:

The first address is used to transmit the data of the remote UE between the user plane function network element and the first relay UE before the transmission path of the remote UE is switched, and the first relay UE is The relay UE connected to the remote UE before the remote UE transmission path is switched.
A method for realizing business continuity, which is characterized in that it includes:

The session management function network element receives a first message from a relay user equipment UE, the first message includes identification information of a remote UE connected to the relay UE, and the relay UE is the remote UE's UE to which the remote UE is connected after the transmission path is switched;

Sending, by the session management function network element, a first address to the relay UE, where the first address is used for the user plane function network element to transmit the data of the remote UE before the transmission path switching of the remote UE; And used for the user plane function network element to transmit the data of the remote UE after the transmission path of the remote UE is switched;

The session management function network element configures the mapping relationship between the first address and the transmission channel to the user plane function network element, and the transmission channel is the transmission between the relay UE and the user plane function network element aisle.
The method according to claim 17, wherein the first message is used to establish a protocol data unit PDU session of the relay UE or modify the PDU session of the relay UE.
The method according to claim 17 or 18, wherein the identification information of the remote UE is used to indicate that the transmission path of the remote UE is switched.
The method according to claim 17 or 18, wherein the first message further comprises: a first indication, and the first indication is used to indicate a request to switch the transmission path of the remote UE.
The method according to any one of claims 17 to 20, wherein the method further comprises:

The session management function network element determines the first address according to the identification information of the remote UE.
The method according to any one of claims 17 to 21, wherein the method further comprises:

The session management function network element receives the first address from the remote UE.
The method according to claim 21 or 22, wherein the method further comprises:

The session management function network element sends the first address to the relay UE, which is used to configure the mapping relationship between the first address and the fourth address, and the fourth address is used for the relay UE and the relay UE. The data is transmitted between the remote UEs.
The method according to any one of claims 17 to 23, wherein the method further comprises:

The session management function network element determines that the remote UE has the authority to achieve service continuity.
The method according to any one of claims 17 to 24, wherein the method further comprises:

After the transmission path of the remote UE is switched and the context information of the remote UE is deleted, the session management function network element releases the first address.
A method for realizing business continuity, which is characterized in that it includes:

The user plane function network element receives the mapping relationship between the first address and the transmission channel from the session management function network element, where the first address is used for the user plane function network before the transmission path of the remote user equipment UE is switched. The data of the remote UE is transmitted by the remote UE, and the user plane function network element is used to transmit the data of the remote UE after the transmission path of the remote UE is switched. The transmission channel is the relay UE and the Transmission channel between user plane function network elements;

The user plane function network element transmits the data of the remote UE according to the mapping relationship.
The method according to claim 26, wherein the first address is used for the user plane function network element to transmit the data of the remote UE before the transmission path of the remote UE is switched, comprising:

The first address is used to transmit data of the remote UE between the user plane function network element and the first relay UE before the transmission path of the remote UE is switched, and the first relay UE is The relay UE that the remote UE is connected to before the remote UE transmission path is switched; or,

The first address is used to transmit data between the user plane function network element and the remote UE before the transmission path of the remote UE is switched.
A method for realizing business continuity, which is characterized in that it includes:

The relay user equipment UE receives the first address from the session management function network element. The first address is used to transmit the data of the remote UE by the user plane function network element before the transmission path of the remote UE is switched. After the transmission path of the remote UE is switched, the user plane function network element transmits the data of the remote UE, and the relay UE is the UE connected to the remote UE after the transmission path of the remote UE is switched ；

The relay UE transmits data of the remote UE according to the mapping relationship between the first address and the fourth address, and the fourth address is used to transmit data between the relay UE and the remote UE .
The method according to claim 28, wherein before the relay UE receives the first address from the session management function network element, the method comprises:

Receiving, by the relay UE, the identification information of the remote UE from the remote UE;

The relay UE sends a first message to the session management function network element, where the first message includes identification information of the remote UE, and the identification information of the remote UE is used to determine the first address.
The method according to claim 28 or 29, wherein the first message is used to establish a protocol data unit PDU session of the relay UE or modify the PDU session of the relay UE.
The method according to any one of claims 28 to 30, wherein the identification information of the remote UE is used to indicate that the transmission path of the remote UE is switched.
The method according to any one of claims 28 to 31, wherein the first message further comprises: a first indication, and the first indication is used to indicate a request to switch the transmission path of the remote UE.
A method for realizing business continuity, which is characterized in that it includes:

The session management function network element receives the identification information of the remote UE from the remote user equipment UE and the first indication, where the first indication is used to indicate that the transmission path of the remote UE is requested to be switched;

Sending, by the session management function network element, a fifth address to the remote UE, where the fifth address is used for data transmission between the remote UE and the user plane function network element;

The session management function network element configures the mapping relationship between the fifth address and the first address to the user plane function network element, and the first address is used to perform the mapping before the transmission path of the remote UE is switched. The user plane function network element transmits the data of the remote UE.
The method of claim 33, comprising:

The session management function network element receives the first address from the remote UE.
A method for realizing business continuity, which is characterized in that it includes:

The remote UE sends the identification information of the remote user equipment UE and a first indication to the session management function network element, where the first indication is used to indicate a request to switch the transmission path of the remote UE;

The remote UE receives a fifth address from the session management function network element, where the fifth address is used for data transmission between the remote UE and the user plane function network element.
The method according to claim 35, wherein the method further comprises:

The remote UE binds the fifth address with a sixth address, and the sixth address is used to transmit data between the remote UE and the relay UE before the transmission path of the remote UE is switched.
The method according to claim 35, wherein the method further comprises:

The remote UE replaces the sixth address with the fifth address, and the sixth address is used to transmit data between the remote UE and the relay UE before the transmission path of the remote UE is switched.
A method for realizing business continuity, which is characterized in that it includes:

The session management function network element allocates a seventh address to the remote UE, where the seventh address is used to transmit data of the remote UE between the user plane function network element and the server;

The session management function network element configures the user plane function network element with a first mapping relationship between the seventh address and a first address, and the first address is used to transmit the For data of the remote UE, the user plane function network element is a node on the first transmission path;

When the remote UE switches from the first transmission path to the second transmission path, the session management function network element configures the second address between the seventh address and the second address to the user plane function network element. In the mapping relationship, the second address is used to transmit data of the remote UE on the second transmission path, and the user plane function network element is a node on the second transmission path.
The method according to claim 38, wherein the first address is used to transmit data of the remote UE on the first transmission path, comprising:

The first address is used to transmit data of the remote UE between the user plane function network element and a first relay UE, and the first relay UE is a node on the first transmission path.
The method according to claim 39, wherein the second address is used to transmit data of the remote UE on the second transmission path, comprising:

The second address is used to transmit data of the remote UE between the user plane function network element and a second relay UE, and the second relay UE is a node on the second transmission path; or ,

The second address is used to transmit data of the remote UE between the user plane function network element and the remote UE, and the remote UE is a node on the second transmission path.
The method according to claim 38, wherein the first address is used to transmit data of the remote UE on the first transmission path, comprising:

The first address is used to transmit data of the remote UE between the user plane function network element and the remote UE, and the remote UE is a node on the first transmission path.
The method according to claim 41, wherein the second address is used to transmit data of the remote UE on the second transmission path, comprising:

The second address is used to transmit data of the remote UE between the user plane function network element and a second relay UE, and the second relay UE is a node on the second transmission path.
A method for realizing business continuity, which is characterized in that it includes:

The first user plane function network element receives a second message from the session management function network element, the second message includes a first address, and the first address is used for the first user before the transmission path of the remote user equipment UE is switched The plane function network element transmits the data of the remote UE;

The first user plane function network element transmits the data of the remote UE according to the mapping relationship between the first address and the third transmission channel, and the third transmission channel is the second user plane function network element and the A transmission channel between first user plane function network elements, and the second user plane function network element is a user plane function network element connected to the remote UE after the transmission path of the remote UE is switched.
The method according to claim 43, wherein the first address is used for the first user plane function network element to transmit the data of the remote UE before the transmission path of the remote UE is switched, comprising:

The first address is used to transmit data of the remote UE between the first user plane function network element and the first relay UE before the transmission path of the remote UE is switched, and the first relay UE is The relay UE that the remote UE is connected to before the remote UE transmission path is switched; or,

The first address is used to transmit the data of the remote UE between the first user plane function network element and the remote UE before the transmission path of the remote UE is switched.
A method for realizing business continuity, which is characterized in that it includes:

The first user plane function network element receives a second message from the session management function network element, the second message includes a first address and a second address, and the first address is used to switch the transmission path of the remote user equipment UE The first user plane function network element transmits the data of the remote UE, and the second address is used to transmit the data of the remote UE after the transmission path of the remote UE is switched. ；

The first user plane function network element transmits the data of the remote UE according to the mapping relationship between the first address, the second address, and a third transmission channel, where the third transmission channel is The transmission channel between the second user plane function network element and the first user plane function network element.
The method according to claim 45, wherein the first address is used to transmit the data of the remote UE by the second user plane function network element before the transmission channel of the remote UE is switched, comprising:

The first address is used to transmit data of the remote UE between the first user plane function network element and the first relay UE before the transmission path of the remote UE is switched, and the first relay UE is The relay UE that the remote UE is connected to before the remote UE transmission path is switched; or,

The first address is used to transmit the data of the remote UE between the first user plane function network element and the remote UE before the transmission path of the remote UE is switched.
The method according to claim 45 or 46, wherein the first user plane function network element transmitting the data of the remote UE according to the mapping relationship comprises:

Receiving, by the first user plane function network element, a first data packet from the second user plane function network element through the third transmission channel, the first data packet including the second address;

The first user plane function network element uses the first address to encapsulate the first data packet according to the mapping relationship to obtain a second data packet;

The first user plane function network element sends the second data packet to the network server.
The method according to any one of claims 45 to 47, wherein the first user plane function network element transmitting the data of the remote UE according to the mapping relationship comprises:

Receiving, by the first user plane function network element, a third data packet from the network server, the third data packet including the first address;

The first user plane function network element uses the second address to encapsulate the third data packet according to the mapping relationship to obtain the encapsulated fourth data packet;

The first user plane function network element sends the fourth data packet to the second user plane function network element through the third transmission channel.
A method for realizing business continuity, which is characterized in that it includes:

The second user plane function network element receives a third message from the session management function network element, the third message includes a first address, and the first address is used for the first user before the transmission path of the remote user equipment UE is switched The plane function network element transmits the data of the remote UE;

The second user plane function network element transmits the data of the remote UE according to the mapping relationship between the first address, the second transmission channel, and the third transmission channel, and the second transmission channel is the remote After the transmission path of the end UE is switched, the transmission channel between the second user plane and the remote UE, the third transmission channel is one of the second user plane function network element and the first user plane function network element Transmission channel between.
The method according to claim 49, wherein the first address is used for the second user plane function network element to transmit the data of the remote UE before the transmission channel of the remote UE is switched, comprising:

The first address is used to transmit data of the remote UE between the first user plane function network element and the first relay UE before the transmission channel of the remote UE is switched, and the first relay UE is The relay UE that the remote UE is connected to before the remote UE transmission channel is switched; or,

The first address is used to transmit the data of the remote UE between the first user plane function network element and the remote UE before the transmission channel of the remote UE is switched.
The method according to claim 49 or 50, wherein the second user plane function network element transmitting the data of the remote UE according to the mapping relationship comprises:

Receiving, by the second user plane function network element, a first data packet through the second transmission channel, the first data packet including the first address;

The second user plane function network element sends the first data packet to the first user plane function network element through the third transmission channel according to the mapping relationship.
The method according to any one of claims 49 to 51, wherein the second user plane function network element transmitting the data of the remote UE according to the mapping relationship comprises:

Receiving, by the second user plane function network element, a third data packet from the first user plane function network element through the third transmission channel, the third data packet including the first address;

The second user plane function network element sends the third data packet through the second transmission channel according to the mapping relationship.
A method for realizing business continuity, which is characterized in that it includes:

The second user plane function network element receives a third message from the session management function network element, the third message includes a second address, and the second address is used for the second user after the transmission path of the remote user equipment UE is switched The plane function network element transmits the data of the remote UE;

The second user plane function network element transmits the data of the remote UE according to the mapping relationship between the second address, the second transmission channel and the third transmission channel, and the second transmission channel is the remote After the transmission path of the end UE is switched, the transmission channel between the second user plane and the remote UE, the third transmission channel is one of the second user plane function network element and the first user plane function network element Transmission channel between.
The method according to claim 53, wherein the second user plane function network element transmitting the data of the remote UE according to the mapping relationship comprises:

Receiving, by the second user plane function network element, a first data packet through the second transmission channel, the first data packet including the first address;

The second user plane function network element sends the first data packet to the first user plane function network element through the third transmission channel according to the mapping relationship.
The method according to any one of claims 53 to 54, wherein the second user plane function network element transmitting the data of the remote UE according to the mapping relationship comprises:

Receiving, by the second user plane function network element, a third data packet from the first user plane function network element through the third transmission channel, the third data packet including the first address;

The second user plane function network element sends the third data packet through the second transmission channel according to the mapping relationship.
A method for realizing business continuity, which is characterized in that it includes:

The second session management function network element receives a first message from a remote user equipment UE, where the first message includes identification information of the remote UE connected to the relay UE;

The second session management function network element configures the mapping relationship between the first address and the second address to the second user plane function network element, where the first address is used for the first address before the transmission path of the remote UE is switched. A user plane function network element transmits the data of the remote UE, and the second address is used for the second user plane function network element to transmit the data of the remote UE after the transmission path of the remote UE is switched;

The second session management function network element requests the first session management function network element to establish a fourth transmission channel, and the first session management function network element serves the remote UE before the transmission path is switched. For the session management function network element of the remote UE, the fourth transmission channel is a transmission channel between the first user plane function network element and the second user plane function network element.
The method according to claim 56, further comprising:

After the context information of the remote UE on the second session management function network element is deleted, notify the first session management function network element to release the first address.
A method for realizing business continuity, which is characterized in that it includes:

The unified data management network element receives the identifier of the remote user equipment UE and the identifier of the first session management function network element from the first session management function network element, and the first session management function network element is a transmission of the remote UE A session management function network element serving the remote UE before path switching;

The unified data management network element receives the identifier of the remote UE from the second session management function network element, and the second session management function network element serves the remote UE after the transmission path of the remote UE is switched. The session management function network element of the end UE;

The unified data management network element sends the identifier of the first session management function network element to the second session management function network element.
A communication device, characterized in that it includes at least one processor, the at least one processor is connected to a memory, and the at least one processor is used to read and execute a program stored in the memory, so that the device executes The method of any one of claims 1-11, 17-25, 33-34, 38-42, or 56-57.
A communication device, characterized in that it includes at least one processor, the at least one processor is connected to a memory, and the at least one processor is used to read and execute a program stored in the memory, so that the device executes The method of any one of claims 12-16, 26-27, 43-44, 45-48, 49-52, or 53-55.
A communication device, characterized in that it includes at least one processor, the at least one processor is connected to a memory, and the at least one processor is used to read and execute a program stored in the memory, so that the device executes The method of any one of claims 28-32.
A communication device, characterized in that it includes at least one processor, the at least one processor is connected to a memory, and the at least one processor is used to read and execute a program stored in the memory, so that the device executes The method of any one of claims 35-37.
A communication device, characterized in that it includes at least one processor, the at least one processor is connected to a memory, and the at least one processor is used to read and execute a program stored in the memory, so that the device executes The method of claim 58.
A chip, characterized in that the chip is coupled with a memory, and is used to read and execute program instructions stored in the memory to implement the method according to any one of claims 1-58.
A communication system, comprising: a session management function network element that executes the method according to any one of claims 1-11 and a user plane function network element that executes the method according to any one of claims 12-16 Yuan.
A communication system, comprising: a session management function network element that executes the method according to any one of claims 17-25, and a user plane function network element that executes the method according to any one of claims 26-27 And any one of the relay user equipment UEs performing the method according to any one of claims 28-32.
A computer-readable storage medium, wherein the computer-readable storage medium stores computer instructions, which when run on a computer, cause the computer to execute the method according to any one of claims 1-58.
A computer program product, characterized in that, when the computer program product is called by a computer, the computer executes the method according to any one of claims 1-58.