CN114697999A

CN114697999A - Redundant path creating method, device and system

Info

Publication number: CN114697999A
Application number: CN202011578654.4A
Authority: CN
Inventors: 周汉; 胡伟华; 李汉成
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2020-12-28
Filing date: 2020-12-28
Publication date: 2022-07-01
Also published as: WO2022143395A1

Abstract

The embodiment of the application provides a method, a device and a system for creating a redundant path, which are used for ensuring the reliability of communication while saving the cost of a terminal and reducing network deployment. The redundant path creating method comprises the following steps: a terminal device 10 receives a message 30 from a user plane function 20, the terminal device 10 serving a terminal device 11; the terminal device 10 receives the message 30 from the terminal device 12; the terminal device 10 de-duplicates the message 30 from the user plane function 20 and the message 30 from the terminal device 12; the terminal device 10 sends the deduplicated message 30 to the terminal device 11.

Description

Redundant path creating method, device and system

Technical Field

The present application relates to the field of wireless communications technologies, and in particular, to a method, an apparatus, and a system for creating a redundant path.

Background

In the related art, most terminal devices are connected to a wireless network in a linear topology, in the linear topology, a first node on a production line is connected to the wireless network, and other terminal devices on the production line are connected to the wireless network through the first node. If the network quality between the head node and the wireless network is unstable, links between other terminal devices on the production line and the wireless network will fail.

The terminal equipment can also be accessed to the wireless network by adopting a star topology or a tree topology, and in the star topology or the tree topology, each terminal equipment on a production line can be directly connected with the wireless network. If the forwarding rule is not changed, the Master of the industrial application server only sends one message, then the message is forwarded in each terminal device according to the forwarding rule of the linear topology, and if the network quality between the first terminal device receiving the message and the wireless network is unstable, links between other terminal devices and the wireless network also fail. If the forwarding rule is changed, the network device is required to unpack the message sent by the Master and then forward the unpacked message to each terminal device, which may waste the processing resources of the network device, and the network device does not necessarily have the function of unpacking the message, thereby providing a higher requirement for the wireless network and increasing the difficulty of network deployment.

Therefore, when the terminal device accesses the wireless network, the reliability of communication cannot be guaranteed, the processing resources of the network device are wasted, and the difficulty of network deployment is increased.

Disclosure of Invention

The embodiment of the application provides a method, a device and a system for creating a redundant path, which are used for ensuring the reliability of communication while saving the cost of a terminal and reducing the difficulty of network deployment.

In a first aspect, a redundant path creation method is provided, including: a terminal device 10 receives a message 30 from a user plane function 20, the terminal device 10 serving a terminal device 11; the terminal device 10 receives the message 30 from the terminal device 12; the terminal device 10 de-duplicates the message 30 from the user plane function 20 and the message 30 from the terminal device 12; the terminal device 10 sends the message 30 after the duplication removal to the terminal device 11.

In the industrial network topology, all terminal devices can access the wireless network through the terminal devices with the network access capability, and the terminal devices with the network access capability can transparently forward the message, so that mutual backup and load sharing of wireless connection are realized. Under the existing communication system architecture, the actual networking model of the industrial Ethernet protocol is combined, so that the communication reliability is guaranteed while the terminal cost is saved and the network deployment difficulty is reduced.

In a possible design, the terminal device 10 may further receive a response 31 from the terminal device 11, where the response 31 corresponds to the deduplicated packet 30; the terminal device 10 sends a response 32 to the terminal device 12, the response 32 corresponding to the message 30 from the terminal device 12.

In this design, the terminal device with network access capability may also forward a response (i.e., an uplink packet) to improve the reliability of communication.

In a possible design, if a fault occurs between the terminal device 10 and the user plane function 20, the terminal device 10 may further receive a message 35 from the terminal device 12, and send the message 35 to the terminal device 11.

In the design, when a data transmission link fails, the detection and the positioning of the failure can be realized, and different redundancy transmission strategies are implemented according to different failure points, so that the reliability of communication is further ensured.

In a possible design, the terminal device 10 may further receive first information from the session management function 21, where the first information indicates that the message from the user plane function 20 and the message from the terminal device 12 are to be deduplicated and then sent to the terminal device 11.

In this design, the session management function 21 may instruct the terminal device 10 to perform deduplication on multiple identical received messages, so as to ensure reliability of communication even when the industrial topology network does not support redundant transmission.

In one possible design, the terminal device 10 may further receive second information from the session management function 21, the second information indicating that a transmission path with the terminal device 12 is established.

In this design, when the industrial topology network does not support redundant transmission, the session management function 21 may instruct the terminal device 10 to establish a transmission path with the terminal device 12 to ensure reliability of communication when the industrial topology network does not support redundant transmission.

In a second aspect, a method for creating a redundant path is provided, the method including: the session management function 21 acquires the terminal device 11 served by the terminal device 10; the session management function 21 obtains the terminal device 14 served by the terminal device 12; the session management function 21 determines that there is a correspondence between the terminal device 10 and the terminal device 12; the session management function 21 sends a forwarding rule to the user plane function 20, where the forwarding rule indicates that a message is sent to the terminal device 11 through the terminal device 10 and a message is sent to the terminal device 14 through the terminal device 12.

The session management function may create a reliable redundant transmission path for the plurality of terminal devices having the corresponding relationship, and the plurality of terminal devices having the corresponding relationship have a reliable backup relationship, and the plurality of terminal devices having the reliable backup relationship may be integrated in one industrial terminal device or may be respectively deployed on a plurality of industrial terminals, thereby ensuring reliable transmission when the terminal devices access the wireless network.

In one possible design, the forwarding rule further indicates that the packet is duplicated.

In the design, when the industrial topological network does not support redundant transmission, the session management function can instruct the user plane function to copy the message so as to ensure the reliability of communication.

In a possible design, the session management function 21 may further send, to the terminal device 10, first information indicating that the message from the user plane function 20 and the message from the terminal device 12 are to be deduplicated and then sent to the terminal device 11.

In one possible design, the session management function 21 may further send second information to the terminal device 10, where the second information indicates that a transmission path with the terminal device 12 is established.

Optionally, the session management function 21 may further send third information to the terminal device 12, where the third information indicates establishment of a transmission path with the terminal device 10.

In one possible design, when the session management function 21 obtains the terminal device 11 served by the terminal device 10, the session management function 21 may receive information from the terminal device 11 of the terminal device 10.

In this design, the terminal device 10 may report information of the terminal device 11 served by the terminal device to the session management function 21, so that the session management function 21 obtains information of the industrial terminal served by the terminal device 10.

In one possible design, when the session management function 21 obtains the terminal device 14 served by the terminal device 12, the session management function 21 receives information from the terminal device 14 of the terminal device 12.

In this design, the terminal device 12 may report information of the terminal device 14 that it serves to the session management function 21 so that the session management function 21 acquires information of the industrial terminal that the terminal device 12 serves.

In a possible design, when the session management function 21 determines that there is a correspondence between the terminal device 10 and the terminal device 12, the session management function 21 obtains subscription data of the terminal device 10, where the subscription data of the terminal device 10 indicates that there is a correspondence with the terminal device 12; and/or the session management function 21 obtains the subscription data of the terminal device 12, where the subscription data indication of the terminal device 12 has a corresponding relationship with the terminal device 10.

In this design, the session management function 21 may obtain the subscription data of the terminal device 10 and/or the subscription data of the terminal device 12, and determine that the terminal device 10 and the terminal device 12 have a reliable backup relationship according to an indication of the subscription data, so as to create a reliable redundant transmission path for the terminal device 10 and the terminal device 12.

In a third aspect, a redundant path transmission method is provided, where the method includes: the terminal device 11 receives the message 30 from the terminal device 10; the terminal device 11 receives the message 30 from the terminal device 12; the terminal device 11 sends a response 33 to the terminal device 10, where the response 33 corresponds to the message 30 from the terminal device 10; the terminal device 11 sends a response 34 to the terminal device 12, where the response 34 corresponds to the message 30 from the terminal device 12.

In an industrial network topology, the terminal device 11 can access a wireless network through the terminal device 10 and the terminal device 12 with network access capability, so that the reliability of communication is guaranteed while the terminal cost is saved and the network deployment is reduced.

In one possible design, after the terminal device 11 receives the message 30 from the terminal device 10 and receives the message 30 from the terminal device 12, the method further includes:

the terminal device 11 de-duplicates the packet 30 from the terminal device 10 and the packet 30 from the terminal device 12;

the terminal device 11 sends a response 38 to the terminal device 10, where the response 38 corresponds to the deduplicated packet 30.

In one possible design, the method further includes:

the terminal device 11 copies the response 38, and sends a response 39 obtained by copying the response 38 to the terminal device 12.

The data in the response 39 may be partially identical to the data in the response 38, or may be all identical.

In one possible embodiment, the terminal 11 may also receive a message 35 from the terminal 12 if a fault occurs between the terminal 10 and the user plane function 20 or if the terminal 10 fails.

In a fourth aspect, a redundant path transmission method is provided, the method including: the terminal device 11 receives the message 30 from the terminal device 10; the terminal device 11 receives the message 30 from the terminal device 12 through the terminal device 10; the terminal device 11 sends a response 36 to the terminal device 10, where the response 36 corresponds to the message 30 from the terminal device 10; the terminal device 11 sends a response 37 to the terminal device 12 through the terminal device 10, where the response 37 corresponds to the packet 30 from the terminal device 12.

In an industrial network topology, the terminal device 11 can access a wireless network through the terminal device 10 and the terminal device 12 with network access capability, so that the reliability of communication is guaranteed while the terminal cost is saved and the difficulty of network deployment is reduced.

In a fifth aspect, a communication apparatus is provided, which may be a terminal device 10, and includes a processing unit and a transceiving unit;

the transceiver unit is configured to receive a message 30 from a user plane function 20, and the communication device serves a terminal device 11; receiving the message 30 from the terminal device 12;

the processing unit is configured to perform deduplication on the packet 30 from the user plane function 20 and the packet 30 from the terminal device 12;

the transceiver unit is further configured to send the deduplicated message 30 to the terminal device 11.

In a possible design, the transceiver unit is further configured to receive a response 31 from the terminal device 11, where the response 31 corresponds to the deduplicated packet 30; sending a response 32 to the terminal device 12, the response 32 corresponding to the message 30 from the terminal device 12.

In a possible design, the transceiver unit is further configured to receive a message 35 from the terminal device 12 and send the message 35 to the terminal device 11 if a failure occurs between the communication apparatus and the user plane function 20.

In a possible design, the transceiver unit is further configured to receive first information from the session management function 21, where the first information indicates that the message from the user plane function 20 and the message from the terminal device 12 are to be deduplicated and then sent to the terminal device 11.

In a possible design, the transceiver unit is further configured to receive second information from the session management function 21, where the second information indicates that a transmission path between the terminal device 12 and the terminal device is established.

A sixth aspect provides a communication apparatus, which may be a session management function 21, comprising a processing unit and a transceiving unit;

the receiving and sending unit is used for acquiring the terminal equipment 11 served by the terminal equipment 10; a terminal device 14 that obtains services of the terminal device 12;

the processing unit is used for determining that the terminal equipment 10 and the terminal equipment 12 have a corresponding relation;

the transceiver unit is further configured to send a forwarding rule to a user plane function 20, where the forwarding rule indicates that a message is sent to the terminal device 11 through the terminal device 10 and a message is sent to the terminal device 14 through the terminal device 12.

In a possible design, the transceiver unit is further configured to send, to the terminal device 10, first information indicating that a message from the user plane function 20 and a message from the terminal device 12 are to be deduplicated and then sent to the terminal device 11.

In a possible design, the transceiver unit is further configured to send second information to the terminal device 10, where the second information indicates establishment of a transmission path with the terminal device 12.

In one possible embodiment, the transceiver unit is specifically configured to receive information from a terminal device 11 of the terminal devices 10.

In one possible embodiment, the transceiver unit is specifically configured to receive information from a terminal device 14 of the terminal devices 12.

In a possible design, the processing unit is specifically configured to obtain subscription data of the terminal device 10, where the subscription data of the terminal device 10 indicates that there is a corresponding relationship with the terminal device 12; and/or obtaining subscription data of the terminal device 12, where the subscription data of the terminal device 12 indicates that there is a corresponding relationship with the terminal device 10.

In a seventh aspect, a communication apparatus is provided, which may be a terminal device 11, and includes a processing unit and a transceiver unit;

the transceiver unit is configured to receive a message 30 from the terminal device 10; receiving the message 30 from the terminal device 12;

the processing unit is configured to determine the packet 30;

the transceiver unit is further configured to send a response 33 to the terminal device 10, where the response 33 corresponds to the message 30 from the terminal device 10; sending a response 34 to the terminal device 12, the response 34 corresponding to the message 30 from the terminal device 12.

In a possible design, the processing unit is further configured to duplicate the packet 30 from the terminal device 10 and the packet 30 from the terminal device 12;

the transceiver is further configured to send a response 38 to the terminal device 10, where the response 38 corresponds to the deduplicated message 30.

In one possible design, the processing unit is further configured to copy the response 38;

the transceiver unit is further configured to send a response 39 obtained by copying the response 38 to the terminal device 12.

In a possible design, the transceiver unit is further configured to receive a message 35 from the terminal device 12 if a failure occurs between the terminal device 10 and the user plane function 20 or if the terminal device 10 fails.

In an eighth aspect, a communication apparatus is provided, which may be a terminal device 11, and includes a processing unit and a transceiver unit;

the transceiver unit is configured to receive a message 30 from the terminal device 10; receiving the message 30 from the terminal device 12 through the terminal device 10;

the processing unit is configured to determine the packet 30;

the transceiver is further configured to send a response 36 to the terminal device 10, where the response 36 corresponds to the message 30 from the terminal device 10; sending a response 37 to the terminal device 12 by the terminal device 10, the response 37 corresponding to the message 30 from the terminal device 12.

A ninth aspect provides a communications device having functionality to implement a method as any of the possible designs of the first or second or third or fourth aspects above. The function can be realized by hardware, and can also be realized by executing corresponding software by hardware. The hardware or software includes one or more modules corresponding to the functions described above.

In a tenth aspect, there is provided a communication apparatus comprising: a transceiver, a processor, and a memory; a transceiver for transceiving data or information, the memory for storing computer-executable instructions, the processor for executing the computer-executable instructions stored by the memory when the apparatus is operating, to cause the apparatus to perform a method as implemented in any possible design of the first aspect or the second aspect or the third aspect or the fourth aspect as described above.

In an eleventh aspect, there is provided a communication apparatus comprising: comprising means or units for performing the steps of any of the possible designs of the first or second or third or fourth aspects above.

In a twelfth aspect, there is provided a communications device comprising a processor and an interface circuit, the processor being configured to communicate with other devices via the interface circuit and to perform the method as provided by any of the possible designs of the first, second, third or fourth aspects above. The processor includes one or more.

In a thirteenth aspect, there is provided a communications device comprising a processor configured to invoke a program stored in a coupled memory to perform a method as in any possible design of the first or second or third or fourth aspects above. The memory may be located within the device or external to the device. And the processor includes one or more.

In a fourteenth aspect, there is provided a computer readable storage medium having stored therein instructions, which when run on a computer, cause the processor to perform the method of any of the possible designs of the first or second or third or fourth aspects above.

In a fifteenth aspect, there is provided a computer program product comprising instructions which, when run on a computer, cause the computer to perform the method of any of the possible designs of the first or second or third or fourth aspects described above.

In a sixteenth aspect, a chip system is provided, including: a processor configured to perform a method as any one of the above first, second, third or fourth aspects may be designed for.

A seventeenth aspect provides a chip system comprising a transceiver for implementing functions in any of the possible design methods of the first or second or third or fourth aspects, e.g. for receiving or transmitting data and/or information related to the methods. In one possible design, the system-on-chip further includes a memory for storing program instructions and/or data. The chip system may be formed by a chip, or may include a chip and other discrete devices.

In an eighteenth aspect, there is provided a communication system comprising a session management function 21 performing the method of any possible design in the second aspect, and the user plane function 20 receiving the forwarding rules from the session management function 21.

Optionally, the communication system may further include a terminal device 10, a terminal device 12, and a terminal device 11, which perform any of the methods as may be designed in the first aspect, and perform any of the methods as may be designed in the third aspect or the fourth aspect.

For technical effects that can be achieved by any one of the fifth aspect to the eighteenth aspect and any one of the possible implementations of any one of the fifth aspect to the eighteenth aspect, please refer to the description of the technical effects that can be brought by any one of the aspects, and repeated description is omitted here.

Drawings

Fig. 1 and 11 are schematic diagrams of a network architecture;

FIG. 2 is an Ethernet frame format;

FIG. 3 is a schematic diagram of a two-layer exchange;

fig. 4, fig. 15, and fig. 16 are schematic diagrams of forwarding logic of a user plane function;

FIG. 5 is an Ethernet message frame structure;

fig. 6 and 7 are schematic diagrams of message forwarding;

FIG. 8 is a schematic diagram of a network architecture;

FIG. 9, FIG. 10, FIG. 13, FIG. 17, FIG. 18, FIG. 19 are schematic diagrams of an industrial network topology;

FIGS. 12 and 14 are schematic diagrams illustrating a redundant path creation process;

fig. 20 and 21 are schematic diagrams of a communication device.

Detailed Description

The present application will be described in further detail below with reference to the accompanying drawings.

This application is intended to present various aspects, embodiments or features around a system that may include a number of devices, components, modules, and the like. It is to be understood and appreciated that the various systems may include additional devices, components, modules, etc. and/or may not include all of the devices, components, modules etc. discussed in connection with the figures. Furthermore, a combination of these schemes may also be used.

In addition, in the embodiments of the present application, the word "exemplary" is used to mean serving as an example, instance, or illustration. Any embodiment or design described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments or designs. Rather, the term using examples is intended to present concepts in a concrete fashion.

The network architecture and the service scenario described in the embodiment of the present application are for more clearly illustrating the technical solution of the embodiment of the present application, and do not form a limitation on the technical solution provided in the embodiment of the present application, and as a person of ordinary skill in the art knows that along with the evolution of the network architecture and the appearance of a new service scenario, the technical solution provided in the embodiment of the present application is also applicable to similar technical problems.

Some terms of the embodiments of the present application are explained below to facilitate understanding by those skilled in the art.

1) The terminal device includes, but is not limited to, a User Equipment (UE) and an industrial terminal in this embodiment. In order to realize the access of the industrial terminal to the wireless network, a wireless module can be installed in the industrial terminal, and the industrial terminal can communicate with network equipment through the wireless module. Wherein the UE may be installed in the industrial terminal as a wireless module, and in the embodiment of the present application, except for specific description, the concepts of the UE and the wireless module may be used alternatively.

In a wireless network, a UE is a device having a radio transceiving function, and may communicate with one or more Core Network (CN) devices (or may also be referred to as core devices) through an access network device (or may also be referred to as an access device) in a Radio Access Network (RAN).

For example, a user device can also be called an access terminal, subscriber unit, subscriber station, mobile, remote station, remote terminal, mobile device, user terminal, user agent, or user equipment, etc. User equipment may be deployed on land, including indoors or outdoors, hand-held or vehicle-mounted; can also be deployed on the water surface (such as a ship and the like); and may also be deployed in the air (e.g., airplanes, balloons, satellites, etc.). The user equipment may be a cellular telephone (cellular phone), a cordless telephone, a Session Initiation Protocol (SIP) phone, a smart phone (smart phone), a mobile phone (mobile phone), a Wireless Local Loop (WLL) station, a Personal Digital Assistant (PDA), or the like. Alternatively, the user equipment may also be a handheld device with wireless communication functionality, a computing device or other device connected to a wireless modem, an in-vehicle device, a wearable device, a drone device or internet of things, a terminal in an in-vehicle network, a terminal of any modality in a fifth generation mobile communication (5th-generation, 5G) network and future networks, a relay user equipment, a terminal in a PLMN for future evolution, or the like. The relay user equipment may be, for example, a 5G home gateway (RG). For example, the user equipment may be a Virtual Reality (VR) terminal, an Augmented Reality (AR) terminal, a wireless terminal in industrial control (industrial control), a wireless terminal in self driving (self driving), a wireless terminal in remote medical (remote medical), a wireless terminal in smart grid, a wireless terminal in transportation safety, a wireless terminal in smart city (smart city), a wireless terminal in smart home (smart home), and the like. The embodiment of the present application does not limit the type or category of the terminal device.

2) The network device refers to a device that can provide a wireless access function for a terminal. Among other things, the network device may support at least one wireless communication technology, such as Long Term Evolution (LTE), New Radio (NR), Wideband Code Division Multiple Access (WCDMA), and so on.

For example, the network device may comprise an access network device. Exemplary network devices include, but are not limited to: a next generation base station or a next generation node B (gbb) in the 5G network, an evolved node B (eNB), a Radio Network Controller (RNC), a Node B (NB), a Base Station Controller (BSC), a Base Transceiver Station (BTS), a home base station (e.g., home evolved node B or home node B, HNB), a Base Band Unit (BBU), a Transmission and Reception Point (TRP), a Transmission Point (TP), a mobile switching center, a small station, a micro station, and the like. The network device may also be a wireless controller, a Centralized Unit (CU), and/or a Distributed Unit (DU) in a Cloud Radio Access Network (CRAN) scenario, or the network device may be a relay station, an access point, a vehicle-mounted device, a terminal, a wearable device, and a network device in future mobile communication or a network device in a public mobile land network (PLMN) for future evolution, and the like.

As another example, the network device may include a Core Network (CN) device, which may include, for example, an AMF or the like.

As another example, a network device may include user plane functions (e.g., UPF), control plane functions (e.g., SMF), and so on.

3) Industrial ethernet networks, also known as industrial networks, are networks that use a particular industrial protocol encapsulated in an ethernet protocol. The industrial ethernet protocols employed by the industrial ethernet network include, but are not limited to, the following: modbus TCP/IP, EtherCat, EtherNet/IP, and Profinet. Industrial ethernet networks have penetrated plant shops and become the primary means of communication for automation and control systems due to their inherent reliability, high performance and interoperability.

The industrial Ethernet mainly comprises the following parts: master (Master) device, network device and (Slave) Slave device. Generally, the Master device may issue a message to the Slave device through the network device, and the Slave device may reply a response to the Master device through the network device. The Master device is an industrial application server, and may also be referred to as a Controller. The network device may include user plane functionality and control plane functionality. The Slave device is an industrial terminal, a wireless module is installed in the industrial terminal, and the Slave device may also be referred to as a device (device), or simply referred to as D.

The Slave devices in the industrial ethernet network may or may not support redundant transport. When the Slave device in the industrial ethernet network supports redundant transmission, the Master device in the industrial ethernet network may support redundant transmission, or may not support redundant transmission. When the Slave device in the industrial ethernet network does not support redundant transmission, the Master device in the industrial ethernet network may support redundant transmission, or may not support redundant transmission. Whether the Slave device supports redundant transmission can be regarded as whether the Slave device supports an industrial reliability protocol. Whether the Master device supports redundant transmission can be regarded as whether the Master device supports an industrial reliability protocol.

It can be understood that the redundant path creation method provided in the embodiment of the present application is mainly applied to an industrial ethernet network, and may also be applied to other networks, which is not limited thereto.

"and/or" in the present application, describing an association relationship of associated objects, means that there may be three relationships, for example, a and/or B, may mean: a exists alone, A and B exist simultaneously, and B exists alone. The character "/" generally indicates that the former and latter associated objects are in an "or" relationship.

The plural in the present application means two or more.

In addition, it is to be understood that the terms first, second, etc. in the description of the present application are used for distinguishing between the descriptions and not necessarily for describing a sequential or chronological order.

The technical scheme of the embodiment of the application can be applied to various communication systems. For example, the technical solution provided in the embodiment of the present application may be applied to an LTE system, an LTE Frequency Division Duplex (FDD) system, an LTE Time Division Duplex (TDD), a Universal Mobile Telecommunications System (UMTS), a Worldwide Interoperability for Microwave Access (WiMAX) communication system, a 5G communication system, or NR, and other future communication systems such as 6G.

The 3rd Generation partnership project (3 GPP) standards group established a Next Generation mobile communication network architecture (Next Generation System) called 5G network architecture in the year 2016. The 5G network architecture supports radio technologies (e.g., LTE, 5G RAN, etc.) defined by the 3GPP standard group, and access modes such as a fixed network access the core network side.

In order to facilitate understanding of the embodiments of the present application, an application scenario used in the present application is described with reference to a 5G network architecture shown in fig. 1 as an example. Fig. 1 shows a 5G network architecture based on a service architecture in a non-roaming scenario defined in the 3GPP standardization process. The network architecture may include: a terminal device portion, a network device portion, and a Data Network (DN) portion. In particular, the present invention relates to a process in which a terminal device accesses a core network (or an operator network) through an access device, and performs protocol data communication after a packet data unit session (PDU session) is created.

The network device portion includes a network open function (NEF) 131, a network storage function (NRF) 132, a Policy Control Function (PCF) 133, a unified data management function (UDM) 134, AN authentication server function (AUSF) 136, AN AMF137, a Session Management Function (SMF) 138, a User Plane Function (UPF) 139, AN access network (access network, AN)140, a Network Slice Selection Function (NSSF) 141, and the like. In the above network device, the portion other than the access network 140 portion may be referred to as a core network portion.

The core network portion includes user plane functions and control plane functions. The user plane function is mainly responsible for forwarding of data packets, quality of service (QoS) control, accounting information statistics, and the like. The control plane function is mainly responsible for service flow interaction, and issuing a data packet forwarding strategy, a QoS control strategy and the like to the user plane function.

The data network DN 120, which may also be referred to as a Packet Data Network (PDN), may generally be deployed outside of an operator network, such as a third party network. Illustratively, the operator network may have access to a plurality of data network DNs 120, and a plurality of services may be deployed on data network DNs 120 to provide services such as data and/or voice for terminal device 110. The third party may be a service party other than the operator network and the terminal device 110, and may provide other services such as data and/or voice for the terminal device 110. The specific expression form of the third party may be determined according to an actual application scenario, and is not limited herein.

The Application Function (AF) 135 may or may not be affiliated with the operator network. However, typically the AF is affiliated with a third party and not with the operator network, but has an agreement with the operator network. The AF is used for providing functional network elements of various service services, and can support functions of influencing data routing through applications, access network opening function NEF, interaction with a policy framework for policy control, and the like.

By way of example, a brief introduction of network functions in an operator network follows.

AN 140, also called a Radio (Radio) AN, is a sub-network of AN operator network, and is AN implementation system between a service node (or network function) and terminal device 110 in the operator network. Terminal device 110 accesses the operator network, first through AN 140, and then connects to a service node in the operator network through AN 140. The AN 140 in the embodiment of the present application may refer to AN access network itself, or may refer to AN access network device, which is not differentiated herein. AN access network device is a device that provides a wireless communication function for terminal device 110, and may also be referred to as AN access device, AN (R) AN device, or a network device. The access network devices include, but are not limited to: gNB in a 5G system, eNB in an LTE system, RNC, NB, base station controller BSC, BTS, HNB, BBU, TRP, TP, small base station equipment (pico), mobile switching center, or network equipment in a future network, etc. It is understood that the present application is not limited to the specific type of access network device. In systems using different radio access technologies, the names of devices that function as access network devices may differ.

Optionally, in some deployments of the access device, the access device may include CUs and DUs.

The network open function NEF (which may also be referred to as a network open function entity) 131 is a control plane function provided by an operator, provides a framework, authentication and interface related to network capability opening, and passes information between a network function and other network functions in the 5G system. The network opening function NEF 131 opens an outbound bidirectional interface to the capability of the network of the third party in a secure manner. NEF network function 131 may act as a relay for communication with a network entity of a third party when other network functions (e.g., application function AF135, etc.) require network communication with the third party. NEF network function 131 may also act as a translation of the identity information of subscribers, as well as a translation of the identity information of third party's network functions. For example, when the NEF network function 131 transmits a subscriber permanent identifier (SUPI) of the subscriber from the PLMN to the third party, the SUPI may be translated into its corresponding subscription identifier (GPSI) for external public use. Conversely, the NEF network function 131 forwards external information to the PLMN network, preventing other network functions inside the PLMN from coming into direct contact with the outside.

The network storage function NRF 132, which is a control plane function provided by the operator, may be used to maintain real-time information of all network function services in the network.

Policy control function PCF 133 is a control plane function provided by an operator for generating and managing user, session, QoS flow handling policies. The method supports a unified strategy framework to manage network behaviors, provide strategy rules and subscription information related to strategy decision for other control functions and the like.

The unified data management UDM 134 is a control plane function provided by an operator, and is responsible for storing information such as security context (security context) and subscription data of a subscriber in a PLMN. The subscriber of the operator network may specifically be a subscriber using a service provided by the operator network, for example, a subscriber using a core card of a terminal device of china telecommunications, or a subscriber using a core card of a terminal device of china mobile, and the like. The security context may be, for example, data (cookie) or a token (token) stored on a local terminal device (e.g., a mobile phone). The subscription data of the subscriber may be a service associated with the core card of the terminal device, such as a traffic package of the core card of the mobile phone.

The authentication server function AUSF 136 is a control plane function provided by the operator and is typically used for a first-level authentication, i.e. a network authentication between the terminal device 110 (subscriber) and the operator network.

The access and mobility management function AMF137 is a control plane network function provided by the operator network, and is responsible for access control and mobility management of the terminal device 110 accessing the operator network, and includes functions such as mobility state management, allocating a temporary user identity, authenticating and authorizing a user, and the like.

The session management function SMF 138 is a control plane network function provided by the operator network, and is responsible for managing a Protocol Data Unit (PDU) session of the terminal device 110. A PDU session is a channel for transmitting PDUs, and a terminal device needs to transmit data to and from the DN 120 through the PDU session. The PDU session may be responsible for establishment, maintenance, deletion, etc. by the SMF 138. SMF 138 includes session-related functions such as session establishment, modification, and release, including tunnel maintenance between UPF139 and AN 140, selection and control of UPF139, Service and Session Continuity (SSC) mode selection, roaming, and the like.

The user plane function UPF139 is a gateway provided by the operator, which is a gateway for the operator's network to communicate with the DN 120. The UPF139 includes user plane related functions such as packet routing and transmission, packet detection, service usage reporting, QoS processing, lawful interception, uplink packet detection, downlink packet storage, and the like.

The network slice selection function NSSF141 is a control plane network function provided by the operator network, and is responsible for determining a network slice instance, selecting the AMF network function 137, and the like.

In fig. 1, Nnef, Nausf, Nnrf, Npcf, numm, Naf, Namf, Nsmf, nssf, N1, N2, N3, N4, and N6 are interface serial numbers. For example, the meaning of the above interface sequence number can be referred to the meaning defined in the 3GPP standard protocol, and the application does not limit the meaning of the above interface sequence number. For example, N1 is an interface between terminal device 110 and a core network control plane function, and is used to transfer Non Access Stratum (NAS) signaling. N2 is the communication interface between the access network device and the core network control plane function. N3 is a communication interface between an access network device and a core network user plane function for transmitting user data. N4 is a communication interface between the control plane function SMF and the user plane function UPF, for policy configuration and the like of the UPF. It should be noted that, in fig. 1, only the terminal device 110 is taken as an example for the UE, an interface name between each network function in fig. 1 is also only an example, and in a specific implementation, the interface name of the system architecture may also be other names, which is not limited in this application.

For convenience of description, in the embodiment of the present application, the session management function SMF 138 is abbreviated as SMF, and the unified data management UDM 134 is abbreviated as UDM, that is, in the embodiment of the present application, the AMF described later may be replaced by a mobility management network function, and the UDM may be replaced by unified data management. It will be appreciated that other network functions not shown are equally applicable to this alternative approach.

A network architecture (for example, a 5G network architecture) shown in fig. 1 adopts a service-based architecture and a general interface, a conventional network element function is split into a plurality of self-contained, self-managed, and reusable network function service modules based on a Network Function Virtualization (NFV) technology, a customized network function reconfiguration can be realized by flexibly defining a service module set, and a service flow is formed externally through a unified service call interface. The network architecture diagram shown in fig. 1 can be understood as a service-based 5G network architecture diagram in a non-roaming scenario. In the framework, different network functions are combined in order according to requirements of a specific scene, and customization of network capacity and service can be realized, so that special networks are deployed for different services, and 5G network slicing (network slicing) is realized. The network slicing technology can enable an operator to respond to customer requirements more flexibly and quickly, and flexible allocation of network resources is supported.

Ethernet sessions (e.g., ethernet PDU sessions) are supported in 5G networks, and the packets of the ethernet sessions are called ethernet frames/ethernet frames. Fig. 2 shows a possible ethernet frame format, where a Destination Address (DA) is a destination MAC address, a Source Address (SA) is a source MAC address, a Type (Type) is an ethertype, Data (Data) is a Data segment, and a Cyclic Redundancy Check (CRC) is a check bit. When the ethertype is 0x8100, it indicates that Virtual Local Area Network (VLAN) information is inserted, and includes a Priority field, a Control Format Indicator (CFI) word, and a VLAN Identification (ID) field, where the Priority field includes a class of service (class of service) value of 3 bits. There may be no VLAN Tag field or one or more VLAN Tag fields in the ethernet frame, as in fig. 2, which includes a VLAN Tag field including the inserted VLAN information.

The two-layer switching in the ethernet network belongs to link layer switching, and is based on Media Access Control (MAC) address forwarding, the switching device obtains a forwarding port by querying a MAC address learning table, and for an MAC address which is not recorded in the MAC address learning table, the switching device may forward the MAC address in a broadcast manner. As shown in fig. 3, which is a two-layer switching principle, the switch stores an MAC address learning table, records a correspondence between a user MAC address and a port, and if forwarding is based on a VLAN and a MAC address, the MAC address learning table may further include corresponding VLAN information. The MAC address learning table comprises MAC addresses such as MACA, MACB, MACC, MACD and the like, a port corresponding to the MACA address is a port 1, a port corresponding to the MACB address is a port 1, a port corresponding to the MACC address is a port 2, and a port corresponding to the MACD address is a port 2. When the switch receives the message with the destination address of MACD from the port 1, the switch queries the MAC learning table to acquire the port information corresponding to the MACD as the port 2, and then the message is sent out from the port 2. The entry of the MACD in the MAC address learning table may be learned when the port 2 receives a message with a source MAC address of the MACD, or may be obtained through configuration information.

The CU separation of the 4G network and the 5G network defines the forwarding logic of the user plane functions (e.g. UPF, gateway GW). As shown in fig. 4, a user plane function receives a packet, determines a Packet Forwarding Control Protocol (PFCP) session, determines a Forwarding Action Rule (FAR) specified in a matched FDR according to a Packet Detection Rule (PDR) of a priority in the determined PFCP session, and processes the received packet according to a policy in the FAR. When determining the PFCP session, the user plane function may determine the PFCP session after matching information such as a network instance (network instance) and an address of the terminal device according to an indication in the PDR. When the received message is processed according to the policy in the FAR, if the message is a downlink message, the user plane function adds a packet header according to the instructions in the FAR, such as according to forwarding behavior rules FARs, QoS Enforcement Rules (QERs), and Usage Reporting Rules (URRs), and sends the packet header to the terminal device.

Ethernet control automation technology (EtherCAT) is an ethernet-based bus system that allows ethernet to be used in automation applications. EtherCAT is applied to industrial ethernet networks, and the EtherCAT message may be based on ethernet encapsulation (for example, the ethertype is 0x88a4), or encapsulated in an IP message (for example, encapsulated in a User Datagram Protocol (UDP) message, and the destination port number of the UDP is 0x88a 4).

For industrial applications with little single traffic, the encapsulation efficiency may be low if the data destined for a single device is encapsulated using ethernet packets at a time. For example, a driver periodically sends 4 bytes of actual value and status information and simultaneously receives 4 bytes of command value and control word information, and even if the bus load is 100% (i.e., infinitesimal drive response time), the available data rate can only reach 4/84 ═ 4.8% (the minimum encapsulation and synchronization fields of ethernet packets, etc., add up to 84 bytes). And the EtherCAT collects a plurality of EtherCAT sub-messages in one EtherCAT message, thereby improving the transmission efficiency.

As an example, as shown in fig. 5, the EtherCAT is encapsulated in an Ethernet packet, where the Ethernet packet includes an Ethernet header (Ethernet header), an Ethernet data portion (Ethernet data), and a Frame Check Sequence (FCS), the Ethernet header occupies 14 bits (Byte), and the FCS occupies 4 bytes. The Ethernet data comprises an EtherCAT sub-message data Length (Length), a reserved bit (Res.), a Type (Type) and a plurality of EtherCAT sub-messages. The plurality of EtherCAT sub-messages comprise a first EtherCAT datagram (1)^stEtherCAT Datagram), second EtherCAT Datagram (2)^ndEtherCAT Datagram), … … n EtherCAT Datagram (n)^thEtherCAT Datagram). Each EtherCAT sub-packet includes a sub-packet Header (Datagram Header), an EtherCAT Data portion (Data), and a work counter (WKC). The sub-message header comprises information such as an addressing and reading-writing mode (Cmd), a frame code (Idx), Address information (Address), EtherCAT sub-message data area length (Len), a reserved bit (R), a frame cycle mark (C), a subsequent message mark (M), a status bit (IRQ) and the like.

The industrial Ethernet of the EtherCAT protocol comprises a Master device, a plurality of Slave devices and the like, network interfaces of the devices comprise a sending function and a receiving function, and various physical topologies can be realized through wired connection among the devices. The message forwarding always forwards on a linear path: after the message is sent out by the Master device, the message is forwarded between the Slave terminals and finally returned to the Master terminal. As shown in fig. 6, the EtherCAT network includes a Master device and 6 Slave devices, the Master device sends an EtherCAT message, the Slave device1 determines whether to process the segment of the EtherCAT sub-message according to an address segment in the EtherCAT sub-message, and forwards the EtherCAT message to the Slave device2 after determining that the segment of the EtherCAT sub-message is not processed or is processed completely, the Slave device2, the Slave device3, the Slave device 4, the Slave device 5, and the Slave device 6 perform similar operations, and the Slave device forwards the EtherCAT message to the Master device after determining that the segment of the EtherCAT sub-message is not processed or is processed completely, where processing the Slave message includes reading a data segment therein and inserting data into the Slave message. As can be seen, although the physical topology is tree-shaped, the data packet needs to be forwarded between the Slave devices and looped back within the Slave, so as to finally form a linear forwarding path.

In addition to the EtherCAT protocol, the Profinet protocol is also a widely used industrial ethernet protocol. The Profinet message is encapsulated by a common Ethernet message, and the message sent to each device is independently sent. The Profinet protocol supports various topologies, when a Controller (Controller) and an industrial terminal (Device) are in a linear topology as shown in fig. 7, the isochronous real-time (IRT) time windows of the Controller and the industrial terminal are aligned, and the IRT message sent by the Controller to each industrial terminal is sent to each industrial terminal within the IRT time window. Considering that the time delay between each industrial terminal and the Controller is different due to the difference of distance and hop count in the linear topology, the Controller will send the message of the far-end terminal (e.g. Device3) first and then the message of the near-end terminal (e.g. Device1) in the period. The Device3 replies to the Controller with a response after receiving the message, the Device2 replies to the Controller with a response after receiving the message, and the Device1 replies to the Device3 with a response after receiving the message.

The existing 5G network supports ethernet sessions, ethernet communication between the terminal device and the data network DN, and ethernet session binding between the DN side interface on the user plane function UPF and the terminal device. As shown in fig. 8, an interface (which may be a physical interface or a logical interface) of the switch device (switch) on the DN side is bound to an ethernet session of the terminal device through a UPF in a 5G network core (5G core, 5GC), and then a message on the ethernet session of the terminal device may be directly forwarded through the bound N6 interface. Wherein the ethernet session may be a PDU session.

In the related art, for a line topology supporting the ethernet protocol, the terminal device mostly accesses the wireless network in the line topology. A possible linear topology structure is shown in fig. 9, a wireless module is installed on a first Slave device (i.e., a Slave terminal 1) on a production line, so that each Slave device on the production line interacts with a Master device through a 5GC, and an industrial terminal on the production line is adapted to a wireless connection. In the online topology, if the network quality between the first node (i.e., the first Slave device) and the wireless network in the production line is unstable, links between other industrial terminals (e.g., the Slave terminal 2 and the Slave terminal 3) of the whole production line and the wireless network all fail, normal communication with the Master device cannot be performed, and the reliability of visible communication cannot be guaranteed.

The terminal equipment can also access the wireless network by adopting a star topology or a tree topology supporting the Ethernet protocol. One possible tree topology may be as shown in fig. 10, where a wireless module is installed on each Slave device on the production line, and each Salve device interacts with a Master device through a 5GC to adapt an industrial terminal on the production line to a wireless connection. If each node on the production line is provided with a wireless module, the cost of the industrial terminal is increased greatly. In addition, for the industrial protocols such as EtherCAT and the like which are combined and sent, the data path is circuitous due to the mode, so that the time delay is not controllable, and the reliability of communication cannot be guaranteed. In a star topology or a tree topology, if the forwarding rule is not changed, the Master only sends one message, and then forwards the message in each terminal device according to the forwarding rule of the line topology, and if the network quality between the first terminal device receiving the message and the wireless network is unstable, links between other terminal devices and the wireless network will also fail, and the reliability of communication cannot be guaranteed. If the forwarding rule is changed, the network device is required to unpack the message sent by the Master and then forward the unpacked message to each terminal device, which may waste the processing resources of the network device, and the network device does not necessarily have the function of unpacking the message, thereby providing a higher requirement for the wireless network and increasing the difficulty of network deployment. And if a reliability guarantee mechanism of high-reliable and low-latency communications (URLLC) defined by 3GPP is adopted, the wireless network needs to support dual-station overlay coverage, and the wireless module of the terminal device also needs to support dual-link capability, which puts high requirements on wireless networking in factory workshops and also increases the cost of the wireless module, so that the difficulty of network deployment and the cost of the terminal are increased in the actual networking of the industrial ethernet protocol.

In summary, when the terminal device, especially the industrial terminal, accesses the wireless network, the reliability of communication cannot be guaranteed, and there may be a waste of processing resources of the network device, a difficulty in network deployment increases, and a cost of the terminal also increases.

Based on this, the embodiment of the present application provides a redundant path creating method, in which a terminal device 10 may receive a message 30 from a user plane function 20 and receive a message 30 from a terminal device 12, and the terminal device 10 may perform deduplication on the message 30 from the user plane function 20 and the message 30 from the terminal device 12, and then send the deduplicated message 30 to a terminal device 11 served by the terminal device 10. The redundant path creation method provided by the embodiment of the application is equivalent to the selection of 2 or more than 2 terminal devices in the terminal devices of the industrial network topology, all the terminal devices in the industrial network topology can be communicated through the traditional fixed network transmission, and all the terminal devices can share the wireless connection, so that all the terminal devices can be accessed into a wireless network through the terminal devices with the network access capability. The wireless connection point between the network equipment and the industrial terminal can transparently forward messages communicated by other nodes through the mobile network, so that mutual backup and load sharing of wireless connection are realized. Therefore, the communication reliability can be guaranteed while the terminal cost is saved and the network deployment difficulty is reduced by combining the actual networking model of the industrial Ethernet protocol under the existing communication system architecture.

The terminal device related to the embodiment of the present application may be an industrial terminal, a wireless module, or an independent wireless access terminal device, such as a Customer Premises Equipment (CPE) and the like.

The embodiment of the application is suitable for industrial terminals and/or industrial applications of industrial Ethernet protocols (such as an EtherCAT protocol or a Profinet protocol) to realize interconnection and intercommunication through the access network. It is understood that embodiments of the present application are applicable to other communication protocols and/or other applications than industrial ethernet protocols. In the embodiment of the present application, an industrial terminal in an industrial ethernet network is mainly taken as an example for description.

The redundant path creation method provided by the embodiment of the application can be applied to the communication system shown in fig. 1. Or the redundant path creating method provided in this embodiment of the present application may be applied to the communication system shown in fig. 11, where the communication system shown in fig. 11 further includes a time-sensitive network application function (TSNAF), the function of the UE may be implemented by a device-side TSN converter (DS-TT), and the function of the UPF may be implemented by a network-side TSN converter (NW-TT). Wherein DS-TT can be deployed with UE and NW-TT can be deployed with UPF. The Slave device can access a wireless network through DS-TT, and the Master device can be connected with an NW-TT User plane (User plane/U-plane).

It can be understood that the embodiment of the present application may also be used for interworking between a 5G network and another network, or an independent 5G network system, for example, for interworking between networks with similar requirements for forwarding industrial messages, and it may also not be limited whether there is another network outside the 5G network, which is not limited in the embodiment of the present application. In the embodiment of the present application, communication between the Master device and the Slave device is mainly taken as an example, but specific names of network functions in a network are not limited, and whether the network functions are deployed in a DN is not limited (for example, both the Master device and the Slave device may be located on a UE side).

In the embodiment of the application, the session management function may create a reliable redundant transmission path for a plurality of terminal devices having a reliable backup relationship, and the plurality of terminal devices having the reliable backup relationship may be respectively deployed on a plurality of industrial terminals, or the plurality of terminal devices may be integrated on one industrial terminal, so as to ensure reliable transmission when the terminal devices access through a wireless network. The process of creating a redundant path for a plurality of terminal devices with a reliable backup relationship by the session management function is shown in fig. 12, and the specific process includes:

s1201: the session management function 21 acquires the terminal device 11 served by the terminal device 10.

In S1201, the terminal device 10 may send information of the terminal device 11 to the session management function 21 to inform the session management function 21 that the terminal device 10 serves the terminal device 11, where the terminal device 11 served by the terminal device 10 may also be a terminal device 11 under the terminal device 10. The terminal device 10 may be a UE, and the terminal device 11 may be a Slave terminal. The session management function 21 receives information from the terminal device 11 of the terminal device 10, and thus obtains information of the terminal device 11 served by the terminal device 10. The information of the terminal device 11 may be, for example, the MAC address of the terminal device 11.

Optionally, the terminal device 10 may report the information of the terminal device 11 to the session management function 21 in a registration process, for example, in an attach process or a PDU session creation process of the terminal device 10.

S1202: the session management function 21 obtains the terminal device 14 served by the terminal device 12.

In S1202, the terminal device 12 may send information of the terminal device 14 to the session management function 21 to inform the session management function 21 that the terminal device 12 serves the terminal device 14, where the terminal device 14 served by the terminal device 12 may also be a terminal device 14 subordinate to the terminal device 12. The terminal device 12 may be a UE, and the terminal device 14 may be a Slave terminal. The session management function 21 receives information of the terminal device 14 from the terminal device 12, and thus obtains information of the terminal device 14 served by the terminal device 12. The information of the terminal device 14 may be, for example, the MAC address of the terminal device 14.

The terminal device 11 and the terminal device 14 may be the same terminal device, or may be different terminal devices. If the terminal device 11 and the terminal device 14 are different terminal devices, other industrial terminals may be disposed between the terminal device 11 and the terminal device 14.

Optionally, the terminal device 12 may report the information of the terminal device 14 to the session management function 21 in a registration process, for example, in an attach process or a PDU session creation process of the terminal device 12.

S1203: the session management function 21 determines that there is a correspondence between the terminal device 10 and the terminal device 12.

The terminal device 10 and the terminal device 12 have a corresponding relationship, so that the terminal device 10 and the terminal device 12 have a reliability pairing relationship, that is, the terminal device 10 and the terminal device 12 have a reliability backup relationship, that is, the terminal device 10 and the terminal device 12 trust each other. When one UE of the terminal device 10 and the terminal device 12 fails or a transmission path where one UE is located fails, the other UE may detect and respond in time to ensure reliable transmission. The detection and response to a fault will be described in the following embodiments. It is to be understood that, for convenience of description, in the embodiment of the present application, only the terminal devices having the corresponding relationship include the terminal device 10 and the terminal device 12 as an example, and the same is applied to a scenario in which more than 2 terminal devices have the corresponding relationship.

The session management function 21 may acquire the terminal device 10 and the terminal device 12 accessing the wireless network, and may acquire the terminal device having a corresponding relationship with the terminal device 10 and the terminal device having a corresponding relationship with the terminal device 12. In a possible manner, the session management function 21 may obtain subscription data of the UE, where the subscription data has a Reliability pairing relationship of the UE, for example, Reliability Group (UE1, UE2, and UE3), and this subscription manner indicates that two of the three terminal devices UE1, UE2, and UE3 have a Reliability pairing relationship with each other, and for example, the subscription manner of the Reliability Group (UE1, UE2), the Reliability Group (UE2, UE3) indicates that the UE1 and the UE2 have a Reliability pairing relationship, and the UE2 and the UE3 have a Reliability pairing relationship with each other. In another possible manner, in a UE registration process (e.g., an attach process or a PDU session creation process), the session management function 21 may obtain subscription data of the UE, and the session management function 21 may determine a reliable pairing relationship between the UEs according to the subscription data, for example, the session management function 21 obtains the subscription data of the UE from a subscription database, and obtains the reliable pairing relationship between the UEs from the subscription data. Optionally, the session management function 21 may store subscription data of the UE itself, or optionally, the session management function 21 may obtain the subscription data of the UE from another device (e.g., UDM). Specifically, the session management function 21 obtains subscription data of the terminal device 10, and determines that the terminal device 10 and the terminal device 12 have a corresponding relationship according to the subscription data of the terminal device 10, and the session management function 21 may also obtain subscription data of the terminal device 12, and determines that the terminal device 12 and the terminal device 10 have a corresponding relationship according to the subscription data of the terminal device 12.

The reliable pairing relationship of the UE in the subscription data may be statically signed by the subscription data of the UE, or may be dynamically created by modifying the subscription data. If the reliable pairing relationship of the UE is dynamically created, a third-party network element (e.g., AF) may modify the subscription data of the UE through a network open function NEF or PCF, that is, the third-party network element may add, in the subscription data of the UE, information (e.g., UE identifier, etc.) of the UE that is in the reliable pairing relationship with each other, and indicate that the UE and the added UE are in the reliable pairing relationship with each other.

Optionally, the subscription data of the UE may further include a primary-standby relationship between UEs having a reliable pairing relationship, for example, the terminal device 10 and the terminal device 12 have a corresponding relationship, the terminal device 10 is a primary UE, and the terminal device 12 is a secondary UE. Also, for example, the terminal device 10 and the terminal device 12 are in a master-Slave relationship with each other, when the terminal device 10 serves as a master UE to serve one or more Slave devices, the terminal device 12 is a Slave UE of the terminal device 10, and when the terminal device 12 serves as a master UE to serve one or more other Slave devices, the terminal device 10 is a Slave UE of the terminal device 12.

After the session management function 21 determines that the terminal device 10 and the terminal device 12 have a corresponding relationship, the session management function 21 may further send the information of the terminal device 10 and/or the information of the terminal device 11 to the terminal device 12, and send the information of the terminal device 12 and/or the information of the terminal device 14 to the terminal device 10.

The execution sequence of S1201, S1202 and S1203 is not limited herein.

S1204: the session management function 21 sends a forwarding rule to the user plane function 20, where the forwarding rule indicates that a message is sent to the terminal device 11 through the terminal device 10 and a message is sent to the terminal device 14 through the terminal device 12. The user plane function 20 receives the forwarding rules.

The forwarding rules may instruct the user plane function 20 to send a message (i.e., a downlink message or a downlink data message) from the Master device to the industrial terminal. For example, the forwarding rule may instruct the user plane function 20 to send a message to the terminal device 11 through the terminal device 10 and to send a message to the terminal device 14 through the terminal device 12. The forwarding rule may further instruct the user plane function 20 to send a message to the terminal device 11 through the terminal device 12, and send a message to the terminal device 14 through the terminal device 10.

Optionally, the forwarding rule may further instruct the user plane function 20 to report a response (i.e., an uplink message or an uplink data message or an uplink response message) from the industrial terminal to the Master device. For example, the forwarding rule may instruct the user plane function 20 to receive a response from the terminal device 11 through the terminal device 10 and then report the response to the Master device, and to receive a response from the terminal device 14 through the terminal device 12 and then report the response to the Master device. The forwarding rule may further instruct the user plane function 20 to receive a response from the terminal device 11 through the terminal device 12, and then report the response to the Master device, and to receive a response from the terminal device 14 through the terminal device 10, and then report the response to the Master device.

In a possible manner, the session management function 21 may further make different forwarding rules for the user plane function 20 according to whether the Slave device supports redundant transmission. If the Slave equipment supports a redundant path, the Slave equipment may duplicate a packet, and if the Slave equipment does not support redundant transmission, the Slave equipment may not have the capability of copying or deduplicating the packet.

When the Slave device supports redundant transmission, the Master device may or may not support redundant transmission. When the Slave device does not support redundant transmission, the Master device may or may not support redundant transmission. The Master may copy or duplicate the packet if the Master device supports redundant transmission, and the Master may not have the capability of copying or duplicate the packet if the Master device does not support redundant transmission.

For example, the Slave device supports redundant transmission and the Master device supports redundant transmission. In the downlink message transmission process, the Master may copy a message, and send the message and the copied message to the user plane function 20, and the forwarding rule may instruct the user plane function 20 to send the message to the terminal device 11 through the terminal device 10 and send the copied message to the terminal device 11 through the terminal device 12. Optionally, the terminal device 11 may process the two messages. Or because the Slave device can duplicate the messages, the terminal device 11 duplicates the two messages, and then processes the messages obtained through duplication deletion. In the uplink message transmission process, the Slave device may copy a response, send the response to the user plane function 20 through the terminal device 10, send the copied response to the user plane function 20 through the terminal device 12, and the forwarding rule may instruct the user plane function 20 to report the received response to the Master device. Optionally, the Master device may process two responses. Or the Master device can remove the duplicate responses, and then the Master device can remove the duplicate responses and process the responses obtained by removing the duplicate responses.

And as another example, the Slave device supports redundant transmission and the Master device does not support redundant transmission. In the downlink message transmission process, the Master device does not have the capability of copying the message, and sends the message to the user plane function 20, and the forwarding rule may instruct the user plane function 20 to copy the message, send the message to the terminal device 11 through the terminal device 10, and send the copied message to the terminal device 11 through the terminal device 12. Optionally, the terminal device 11 may process the two messages. Or because the Slave device can duplicate the messages, the terminal device 11 duplicates the two messages, and then processes the messages obtained through duplication deletion. In the uplink message transmission process, the Slave device may copy the response, and send the response to the user plane function 20 through the terminal device 10. Since the Master device does not have the capability of removing duplicate packets, the forwarding rule may instruct the user plane function 20 to remove duplicate responses, and report the responses obtained by the duplicate removal to the Master device. And the Master equipment processes the received response obtained by the de-duplication.

And as another example, the Slave device does not support redundant transmission and the Master device supports redundant transmission. In the downlink message transmission process, the Master may copy a message, and send the message and the copied message to the user plane function 20, and the forwarding rule may instruct the user plane function 20 to send the message to the terminal device 11 through the terminal device 10 and send the copied message to the terminal device 11 through the terminal device 12. Optionally, the terminal device 11 may process the two messages. Or because the Slave device does not have the capability of removing duplicate packets, the terminal device 10 serving the terminal device 11 may remove duplicate packets, and the terminal device 11 processes the messages obtained by removing duplicate packets. In the process of uplink message transmission, the Slave device does not have the capability of copying response. Optionally, the terminal device 11 may send a response to the user plane function 20 through the terminal device 10 or the terminal device 12, and the forwarding rule may instruct the user plane function 20 to copy the response and report the response and the copied response to the Master device. Or alternatively, the terminal device 10 serving the terminal device 11 may copy the response, and send the response and the copied response to the user plane function 20, where the forwarding rule may indicate that the response and the copied response are reported to the Master device. Optionally, the Master device may process two responses. Or optionally, since the Master device may perform deduplication, the Master device may perform deduplication on two responses, and then process a response obtained by deduplication.

And as another example, the Slave device does not support redundant transmission and the Master device does not support redundant transmission. In the downlink message transmission process, the Master device does not have the capability of copying the message, and sends the message to the user plane function 20, and the forwarding rule may instruct the user plane function 20 to copy the message, send the message to the terminal device 11 through the terminal device 10, and send the copied message to the terminal device 11 through the terminal device 12. Optionally, the terminal device 11 may process the two messages. Or because the Slave device does not have the capability of removing duplicate packets, the terminal device 10 serving the terminal device 11 may remove duplicate packets, and the terminal device 11 processes the messages obtained by removing duplicate packets. In the process of uplink message transmission, the Slave device does not have the capability of copying response. Optionally, the terminal device 10 serving the terminal device 11 may copy the response, and send the response and the copied response to the user plane function 20, where the forwarding rule may instruct the user plane function 20 to perform deduplication response, and report the response obtained by deduplication to the Master device. And the Master equipment processes the received response obtained by the de-duplication.

S1205: the session management function 21 establishes and sends an uplink and downlink packet forwarding rule to the terminal device 10 for the terminal device 10, and establishes and sends an uplink and downlink packet forwarding rule to the terminal device 12 for the terminal device 12. The terminal device 10 and the terminal device 12 receive the uplink and downlink packet forwarding rules, respectively.

The process of S1205 may be regarded as that the session management function 21 creates a reliability redundant transmission path for the UE with reliability pairing relationship. That is, the session management function 21 establishes a routing map of data packets for the UE with reliable pairing relationship. In S1205, the session management function 21 may make a forwarding rule for UE differentiation according to whether the Slave device served by the UE supports redundant transmission. For the main UE and the standby UE, the context packet forwarding rule established by the network device for the main UE and the uplink and downlink packet forwarding rules established for the standby UE may be the same or different.

In one embodiment, the Slave devices (e.g., terminal devices 11 and/or 14) support redundant transmissions. In this scenario, the Slave device may copy and deduplicate the upper and lower packets. The Master device may or may not support redundant transmission.

For example, the terminal device 10 is a Master UE, the terminal device 12 is a slave UE, and the Master device sends a message to the terminal device 11. The downlink packet forwarding rule established by the session management function 21 for the terminal device 10 may be: if the terminal device 10 receives the message sent to the terminal device 11, the terminal device 10 sends the message to the terminal device 11. The downlink packet forwarding rule established for the terminal device 12 may be: if the terminal device 12 receives the message sent to the terminal device 11, the terminal device 14 sends the message to the terminal device 11. That is, the Master device may send a downlink packet to the Slave device served by the Master UE through the Master UE and the Slave UE. Here, it can be considered that the downlink messaging rules established by the master UE and the standby UE are the same.

Because the master UE and the standby UE send the same downlink packet to the Slave device served by the master UE, the Slave device may perform deduplication on the received downlink packet.

For example, the terminal device 10 is a Master UE, the terminal device 12 is a slave UE, and the terminal device 11 sends a response (i.e., an uplink packet) to the Master device. The uplink packet forwarding rule established for the terminal device 10 may be: if the terminal device 10 receives the response sent by the terminal device 11, the terminal device 10 sends the response to the Master device. The uplink packet forwarding rule established for the terminal device 12 may be: if the terminal device 12 receives the response sent by the terminal device 11, the terminal device 12 sends the response to the Master device. That is, the Master device may receive, through the Master UE and the standby UE, an uplink packet from a Slave device served by the Master UE. Here, it can be considered that the forwarding rules of the downlink data packets established by the master UE and the standby UE are the same.

The Slave device may copy the uplink packet and then send the same uplink packet to the master UE and the standby UE.

In another embodiment, the Slave devices (e.g., terminal device 11 and/or terminal device 14) do not support redundant transmission. In this scenario, the UPF and/or the UE may perform duplication and deduplication of the context. The Master device may or may not support redundant transmission.

For example, the terminal device 10 is a Master UE, the terminal device 12 is a slave UE, and the Master device sends a message to the terminal device 11. The downlink packet forwarding rule established by the Master device for the terminal device 12 may be: if terminal device 12 receives the message sent to terminal device 11, terminal device 12 sends the message to terminal device 10. The downlink packet forwarding rule established for the terminal device 10 may be: the terminal device 10 performs deduplication on the message sent by the user plane function 20 and the message sent by the terminal device 12, and then sends the deduplicated message to the terminal device 11. That is, the Master device may send a downlink packet to the Slave device served by the Master UE through the Master UE and the Slave UE. Here, the downlink message forwarding rules established for the main UE and the standby UE are different.

For example, the terminal device 10 is a Master UE, the terminal device 12 is a slave UE, and the terminal device 11 sends a response (i.e., an uplink packet) to the Master device. The uplink packet forwarding rule established for the terminal device 10 may be: if the terminal device 10 receives the response sent by the terminal device 11, the terminal device 10 sends the response to the user plane function 20, and optionally, the terminal device 10 copies the response and sends the copied response to the terminal device 12. The uplink packet forwarding rule established for the terminal device 12 may be: if the terminal device 12 receives the response sent by the terminal device 11, the terminal device 12 sends the response to the user plane function 20. That is, the Master device may receive, through the Master UE and the optional standby UE, a data packet of a Slave device served by the Master UE. Here, the uplink message forwarding rules established for the main UE and the standby UE are different.

Optionally, the session management function 21 may send first information to the terminal device 10, where the first information indicates that the terminal device 10 sends the terminal device 11 after the duplicate removal of the packet from the user plane function 20 and the packet from the terminal device 12, that is, the terminal device 10 sends the terminal device 11 after the duplicate removal of the packet from the user plane function 20 and the packet from the terminal device 12 according to the first information. Wherein the session management function 21 may instruct the terminal device 10 to send the message from the user plane function 20 and the message from the terminal device 12 to the terminal device 11 after de-duplication by one or more cells. In the case of indication by a plurality of information elements, the plurality of information elements may be referred to as the first information.

The network device may establish a direct link (e.g., SideLink) between UEs having a reliable pairing relationship. The network device may determine whether to establish a direct link between UEs according to a network topology between UEs having a reliable pairing relationship. Taking the UE with the reliable pairing relationship as the primary and secondary UEs as an example, if there is an available network topology connection between the primary and secondary UEs, the network device may not establish a direct link between the primary and secondary UEs, and if there is no available network topology connection between the primary and secondary UEs, the network device may establish a direct link between the primary and secondary UEs. The session management function 21 may determine that available network topology connection exists between the active and standby UEs when it is determined that the Slave device supports redundant transmission, and determine that available network topology connection does not exist between the active and standby UEs when it is determined that the Slave device does not support redundant transmission. When the Slave device supports redundant transmission, a communication port of the Slave device may support bidirectional transmission, for example, support main UE- > Slave device- > standby UE, and support standby UE- > Slave device- > main UE, and at this time, if the Slave device is connected between the main UE and the standby UE, it may be regarded that there is available network topology connection between the main UE and the standby UE. Otherwise, when the Slave device does not support redundant transmission, a communication port of the Slave device does not support bidirectional transmission, for example, only supports primary UE- > Slave device- > standby UE, or only supports standby UE- > Slave device- > primary UE, and at this time, if the Slave device is connected between the primary and standby UEs, it may be regarded that there is no available network topology connection between the primary and standby UEs. Optionally, the session management function 21 sends second information to the terminal device 10, where the second information indicates that the terminal device 10 establishes a transmission path with the terminal device 12. The session management function 21 sends third information to the terminal device 12, where the third information indicates that the terminal device 12 establishes a transmission path with the terminal device 10.

In the embodiment of the application, the session management function creates reliable redundant transmission paths for a plurality of terminal devices with reliable pairing relationships, so that reliable transmission can be guaranteed when the terminal devices are accessed through a wireless network.

The embodiment shown in fig. 12 is described below with reference to a serial industrial terminal access 5G network supporting the EtherCAT protocol as a specific embodiment. The industrial terminal D is accessed to a wireless network through an integrated wireless module or an external wireless device (such as CPE), and service interaction is carried out between the industrial terminal D and the Master device through the wireless network. In general, as shown in (a) in fig. 13, the transmission path is Master- > UE1- > D1- > D2- > D3- > D4- > D3- > D2- > D1- > UE1- > Master. As shown in fig. 13 (b), a communication model of the embodiment of the application is that a UE1 and a UE2 have a reliability pairing relationship, a loop redundancy transmission mechanism is formed inside a 5G network, the UE1 and the UE2 can access the same or different access network devices, and the UE1 and the UE2 can access the same or different user plane functions, which is not limited herein, so that transmission reliability of the 5G network is guaranteed.

The creation of redundant paths by the session management function SMF is explained based on the communication model shown in fig. 13 (b), and with reference to fig. 14, the method includes the following steps:

s1401: the UDM stores subscription data of the UE1 (the terminal device 10) and the UE2 (the terminal device 12), the subscription data of the UE1 includes information on the UE having the reliability pairing relationship with the UE1, and the subscription data of the UE2 includes information on the UE having the reliability pairing relationship with the UE 2.

For example, the UE1 and the UE2 have a reliable pairing relationship, and the subscription data of the UE1 includes information of the UE2, and the subscription data of the UE2 includes information of the UE 1. Optionally, the reliability pairing relationship may also indicate a primary-backup relationship of the UE, for example, the UE1 is a primary UE, and the UE2 is a backup UE.

S1402: the UE1 sends a session creation request to the SMF, where the session creation request carries information of a Slave device (e.g., terminal device 11) under the control of the UE1 or serving the Slave device. For example, the session creation request carries the MAC address of the Slave device served by the UE 1.

S1403: the UE2 sends a session creation request to the SMF, where the session creation request carries information of a Slave device (e.g., the terminal device 14) under the control of the UE2 or serving the Slave device. For example, the session creation request carries the MAC address of the Slave device served by the UE 2.

S1404: the SMF acquires the subscription data of the UE1 and the subscription data of the UE2 from the UDM, and the SMF determines that the UE1 and the UE2 have a reliability pairing relation according to the subscription data of the UE1 and the subscription data of the UE 2.

Optionally, the SMF determines that the UE1 is the master UE and the UE2 is the slave UE according to the subscription data of the UE1 and the subscription data of the UE 2.

S1405: the SMF establishes or modifies forwarding rules for UE1 and UE2 on the user plane function UPF.

For example, the SMF creates or modifies uplink and downlink message forwarding rules (e.g., PDU session context or PDR, etc.) on the UPF about UE1 and UE2 through N4 session creation or modification messages, respectively. For example, the SMF may send the downlink ingress port id and the uplink egress port id corresponding to the PDU sessions of the UE1 and the UE2 to the UPF through the N4 session creation or modification message. Wherein, the downstream ingress port identification and the upstream egress port identification can be represented by port numbers or VLAN tags.

In the up-and-down message forwarding rule of the UE1, it is recorded that the UE2 is a UE having a reliable pairing relationship with the UE1, and optionally, it is recorded that the UE2 is a standby UE of the UE 1. In the up-and-down message forwarding rule of the UE2, it is recorded that the UE1 is a UE having a reliable pairing relationship with the UE2, and optionally, the UE1 is a main UE of the UE 2.

In one possible scenario, the Slave device supports redundant paths.

As shown in fig. 15 (a), the rules are downlink packet forwarding rules of the UE1 and the UE2 stored in the UPF. The UPF receives the downlink message through the N6 port, matches the PDU session of the UE1 and/or the UE2 which transmits the downlink message according to the PDR and the port identification of the downlink message (the source MAC address S-MAC and/or the destination MAC address D-MAC can also be combined), and sends the PDU session to the UE1 and/or the UE2 through the N3 port based on the FAR 1. At this time, the downlink port corresponding to the PDU session of UE1 and UE2 is identified as N3.

As shown in fig. 15 (b), the uplink packet forwarding rules for the UE1 and the UE2 are stored in the UPF. The UPF receives the uplink message through the N3 port, determines the uplink egress port identifier of the uplink message according to the PDR and the port identifier of the uplink message, sends the uplink message from the UE1 to the SMF through the N6 port, and sends the uplink message from the UE2 to the SMF through the N6 port. The port identifier of the uplink packet may be an N3 tag, such as a tunnel end point identifier (TEID).

In another possible scenario, the Slave device does not support redundant transmission.

As shown in fig. 16 (a), the downlink packet forwarding rules are the downlink packet forwarding rules of UE1 and UE2 stored in the UPF. In the uplink and downlink packet forwarding rule of the UE1 in the UPF, the SMF instructs the UPF to copy the downlink packet received through the N6 port, and sends the downlink packet to the UE1 and the UE 2.

As shown in fig. 16 (b), the uplink forwarding rules for UE1 and UE2 are stored in the UPF. In the uplink packet forwarding rule of the UE1 in the UPF, the SMF instructs the UPF to perform deduplication on an uplink packet from the UE1 and an uplink packet from the UE2 received through the N3 port, and sends the deduplicated uplink packet to the SMF through the N6 port. In the forwarding rule of the UE2 in the UPF, the SMF instructs the UPF to forward the uplink packet received through the N3 port to the UE 1. The SMF includes address information of the Slave device served by the UE1 or a multicast/broadcast/special address in the forwarding rule of the UE2 as a packet filtering condition in the forwarding rule of the UE 2.

S1406: the SMF sends a session creation response message to the UE1, the session creation response message including the address of the UE2 and/or the addresses of Slave devices subordinate or served by the UE 2. Optionally, the session creation response message indicates that the UE1 is the master UE and/or indicates that the UE2 is the standby UE.

S1407: the SMF sends a session creation response message to the UE2, the session creation response message including the address of the UE1 and/or the addresses of Slave devices subordinate or served by the UE 1. Optionally, the session creation response message indicates that the UE1 is the master UE and/or indicates that the UE2 is the standby UE.

S1408: the UE1 and the UE2 create internal data forwarding rules from the session creation response message received from the SMF.

In one possible scenario, the Slave device supports redundant transmission, as shown in fig. 17.

In the downlink packet forwarding rule of the UE2, if the UE2 receives a downlink packet sent to a Slave device served by the UE1, the UE2 sends the downlink packet to the Slave device served by the UE 1. The UE2 may determine that the downlink packet is a data packet sent by the SMF to the Slave device served by the UE1 according to the address of the UE1 and/or the address of the Slave device subordinate to or served by the UE1, which are included in the session creation response message in S1406.

In the downlink packet forwarding rule of the UE1, if the UE1 receives a downlink packet sent to a Slave device served by the UE1, the UE1 sends the downlink packet to the Slave device served by the UE 1.

In the forwarding rule of the uplink packet of the UE2, if the UE2 receives the uplink packet sent by the Slave device served by the UE1, the UE2 sends the uplink packet to network devices such as a base station/UPF/SMF.

In the uplink packet forwarding rule of the UE1, if the UE1 receives an uplink packet sent by a Slave device served by the UE1, the UE1 sends the uplink packet to a base station/UPF/SMF or other network devices.

In another possible scenario, the Slave device does not support redundant paths, as shown in fig. 18.

In the downlink packet forwarding rule of the UE2, if the UE2 sends a downlink packet to a Slave device served by the UE1, the UE2 sends the downlink packet to the UE 1.

In the downlink packet forwarding rule of the UE1, if the UE1 receives the downlink packet from the UPF and the downlink packet from the UE2, the downlink packet from the UPF and the downlink packet from the UE2 are deduplicated, and the deduplicated downlink packet is sent to the Slave device served by the UE 1.

In the uplink packet forwarding rule of the UE2, if the UE2 receives an uplink packet sent by the UE1, the UE2 sends the uplink packet to network devices such as a base station/UPF/SMF.

In the uplink message forwarding rule of the UE1, if the UE1 receives an uplink message sent by a Slave device served by the UE1, the UE1 sends the uplink message to a network device, and in addition, the UE1 copies the uplink message and sends the copied uplink message to the UE 2.

In the embodiment of the application, under the actual networking scene that the industrial terminal supporting the EtherCAT protocol communicates through the 5G network, the reliable transmission can be ensured when the industrial terminal is accessed through a wireless network, and the reliability of the wireless network is improved.

On the basis of the embodiment for creating the redundant path, when the node on the data transmission link does not fail, the embodiment of the application also provides a reliable transmission process based on the redundant path.

In one possible scenario, the Slave device supports redundant transmission, and as described in conjunction with fig. 17, the UE1 is the terminal device 10, the UE2 is the terminal device 12, the D1 is the terminal device 11, and the D4 is the terminal device 14.

The Master device sends a message 30 to the user plane function 20, and the user plane function 20 sends the message 30 to the terminal device 10 and the terminal device 12. The terminal device 10 sends the message 30 to the terminal device 11, and the terminal device 11 receives the message 30 from the terminal device 10. The terminal device 12 sends the message 30 to the terminal device 14, the terminal device 14 sends the message 30 to the terminal device 11 through D3 and D2, and the terminal device 11 receives the message 30 from the terminal device 12.

In a possible manner, the terminal device 11 sends a response 33 to the terminal device 10 for the message 30 from the terminal device 10. The terminal device 10 sends the response 33 to the user plane function 20, and the user plane function 20 sends the response 33 to the Master device. The terminal device 11 sends a response 34 to the terminal device 12 through the D2, the D3 and the terminal device 14 for the message 30 from the terminal device 12. The terminal device 12 sends the response 34 to the Master device.

In another possible manner, the terminal device 11 may perform deduplication on the packet 30 from the terminal device 10 and the packet 30 from the terminal device 12. The terminal device 11 sends a response 38 to the terminal device 10 for the deduplicated packet 30. The terminal device 10 sends the response 38 to the user plane function 20, and the user plane function 20 sends the response 28 to the Master device. Optionally, the terminal device 11 may further copy the response 38 to obtain a response 39. The terminal device 11 sends the response 39 to the terminal device 12 through the terminal devices 14, D2, D3. The terminal device 12 sends the response 39 to the Master device.

The response 39 is duplicated from the response 38, and the data included in the response 30 and the data included in the response 38 may be completely identical or may be partially identical.

In another possible scenario, the Slave device does not support redundant transmission, and as described in conjunction with fig. 18, the UE1 is the terminal device 10, the UE2 is the terminal device 12, the D1 is the terminal device 11, the D4 is the terminal device 14, and a transmission path is established between the terminal device 10 and the terminal device 12.

The Master device sends a message 30 to the user plane function 20, and the user plane function 20 sends the message 30 to the terminal device 10 and the terminal device 12. The terminal device 10 receives a message 30 from the user plane function 20. The terminal device 12 sends the message 30 to the terminal device 10, and the terminal device 10 receives the message 30 from the terminal device 12. The terminal device 10 de-duplicates the message 30 from the user plane function 20 and the message 30 from the terminal device 12. And the terminal device 10 sends the duplicate-removed message to the terminal device 11.

The terminal device 11 receives the deduplicated packet 30 from the terminal device 10, and sends a response 36 to the terminal device 10 for the deduplicated packet 30 from the terminal device 10. The terminal device 10 sends the response 36 to the user plane function 20, and the user plane function 20 sends the response 36 to the Master device.

The terminal device 11 receives the message 30 from the terminal device 12 through the terminal device 10, and sends a response 37 to the terminal device 10 for the message 30 from the terminal device 12. The terminal device 10 sends the response 37 to the terminal device 12, the terminal device 12 sends the response 37 to the user plane function 20, and the user plane function 20 sends the response 37 to the Master device.

On the basis of the embodiment for creating the redundant path, when a node on a data transmission link fails, the embodiment of the application also provides a reliable transmission process based on the created redundant path, so that the reliability protection of data transmission can be realized. The possible failure of the data transmission link is shown in fig. 19, and the failure may occur: (1) mobile network access part, e.g. between UE and UPF, (2) UE (e.g. industrial CPE, etc.), (3) Slave device. The reliability transmission process for the occurrence of the fault in the embodiment of the present application may be applied to the architecture shown in fig. 17, and may also be applied to the architecture shown in fig. 18.

(1) The mobile network access part fails, such as between the UE and the network device. Assuming that a failure occurs between the UE1 and the UPF, the Master device sends a downlink message to the UE2 (e.g., the terminal device 12), and the UE2 sends a received downlink message to the UE1, so that even if the mobile network access portion on the UE1 side fails, the UE1 may also receive the downlink message sent by the Master device from the mobile network access link on the UE2 side. For the uplink message sent by the Slave device D1 to the Master device, the UE1 sends the received uplink message to the UE2, and the UE2 sends the uplink message to the Master device through the mobile network.

Alternatively, the UE2 may be notified of a state that mobile network access is unavailable from the UE1 side. For example, the UE1, a control plane network element, or a user plane network element notifies the UE2 that mobile network access is unavailable on the UE1 side.

When the UE2 determines that the mobile network access on the UE1 side is unavailable, the UE2 may send the downlink message directly to the Slave device. The Slave device may send the uplink message directly to the UE 2.

In a scenario that the Slave device supports redundant transmission:

the transmission process of the downlink message may include: master- > UPF- > AN- > UE2- > D4- > D3- > D2- > D1, or Master- > UPF- > AN- > UE2- > D4- > D3- > D2- > D1- > UE1- > D1. That is, the terminal device 11 (i.e., D1) can receive the message 35 from the terminal device 12 (i.e., UE2) through the industrial terminal D.

The transmission process of the uplink message may include: d1- > D2- > D3- > D4- > UE2- > AN- > UPF- > Master, or D1- > UE1- > D1- > D2- > D3- > D4- > UE2- > AN- > UPF- > Master.

In a scenario where the Slave device does not support redundant transmission:

the transmission process of the downlink message may include: master- > UPF- > AN- > UE2- > UE1- > D1. That is, the terminal device 10 (i.e., the UE1) may receive the message 35 from the terminal device 12 (i.e., the UE2) and send the message 35 to the terminal device 11 (i.e., the D1). That is, terminal device 11 (i.e., D1) may receive message 35 from terminal device 12 (i.e., UE 2).

The transmission process of the uplink message may include: d1- > UE1- > UE2- > AN- > UPF- > Master.

(2) The UE fails. Assuming that the UE1 fails, there may be a failure detection mechanism between the UE1 and the UE2, and also between the UE1 and the D1. When the UE1 fails, the UE2 and/or the D1 may quickly detect that the UE1 fails, and the D1 may interrupt the link between the D1 and the UE1, and connect the port where the D1 and the UE1 are connected to form a loop. After the UE2 receives the downlink message sent by the Master, the UE2 sends the downlink message to the Slave device, and since the D1 forms a loop with the port where the D1 is connected to the UE1, the D1 sends the uplink message to the Master device through the UE 2.

In a scenario where the Slave device supports/does not support redundant transmission:

the transmission process of the downlink message may include: master- > UPF- > AN- > UE2- > D4- > D3- > D2- > D1. That is, the terminal device 11 (i.e., D1) can receive the message 35 from the terminal device 12 (i.e., UE2) through the industrial terminal D.

The transmission process of the uplink message may include: d1- > D2- > D3- > D4- > UE2- > AN- > UPF- > Master.

(3) The Slave device fails. Assuming that D2 fails, D1 and D3 may detect that D2 fails through a failure detection mechanism, and when a link between D1 and D2 fails, D1 and D3 generate failure detection messages respectively, and the failure detection messages carry a failure point D2, and send the failure detection messages to Master equipment. The UE1 may receive the failure detection packet from the D1, analyze the failure detection packet, determine that the failure point is D2, and the UE1 sends the failure detection packet to the Master device. The UE2 may receive the failure detection packet from the D3, analyze the failure detection packet, determine that the failure point is D2, and the UE2 sends the failure detection packet to the Master device. After receiving the fault detection messages from the UE1 and the UE2, the Master device constructs a downlink message sent to the Slave device into two messages, and sends the two messages to the D1, the D3 and the D4, respectively. Master equipment sends downlink messages to D1 through UE1, and sends downlink messages to D3 and D4 through UE 2. After the UE1 and the UE2 receive the downlink message from the Master device, since it is determined that the failure point is D2, the UE1 sends the downlink message to D1, and the UE2 sends the downlink message to D3 and D4.

In a scenario that the Slave device supports redundant transmission:

the transmission process of the downlink message may include: master- > UPF- > AN- > UE1- > D1 and Master- > UPF- > AN- > UE2- > D4- > D3.

The transmission process of the uplink message may include: d1- > UE1- > AN- > UPF- > Master and D3- > D4- > UE2- > AN- > UPF- > Master.

In a scenario where the Slave device does not support redundant transmission:

the transmission process of the downlink message may include: master- > UPF- > AN- > UE1- > D1 or Master- > UPF- > AN- > UE2- > UE1- > D1; or Master- > UPF- > AN- > UE2- > D4- > D3, or Master- > UPF- > AN- > UE1- > UE2- > D4- > D3.

The transmission process of the uplink message may include: d1- > UE1- > AN- > UPF- > Master or D1- > UE1- > UE2- > AN- > UPF- > Master; or D3- > D4- > UE2- > UE1- > AN- > UPF- > Master.

In the embodiment of the present application, only two UEs (UE1 and UE2) and 4 Slave devices (D1, D2, D3, and D4) are taken as an example for explanation, and the number of UEs and the number of Slave devices are not limited in an actual communication scenario. In the embodiment of the application, in the scene that the industrial terminal supporting the EtherCAT protocol is accessed through the 5G network, the rapid detection and positioning of the fault are realized, and different redundancy transmission strategies can be implemented according to different fault points, so that the high reliability of the service is ensured.

The redundant path creating method according to the embodiment of the present application is described in detail above with reference to fig. 12 to fig. 19, and based on the same inventive concept as the redundant path creating method, the embodiment of the present application further provides a communication apparatus, as shown in fig. 20, where the communication apparatus 2000 includes a processing unit 2001 and a transceiver unit 2002, and the apparatus 2000 can be used to implement the method described in the method embodiment applied to the network device or the network device.

In one embodiment, apparatus 2000 is applied to a terminal device, where the terminal device may be terminal device 10.

Specifically, the transceiver 2002 is configured to receive a message 30 from the user plane function 20, and the communication device serves the terminal device 11; receiving the message 30 from the terminal device 12;

the processing unit 2001 is configured to duplicate the packet 30 from the user plane function 20 and the packet 30 from the terminal device 12;

the transceiver 2002 is further configured to send the deduplicated message 30 to the terminal device 11.

In one implementation, the transceiver 2002 is further configured to receive a response 31 from the terminal device 11, where the response 31 corresponds to the deduplicated packet 30; sending a response 32 to the terminal device 12, the response 32 corresponding to the message 30 from the terminal device 12.

In one implementation, the transceiver 2002 is further configured to receive a message 35 from the terminal device 12 and send the message 35 to the terminal device 11 if a fault occurs between the communication apparatus and the user plane function 20.

In an implementation manner, the transceiver 2002 is further configured to receive first information from a session management function 21, where the first information indicates that a message from the user plane function 20 and a message from the terminal device 12 are deduplicated and then sent to the terminal device 11.

In one implementation, the transceiver 2002 is further configured to receive second information from the session management function 21, where the second information indicates that a transmission path between the terminal device 12 and the terminal device is established.

In another embodiment, the apparatus 2000 is applied to a network device, wherein the network device is the session management function 21.

Specifically, the transceiver 2002 is configured to obtain a terminal device 11 served by the terminal device 10; a terminal device 14 that obtains services of the terminal device 12;

the processing unit 2001 is configured to determine that the terminal device 10 and the terminal device 12 have a correspondence relationship;

the transceiver 2002 is further configured to send a forwarding rule to the user plane function 20, where the forwarding rule indicates that a message is sent to the terminal device 11 through the terminal device 10 and a message is sent to the terminal device 14 through the terminal device 12.

In one implementation, the forwarding rule further indicates that the packet is copied.

In one implementation, the transceiver 2002 is further configured to send, to the terminal device 10, first information indicating that a message from the user plane function 20 and a message from the terminal device 12 are to be deduplicated and then sent to the terminal device 11.

In one implementation, the transceiver 2002 is further configured to send second information to the terminal device 10, where the second information indicates establishment of a transmission path with the terminal device 12.

The transceiver is further configured to send third information to the terminal device 12, where the third information indicates establishment of a transmission path with the terminal device 10.

In one implementation, the transceiver 2002 is specifically configured to receive information from the terminal device 11 of the terminal devices 10.

In one implementation, the transceiver 2002 is specifically configured to receive information of the terminal device 14 from the terminal devices 12.

In one implementation, the processing unit 2001 is specifically configured to obtain subscription data of the terminal device 10, where the subscription data of the terminal device 10 indicates that there is a corresponding relationship with the terminal device 12; and/or obtaining subscription data of the terminal device 12, where the subscription data of the terminal device 12 indicates that there is a corresponding relationship with the terminal device 10.

In yet another embodiment, the apparatus 2000 is applied to a terminal device, wherein the terminal device may be the terminal device 11.

Specifically, the transceiver 2002 is configured to receive a message 30 from the terminal device 10; receiving the message 30 from the terminal device 12;

the processing unit 2001 is configured to determine the message 30;

the transceiver 2002 is further configured to send a response 33 to the terminal device 10, where the response 33 corresponds to the message 30 from the terminal device 10; sending a response 34 to the terminal device 12, the response 34 corresponding to the message 30 from the terminal device 12.

In one implementation, the transceiver 2002 is further configured to receive a message 35 from the terminal device 12 if a fault occurs between the terminal device 10 and the user plane function 20 or if the terminal device 10 fails.

Specifically, the transceiver 2002 is configured to receive a message 30 from the terminal device 10; receiving the message 30 from the terminal device 12 through the terminal device 10;

the processing unit 2001 is configured to determine the message 30;

the transceiver 2002 is further configured to send a response 36 to the terminal device 10, where the response 36 corresponds to the message 30 from the terminal device 10; sending a response 37 to the terminal device 12 via the terminal device 10, the response 37 corresponding to the message 30 from the terminal device 12.

It should be noted that, the division of the modules in the embodiments of the present application is schematic, and is only a logical function division, and in actual implementation, there may be another division manner, and in addition, each functional unit in each embodiment of the present application may be integrated in one processing unit, or may exist alone physically, or two or more units are integrated in one unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.

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

Based on the same concept as the above redundant path creation method, as shown in fig. 21, an embodiment of the present application further provides a schematic structural diagram of a communication device 2100. The apparatus 2100 may be configured to implement the method described in the method embodiment applied to the network device or the terminal device, and reference may be made to the description in the method embodiment. The apparatus 2100 may be in or be a network device or a terminal device.

The apparatus 2100 includes one or more processors 2101. The processor 2101 may be a general-purpose processor, a special-purpose processor, or the like. For example, a baseband processor, or a central processor. The baseband processor may be used to process communication protocols and communication data, and the central processor may be used to control a communication device (e.g., a base station, a terminal, or a chip), execute a software program, and process data of the software program. The communication device may include a transceiving unit to enable input (reception) and output (transmission) of signals. For example, the transceiver unit may be a transceiver, a radio frequency chip, or the like.

The apparatus 2100 comprises one or more processors 2101, and the one or more processors 2101 may implement the method of the network device or the terminal device in the above-described illustrated embodiments.

Alternatively, the processor 2101 may perform other functions in addition to the methods of the embodiments illustrated above.

Alternatively, in one design, the processor 2101 may execute instructions that cause the apparatus 2100 to perform the methods described in the method embodiments above. The instructions may be stored in whole or in part within the processor, such as instructions 2103, or in whole or in part in a memory 2102 coupled to the processor, such as instructions 2104, and together with

instructions

2103 and 2104, may cause apparatus 2100 to perform the methods described in the above method embodiments.

In yet another possible design, the communication apparatus 2100 may also include a circuit, which may implement the functions of the network device or the terminal device in the foregoing method embodiments.

In yet another possible design, the apparatus 2100 may include one or more memories 2102 having instructions 2104 stored thereon, which may be executed on the processor to cause the apparatus 2100 to perform the methods described in the above method embodiments. Optionally, the memory may further store data therein. Instructions and/or data may also be stored in the optional processor. For example, the one or more memories 2102 may store the corresponding relations described in the above embodiments, or related parameters or tables involved in the above embodiments, and the like. The processor and the memory may be provided separately or may be integrated together.

In yet another possible design, the apparatus 2100 may further include a transceiver unit 2105 and an antenna 2106. The processor 2101 may be referred to as a processing unit and controls a device (terminal or base station). The transceiver unit 2105 may be referred to as a transceiver, a transceiver circuit, a transceiver, or the like, and is used for implementing the transceiving function of the apparatus through the antenna 2106.

It should be noted that the processor in the embodiments of the present application may be an integrated circuit chip having signal processing capability. In implementation, the steps of the above method embodiments may be performed by integrated logic circuits of hardware in a processor or instructions in the form of software. The Processor may be a general purpose Processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), an off-the-shelf Programmable Gate Array (FPGA) or other Programmable logic device, discrete Gate or transistor logic device, or discrete hardware components. The various methods, steps, and logic blocks disclosed in the embodiments of the present application may be implemented or performed. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like. The steps of the method disclosed in connection with the embodiments of the present application may be directly implemented by a hardware decoding processor, or implemented by a combination of hardware and software modules in the decoding processor. The software module may be located in ram, flash memory, rom, prom, or eprom, registers, etc. storage media as is well known in the art. The storage medium is located in a memory, and a processor reads information in the memory and completes the steps of the method in combination with hardware of the processor.

It will be appreciated that the memory in the embodiments of the subject application can be either volatile memory or nonvolatile memory, or can include both volatile and nonvolatile memory. The non-volatile Memory may be a Read-Only Memory (ROM), a Programmable ROM (PROM), an Erasable PROM (EPROM), an Electrically Erasable PROM (EEPROM), or a flash Memory. Volatile Memory can be Random Access Memory (RAM), which acts as external cache Memory. By way of example, but not limitation, many forms of RAM are available, such as Static random access memory (Static RAM, SRAM), Dynamic Random Access Memory (DRAM), Synchronous Dynamic random access memory (Synchronous DRAM, SDRAM), Double Data Rate Synchronous Dynamic random access memory (DDR SDRAM), Enhanced Synchronous SDRAM (ESDRAM), Synchronous link SDRAM (SLDRAM), and Direct Rambus RAM (DR RAM). It should be noted that the memory of the systems and methods described herein is intended to comprise, without being limited to, these and any other suitable types of memory.

An embodiment of the present application further provides a computer-readable medium, on which a computer program is stored, where the computer program, when executed by a computer, implements the redundant path creation method described in any of the method embodiments applied to the network device or the terminal device.

The embodiments of the present application further provide a computer program product, which when executed by a computer implements the redundant path creation method described in any of the method embodiments applied to the network device or the terminal device.

In the above embodiments, the implementation may be wholly or partially realized by software, hardware, firmware, or any combination thereof. When implemented in software, may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When loaded and executed on a computer, cause the processes or functions described in accordance with the embodiments of the application to occur, in whole or in part. The computer may be a general purpose computer, a special purpose computer, a network of computers, or other programmable device. The computer instructions may be stored on a computer readable storage medium or transmitted from one computer readable storage medium to another, for example, from one website, computer, server, or data center to another website, computer, server, or data center via wire (e.g., coaxial cable, fiber optic, Digital Subscriber Line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device, such as a server, a data center, etc., that incorporates one or more of the available media. The usable medium may be a magnetic medium (e.g., a floppy Disk, a hard Disk, a magnetic tape), an optical medium (e.g., a Digital Video Disc (DVD)), or a semiconductor medium (e.g., a Solid State Disk (SSD)), among others.

The embodiment of the application also provides a processing device, which comprises a processor and an interface; the processor is configured to execute the redundant path creation method according to any of the method embodiments applied to the network device or the terminal device.

It should be understood that the processing device may be a chip, the processor may be implemented by hardware or software, and when implemented by hardware, the processor may be a logic circuit, an integrated circuit, or the like; when implemented in software, the processor may be a general-purpose processor implemented by reading software code stored in a memory, which may be integrated in the processor, located external to the processor, or stand-alone.

An embodiment of the present application further provides a communication system, where the communication system includes a session management function 21 that performs any of the above embodiments, and a user plane function 20 that receives the forwarding rule from the session management function 21.

The communication system may be applied to an industrial ethernet network, and the terminal device 11 may support redundant transmission and may not support redundant transmission.

Optionally, the communication system may further include a terminal device 10 configured to execute any of the above embodiments, a terminal device 12 configured to execute any of the above embodiments, and a terminal device 11 configured to execute any of the above embodiments. The terminal device 11 may support redundant transmission, and may not support redundant transmission.

Optionally, the communication system may further include a terminal device 14 served by the terminal device 12. The terminal device 14 may support redundant transmission and may not support redundant transmission.

Those of ordinary skill in the art will appreciate that the elements and algorithm steps of the examples described in connection with the embodiments disclosed herein may be embodied in electronic hardware, computer software, or combinations of both, and that the components and steps of the examples have been described in a functional general in the foregoing description for the purpose of illustrating clearly the interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

It is clear to those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described systems, apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.

In the several embodiments provided in the present application, it should be understood that the disclosed system, apparatus and method may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, a division of a unit is merely a logical division, and an actual implementation may have another division, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may also be an electric, mechanical or other form of connection.

Units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiments of the present application.

In addition, functional units in the embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.

Through the above description of the embodiments, those skilled in the art will clearly understand that the present application can be implemented in hardware, firmware, or a combination thereof. When implemented in software, the functions described above may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Computer-readable media includes both computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A storage media may be any available media that can be accessed by a computer. Taking this as an example but not limiting: computer-readable media can include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer. Furthermore, the method is simple. Any connection is properly termed a computer-readable medium. For example, if software is transmitted from a website, a server, or other remote source using a coaxial cable, a fiber optic cable, a twisted pair, a Digital Subscriber Line (DSL), or a wireless technology such as infrared, radio, and microwave, the coaxial cable, the fiber optic cable, the twisted pair, the DSL, or the wireless technology such as infrared, radio, and microwave are included in the fixation of the medium. Disk and disc, as used herein, includes Compact Disc (CD), laser disc, optical disc, Digital Versatile Disc (DVD), floppy Disk and blu-ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above are also included within the scope of computer-readable media.

In short, the above description is only a preferred embodiment of the present disclosure, and is not intended to limit the scope of the present disclosure. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for creating a redundant path, comprising:

a terminal device 10 receives a message 30 from a user plane function 20, the terminal device 10 serving a terminal device 11;

the terminal device 10 receives the message 30 from the terminal device 12;

the terminal device 10 de-duplicates the message 30 from the user plane function 20 and the message 30 from the terminal device 12;

the terminal device 10 sends the message 30 after the duplication removal to the terminal device 11.

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

the terminal device 10 receives a response 31 from the terminal device 11, where the response 31 corresponds to the deduplicated packet 30;

the terminal device 10 sends a response 32 to the terminal device 12, the response 32 corresponding to the message 30 from the terminal device 12.

3. The method according to claim 1 or 2, wherein if a failure occurs between the terminal device 10 and the user plane function 20, the method further comprises:

the terminal device 10 receives the message 35 from the terminal device 12, and sends the message 35 to the terminal device 11.

4. The method of any one of claims 1-3, further comprising:

the terminal device 10 receives first information from a session management function 21, where the first information indicates that a message from the user plane function 20 and a message from the terminal device 12 are deduplicated and then sent to the terminal device 11.

5. The method of claim 4, wherein the method further comprises:

the terminal device 10 receives second information from the session management function 21, the second information indicating establishment of a transmission path with the terminal device 12.

6. A method for creating a redundant path, comprising:

the session management function 21 acquires the terminal device 11 served by the terminal device 10;

the session management function 21 obtains the terminal device 14 served by the terminal device 12;

the session management function 21 determines that there is a correspondence between the terminal device 10 and the terminal device 12;

the session management function 21 sends a forwarding rule to the user plane function 20, where the forwarding rule indicates that a message is sent to the terminal device 11 through the terminal device 10 and a message is sent to the terminal device 14 through the terminal device 12.

7. The method of claim 6, wherein the forwarding rule further indicates a duplicate packet.

8. The method of claim 6 or 7, wherein the method further comprises:

the session management function 21 sends first information to the terminal device 10, where the first information indicates that the message from the user plane function 20 and the message from the terminal device 12 are deduplicated and then sent to the terminal device 11.

9. The method of any one of claims 6-8, further comprising:

the session management function 21 transmits second information indicating establishment of a transmission path with the terminal device 12 to the terminal device 10.

10. The method according to any of claims 6-9, wherein the session management function 21 obtaining the terminal device 11 served by the terminal device 10 comprises:

the session management function 21 receives information from the terminal device 11 of the terminal devices 10.

11. The method of any of claims 6-10, wherein the session management function 21 obtaining the terminal device 14 served by the terminal device 12 comprises:

the session management function 21 receives information from the terminal device 14 of the terminal devices 12.

12. The method according to any of claims 6-11, wherein the session management function 21 determining that there is a correspondence between the terminal device 10 and the terminal device 12 comprises:

the session management function 21 obtains the subscription data of the terminal device 10, where a subscription data indication of the terminal device 10 and the terminal device 12 have a corresponding relationship; and/or

The session management function 21 obtains the subscription data of the terminal device 12, where the subscription data indication of the terminal device 12 and the terminal device 10 have a corresponding relationship.

13. A method for creating a redundant path, comprising:

the terminal device 11 receives the message 30 from the terminal device 10;

the terminal device 11 receives the message 30 from the terminal device 12;

the terminal device 11 sends a response 33 to the terminal device 10, where the response 33 corresponds to the message 30 from the terminal device 10;

the terminal device 11 sends a response 34 to the terminal device 12, where the response 34 corresponds to the packet 30 from the terminal device 12.

14. The method according to claim 13, wherein if a failure occurs between the terminal device 10 and the user plane function 20 or if the terminal device 10 fails, the method further comprises:

the terminal device 11 receives the message 35 from the terminal device 12.

15. A method for creating a redundant path, comprising:

the terminal device 11 receives the message 30 from the terminal device 10;

the terminal device 11 receives the message 30 from the terminal device 12 through the terminal device 10;

the terminal device 11 sends a response 36 to the terminal device 10, where the response 36 corresponds to the message 30 from the terminal device 10;

the terminal device 11 sends a response 37 to the terminal device 12 through the terminal device 10, where the response 37 corresponds to the message 30 from the terminal device 12.

16. The method according to claim 15, wherein if a failure occurs between the terminal device 10 and the user plane function 20 or if the terminal device 10 fails, the method further comprises:

the terminal device 11 receives the message 35 from the terminal device 12.

17. A communication apparatus, comprising a processing unit and a transceiving unit;

18. The communications apparatus according to claim 17, wherein the transceiver unit is further configured to receive a response 31 from the terminal device 11, where the response 31 corresponds to the deduplicated message 30; sending a response 32 to the terminal device 12, the response 32 corresponding to the message 30 from the terminal device 12.

19. The communication apparatus according to claim 17 or 18, wherein the transceiver unit is further configured to receive a message 35 from the terminal device 12 and send the message 35 to the terminal device 11 if a failure occurs between the communication apparatus and the user plane function 20.

20. The communication apparatus according to any of claims 17 to 19, wherein the transceiving unit is further configured to receive first information from a session management function 21, where the first information indicates that the message from the user plane function 20 and the message from the terminal device 12 are to be deduplicated and then sent to the terminal device 11.

21. The communication apparatus according to claim 20, wherein the transceiver unit is further configured to receive second information from the session management function 21, the second information indicating establishment of a transmission path with the terminal device 12.

22. A communication apparatus, comprising a processing unit and a transceiving unit;

23. The communications apparatus of claim 22, the forwarding rule further indicates duplicate packets.

24. The communication apparatus according to claim 22 or 23, wherein the transceiver unit is further configured to send first information to the terminal device 10, where the first information indicates that the message from the user plane function 20 and the message from the terminal device 12 are to be deduplicated and then sent to the terminal device 11.

25. The communication apparatus according to any of claims 22-24, wherein the transceiver unit is further configured to send second information to the terminal device 10, the second information indicating establishment of a transmission path with the terminal device 12.

26. The communication apparatus according to any of the claims 22 to 25, wherein the transceiver unit is specifically configured to receive information from a terminal device 11 of the terminal devices 10.

27. The communication apparatus according to any of the claims 22 to 26, wherein the transceiver unit is specifically configured to receive information from a terminal device 14 of the terminal devices 12.

28. The communication apparatus according to any one of claims 22 to 27, wherein the processing unit is specifically configured to obtain subscription data of the terminal device 10, where the subscription data of the terminal device 10 indicates that there is a correspondence with the terminal device 12; and/or obtaining subscription data of the terminal device 12, where the subscription data of the terminal device 12 indicates that there is a corresponding relationship with the terminal device 10.

29. A communication apparatus, comprising a processing unit and a transceiving unit;

the processing unit is configured to determine the packet 30;

the transceiver unit is further configured to send a response 33 to the terminal device 10, where the response 33 corresponds to the packet 30 from the terminal device 10; sending a response 34 to the terminal device 12, the response 34 corresponding to the message 30 from the terminal device 12.

30. The communications apparatus as claimed in claim 29, wherein the transceiver unit is further configured to receive a message 35 from the terminal device 12 if a failure occurs between the terminal device 10 and the user plane function 20 or if the terminal device 10 fails.

31. A communication apparatus, comprising a processing unit and a transceiving unit;

the processing unit is configured to determine the packet 30;

32. The communications apparatus as claimed in claim 31, wherein the transceiver unit is further configured to receive a message 35 from the terminal device 12 if a failure occurs between the terminal device 10 and the user plane function 20 or if a failure occurs in the terminal device 10.

33. A communications apparatus, the apparatus comprising a processor, a transceiver, and a memory;

the transceiver is used for transmitting and receiving messages;

the memory to store computer program instructions;

the processor configured to execute some or all of the computer program instructions in the memory to perform the method of any one of claims 1-5, or to perform the method of any one of claims 6-12, or to perform the method of any one of claims 13-14, or to perform the method of any one of claims 15-16, by the transceiver.

34. A computer-readable storage medium having computer-readable instructions stored thereon which, when read and executed by a computer, cause the computer to perform the method of any one of claims 1-5, or perform the method of any one of claims 6-12, or perform the method of any one of claims 13-14, or perform the method of any one of claims 15-16.

35. A communication system, characterized in that the communication system comprises a session management function 21 performing the method according to any of claims 6-12, and the user plane function 20 receiving the forwarding rules from the session management function 21.