CN115696408A - User plane function disaster tolerance method and communication device - Google Patents

Abstract

The application discloses a user plane function disaster recovery method and a communication device. In the method, a disaster tolerance UPF receives first indication information, wherein the first indication information comprises a PDU conversation mark and a PDU conversation context information, and the context information comprises a forwarding surface IP address of a PDU conversation main UPF; when the main UPF has a forwarding plane fault, the disaster tolerance UPF forwards the message of the PDU session according to the IP address of the forwarding plane. In the method, a main UPF and a disaster tolerance UPF are set for a PDU session, when the main UPF is normal, the main UPF only transmits the message, and synchronizes the context information of the PDU session to the disaster tolerance UPF, when the main UPF has a failure on the forwarding plane, the disaster tolerance UPF takes over the message transmitting function of the PDU session quickly according to the context information of the PDU session, thereby ensuring the service reliability and avoiding the problem of bandwidth waste.

Description

User plane function disaster tolerance method and communication device

Technical Field

The present application relates to the field of communications technologies, and in particular, to a method and a device for disaster recovery of a user plane function.

Background

When a mobile terminal user accesses the internet or performs service processing through an APP, a Packet Data Unit (PDU) session needs to be established between the terminal and a network (or APP) so as to transmit a service packet. Through the PDU session, a bearer path between a terminal, a Radio Access Network (RAN), and a User Plane Function (UPF) is established. In this process, a Session Management Function (SMF) controls the UPF through the N4 interface.

In the fifth generation mobile communication system (5 th generation, 5G), an N3 interface represents an interface between a Radio Access Network (RAN) and a User Plane Function (UPF), and an N9 interface represents an interface between the UPF and the UPF.

In order to ensure the reliability of the N3/N9 interface, 2 different N3/N9 paths are established for the same PDU session, as shown in fig. 1, the RAN establishes different tunnels with the UPF via different forwarding UPFs (I-UPFs); alternatively, the RNA may establish different tunnels with different UPFs.

Taking the example that the message is forwarded by the I-UPF, for the uplink service message, the RAN duplicates 1 service message into 2, and the 2 messages carry the same serial number and are sent through an N3Tunnel (Tunnel) 1 and an N3Tunnel2, respectively. The 2I-UPFs respectively transmit the message, and the sequence number is not modified when the I-UPF transmits the message. And after receiving the message through the N9 interface, the UPF performs duplicate removal processing (only one message with the same serial number is reserved), and then transmits the original IP message without the GTP tunnel header through the N6 interface.

For downlink service messages, the UPF duplicates 1 service message into 2, and the 2 messages carry the same serial number and are respectively sent through N9Tunnel1 and N9Tunnel 2. The 2I-UPFs respectively transmit the message, and the sequence number is not modified when the I-UPF transmits the message. After receiving the message through the N3 interface, the RAN performs deduplication processing (only one message with the same sequence number is reserved).

By duplicating 1 service message into 2 service messages and respectively sending the service messages through different paths, the disaster tolerance of the middle path is realized, and the forwarding of the service messages is not influenced due to the fault of any I-UPF. However, the disaster recovery method requires the RAN to support dual-transmission selective reception, and each packet is transmitted twice, which occupies a large bandwidth, and is not suitable for large-scale packet transmission or data transmission of a large number of users.

Disclosure of Invention

The embodiment of the application provides a user plane function disaster recovery method, a communication device and a system, which are used for realizing the disaster recovery of UPF faults and simultaneously avoiding the problem of bandwidth waste caused by repeated sending of each message through different paths.

In a first aspect, an embodiment of the present application provides a method for disaster recovery of a user plane function, including: receiving first indication information by a disaster tolerance UPF, wherein the first indication information comprises context information of a PDU session of a packet data unit, and the context information comprises an IP address of a forwarding plane of a main UPF of the PDU session; and when the forwarding plane of the main UPF fails, the disaster tolerance UPF forwards the message of the PDU session according to the IP address of the forwarding plane of the main UPF.

In the method, a main UPF and a disaster tolerance UPF are set for a PDU session, when the main UPF can work normally, the main UPF only transmits the message, and synchronizes the context information of the PDU session to the disaster tolerance UPF, so that when the main UPF has a failure on the transmitting side, the disaster tolerance UPF can quickly take over the message transmitting function of the PDU session according to the context information of the PDU session, thereby ensuring the reliability of the N3/N9 interface. In addition, the method does not need the RAN to support double-transmission selective reception, reduces the performance requirement of the RAN, does not need to transmit each message for multiple times, and solves the problem that redundant information occupies a large amount of bandwidth.

In a possible implementation manner, the receiving, by the disaster recovery UPF, first indication information includes: the disaster tolerance UPF receives first indication information sent by a master UPF of the PDU session; or, the disaster recovery UPF receives the first indication information sent by the session management function SMF. In the above solution, the disaster tolerance UPF obtains the first indication information in two ways, one is that the main UPF sends the first indication information to the disaster tolerance UPF, and the SMF does not need to sense the existence of the disaster tolerance UPF, and the other is that the SMF sends the first indication information to the disaster tolerance UPF, so that the main UPF does not need to sense the existence of the disaster tolerance UPF.

In a possible implementation manner, the receiving, by the disaster recovery UPF, first indication information sent by a master UPF of the PDU session includes: the disaster tolerance UPF receives a session establishment request sent by a master UPF of the PDU session, wherein the session establishment request comprises the first indication information; or, the disaster recovery UPF receives a session modification request sent by a master UPF of the PDU session, where the session modification request includes the first indication information. In this implementation, the primary UPF may send the first indication information to the disaster tolerance UPF through a request or notification message.

In a possible implementation manner, the receiving, by the disaster recovery UPF, first indication information sent by a master UPF of the PDU session includes: and the database DB in the disaster tolerance UPF receives first indication information sent by the DB in the master UPF of the PDU conversation. In this implementation, the master UPF may send the first indication information to the disaster tolerance UPF in a DB data synchronization manner.

In a possible implementation manner, the context information of the PDU session is the basic service context information of the PDU session; when a failure of a forwarding plane occurs in a primary UPF of the PDU session, the method further comprises: the disaster tolerance UPF receives second indication information sent by the SMF, wherein the second indication information comprises value added service context information of the PDU session; and the disaster tolerance UPF performs service processing on the message of the PDU session according to the value added service context information. In the implementation mode, when the main UPF can work normally, the disaster recovery UPF can only backup the basic service context information of the PDU conversation, so that the main UPF can quickly take over the forwarding function when the main UPF fails, but the redundant information is not stored; and after the main UPF fails, the context information of the value added service is acquired from the SMF, so that the message of the PDU session is processed.

In one possible implementation, after a failure of a forwarding plane occurs in a primary UPF of the PDU session, the method further includes: and the disaster tolerance UPF sends first routing indication information to a router, wherein the first routing information comprises a forwarding plane IP address of the main UPF, so that the router forwards the message in the PDU session to the disaster tolerance UPF according to the forwarding plane IP address. In the implementation mode, when the main UPF fails, the disaster recovery UPF adopts the same forwarding plane IP address as the main UPF to realize the forwarding function of the PDU session message, and the router sends the PDU session message to the disaster recovery UPF according to the IP address in the first routing indication information.

In one possible implementation, the method further includes: the disaster tolerance UPF sends second routing indication information to a router, wherein the second routing indication information comprises a forwarding plane IP address of the main UPF and priority indication information, and the priority indication information is used for indicating the routing priority of the disaster tolerance UPF for the forwarding plane IP address; and for the IP address of the forwarding plane, the routing priority of the disaster recovery UPF is lower than that of the main UPF. In this implementation, after acquiring the forwarding IP address of the main UPF, the disaster tolerant UPF may send the second routing indication information to the router, so that the router preferentially sends the message to the main UPF when the forwarding plane of the main UPF is normal, and sends the message to the disaster tolerant UPF when the forwarding plane of the main UPF fails.

In one possible implementation, the forwarding plane IP address includes: the IP address of the UPF and the wireless access network interface, and the IP address of the UPF and the data network interface; or, the IP address of the UPF and the wireless access network interface, and the IP address of the UPF and the UPF interface; or the IP addresses of the UPF and UPF interfaces, and the IP addresses of the UPF and data network interfaces. If the PDU session does not have I-UPF, the forwarding plane IP address may include an IP address between the UPF and the radio access network interface and an IP address between the UPF and the data network interface; if there is an I-UPF in the PDU session and the primary UPF is the I-UPF, the forwarding plane IP address may include an IP address between the UPF and the radio access network interface and an IP address between the UPF and the UPF interface; if an I-UPF exists in the PDU session and the master UPF is a UPF directly connected to the DN, the forwarding plane IP address may include an IP address between the UPF and the UPF interface and an IP address between the UPF and the data network interface.

In a possible implementation manner, the UPF and radio access network interface is an N3 interface, the UPF and data network interface is an N6 interface, and the UPF and UPF interface is an N9 interface.

In a possible implementation manner, the routing indication information further includes IP addresses of the main UPF and SMF interfaces, so that the router forwards control plane information sent by the SMF according to the control plane IP address. In this implementation, the first routing indication information or the second routing indication information may further include a control plane IP address of the main UPF, that is, the disaster tolerance UPF can not only take over the function of the main UPF on the forwarding plane, but also take over the function of the main UPF on the control plane, and can receive control plane information from the SMF.

In one possible implementation, the method further includes: when a link between a master UPF and an SMF of the PDU conversation fails and a forwarding plane is normal, the disaster tolerance UPF receives control plane information of the PDU conversation sent by the SMF, and the control plane information comprises context information after the PDU conversation is updated; and the disaster tolerance UPF sends the updated context information to a main UPF of the PDU conversation. In this implementation, if the main UPF control plane fails but the forwarding plane is normal, the disaster recovery UPF may receive the control plane information of the SMF, and send the updated context information to the main UPF, so that the main UPF continues to complete the function of the control plane.

In a second aspect, an embodiment of the present application provides a method for disaster recovery of a user plane function, including: a master UPF determines context information of a Packet Data Unit (PDU) session, wherein the context information of the PDU session comprises a forwarding plane IP address of the master UPF; and the master UPF sends first indication information to the disaster recovery UPF of the PDU session, wherein the first indication information comprises the context information of the PDU session. In the above scheme, the main UPF sends the forwarding plane IP address to the disaster recovery UPF, so that when the main UPF sends a failure to the forwarding plane, the disaster recovery UPF can take over the main UPF to forward the message of the PDU session.

In a possible implementation manner, the sending, by the master UPF, first indication information to the disaster recovery UPF of the PDU session includes: a session establishment request sent by the master UPF to the disaster recovery UPF, wherein the session establishment request comprises the first indication information; or, the session modification request sent by the master UPF to the disaster recovery UPF includes the first indication information. In this implementation, the master UPF may send the first indication information to the disaster tolerance UPF through a request or a notification message.

In a possible implementation manner, the sending, by the master UPF, first indication information to the disaster recovery UPF of the PDU session includes: and the database DB in the main UPF sends the first indication information to the DB in the disaster tolerance UPF. In this implementation, the master UPF may send the first indication information to the disaster tolerance UPF in a DB data synchronization manner.

In a possible implementation manner, the context information of the PDU session is basic service context information of the PDU session, and the basic service context information is necessary context information when a packet in the PDU session is forwarded. In the implementation mode, when the main UPF can work normally, the disaster recovery UPF can only backup the basic service context information of the PDU session, so that the main UPF can quickly take over the forwarding function when the main UPF fails, but the redundant information is not stored.

In one possible implementation, the method further includes: the main UPF receives a session establishment request sent by the SMF, wherein the request comprises a UPF and data network interface IP address and an IP resource group identifier; and the main UPF sends a session establishment response to the SMF according to the session establishment request, wherein the response comprises UPF and wireless access network interface IP addresses, and the UPF and the wireless access network interface IP addresses belong to the IP resource group corresponding to the IP resource group identifier. In this implementation, a plurality of IP resource groups may be preset to facilitate management of IP addresses; the SMF can allocate the IP address between the primary UPF and the DN for the primary UPF and indicate the IP resource group to which the IP address belongs, and the primary UPF determines the IP addresses of other forwarding planes belonging to the IP resource group by itself.

In one possible implementation, the method further includes: the main UPF sends first routing indication information to a router, wherein the first routing indication information comprises a forwarding plane IP address of the main UPF and priority indication information, the priority indication information is used for indicating the routing priority of the main UPF for the forwarding plane IP address, the routing priority of the main UPF for the forwarding plane IP address is higher than that of the disaster recovery UPF, and the first routing indication information is used for indicating the router to forward a message according to the forwarding plane IP address and the priority indication information. In this implementation, the main UPF and the disaster tolerance UPF may both send routing indication information to the router, including forwarding plane IP addresses and priority information, and the forwarding plane IP addresses sent by the main UPF and the disaster tolerance UPF are the same, but the priorities are different; the router sends the message to the main UPF preferentially when the forwarding plane of the main UPF is normal, and sends the message to the disaster recovery UPF after the forwarding plane of the main UPF fails.

In one possible implementation, the method further includes: when the link between the main UPF and the SMF is failed and the forwarding plane is normal, the main UPF receives the updated context information of the PDU session sent by the disaster recovery UPF; and the master UPF processes the message in the PDU conversation according to the updated context information. In this implementation, if the primary UPF control plane fails but the forwarding plane is normal, the disaster recovery UPF may receive the control plane information of the SMF, and send the updated context information to the primary UPF, so that the primary UPF continues to complete the function of the forwarding plane.

In a possible implementation manner, the receiving, by the master UPF, the updated context information of the PDU session sent by the disaster recovery UPF includes: and the DB in the main UPF receives the context information after the PDU session is updated, which is sent by the DB in the disaster tolerance UPF. In this implementation, although the disaster tolerance UPF receives the updated context information sent by the SMF, the disaster tolerance UPF may not store the updated context information, and therefore, the master UPF may send the updated context information to the BD of the disaster tolerance UPF in a DB data synchronization manner, so that the disaster tolerance UPF stores the information and forwards the packet according to the information when disaster tolerance is required.

In a third aspect, an embodiment of the present application provides a method for disaster recovery of a user plane function, including: a Session Management Function (SMF) determines context information of a Packet Data Unit (PDU) session, wherein the context information comprises a forwarding plane IP address of a main UPF of the PDU session; and the SMF sends a first session establishment request to the disaster tolerance UPF of the PDU session, wherein the first session establishment request comprises the context information of the PDU session. In the above scheme, the SMF sends the IP address of the forwarding plane of the primary UPF to the disaster-tolerant UPF, so that when the forwarding plane sent by the primary UPF fails, the disaster-tolerant UPF can take over the primary UPF to forward the message of the PDU session.

In one possible implementation, before the SMF determines context information of a PDU session, the method further includes: the SMF sends a second session establishment request to a primary UPF of the PDU session; and the SMF receives a second session establishment response sent by the main UPF, wherein the second session establishment response comprises the forwarding plane IP address of the main UPF. In this implementation, the SMF may obtain the forwarding plane IP address of the primary UPF through a session establishment procedure with the primary UPF.

In a possible implementation manner, the second session establishment request includes an IP address and an IP resource group identifier of a UPF and data network interface allocated to the master UPF; and the forwarding surface IP address in the second session establishment response belongs to the IP resource group corresponding to the IP resource group identifier. In this implementation, a plurality of IP resource groups may be preset to facilitate management of IP addresses; the SMF can allocate the IP address between the primary UPF and the DN for the primary UPF and indicate the IP resource group to which the IP address belongs, and the primary UPF determines the IP addresses of other forwarding planes belonging to the IP resource group by itself.

In one possible implementation manner, when the control plane failure occurs in the master UPF, the method further includes: and the SMF sends the control information of the PDU session to the disaster tolerance UPF. In this implementation, if the main UPF control plane fails but the forwarding plane is normal, the SMF may send control plane information (e.g., updated context information) to the disaster tolerance UPF, and the disaster tolerance UPF replaces the functions of the main UPF on the control plane and the forwarding plane, or the disaster tolerance UPF sends the updated context information to the main UPF, so that the main UPF continues to complete the function of the forwarding plane.

In a fourth aspect, an embodiment of the present application provides a communication apparatus, which includes a module/unit that performs the method of the first aspect and any one of the possible implementation manners of the first aspect; these modules/units may be implemented by hardware, or by hardware executing corresponding software.

For example, the communication apparatus may include a transceiver module and a processing module, the transceiver module may be configured to perform information transceiving processing in various designs of the first aspect, such as receiving first indication information, forwarding a packet of the PDU session, and the like, and the processing module is configured to control the transceiver module to perform transceiving operation, and the like.

In a fifth aspect, an embodiment of the present application provides a communication apparatus, which includes a module/unit for performing the method of any one of the second aspect and the possible implementation manner of the second aspect; these modules/units may be implemented by hardware, or by hardware executing corresponding software.

Illustratively, the communications apparatus may include a transceiver module and a processing module, the processing module being configured to perform processing functions in the various designs of the second aspect, such as determining context information of a packet data unit, PDU, session; a transceiver module, configured to perform information transceiving processing in each design of the second aspect, for example, send first indication information to a disaster recovery UPF of the PDU session.

In a sixth aspect, an embodiment of the present application provides a communication apparatus, where the apparatus includes a module/unit that performs the method according to any one of the foregoing third aspect and possible implementation manners of the third aspect; these modules/units may be implemented by hardware, or by hardware executing corresponding software.

For example, the communication apparatus may include a processing module and a transceiver module, the processing module is configured to perform the processing function in each design of the third aspect, such as the determining module is configured to determine the context information of the PDU session; the transceiver module is configured to perform transceiving operations in each design of the third aspect, for example, sending a first session establishment request to a disaster recovery UPF of the PDU session.

In a seventh aspect, an embodiment of the present application provides a communication apparatus, including: a processor, and a memory and a communication interface respectively coupled to the processor; the communication interface is used for communicating with other equipment; the processor is configured to execute instructions or programs in the memory and to perform the method according to the first aspect and any one of the possible implementations of the first aspect via the communication interface.

In an eighth aspect, an embodiment of the present application provides a communication apparatus, including: a processor, and a memory and a communication interface each coupled to the processor; the communication interface is used for communicating with other equipment; the processor is configured to execute the instructions or programs in the memory and to perform the method according to the second aspect and any one of the possible implementations of the second aspect via the communication interface.

In a ninth aspect, an embodiment of the present application provides a communication apparatus, including: a processor, and a memory and a communication interface respectively coupled to the processor; the communication interface is used for communicating with other equipment; the processor is configured to execute the instructions or programs in the memory and to perform the method according to the third aspect and any one of the possible implementation manners of the third aspect through the communication interface.

In a tenth aspect, an embodiment of the present application provides a computer-readable storage medium, having stored thereon computer-readable instructions, which, when executed on a computer, cause the method according to the first aspect, the second aspect, the third aspect, and any possible implementation manner thereof to be performed.

In an eleventh aspect, embodiments of the present application provide a computer program product containing instructions that, when run on a computer, cause a method as described in the first aspect, the second aspect, the third aspect, and any possible implementation thereof to be performed.

Technical effects that may be brought by any one of the possible designs of any one of the fourth aspect to the eleventh aspect may be described with reference to technical effects that may be brought by any one of the possible designs of any one of the first aspect to the third aspect, and repeated description is omitted here.

Drawings

Fig. 1 is a schematic diagram of a UPF disaster recovery method according to an embodiment of the present application;

fig. 2 is a schematic diagram of a network architecture according to an embodiment of the present application;

fig. 3 is a schematic diagram of another network architecture provided in the embodiment of the present application;

fig. 4 is a schematic flowchart of a UPF disaster recovery method provided in an embodiment of the present application;

fig. 5 is a schematic flowchart of a process in which a primary UPF sends context information to a disaster recovery UPF according to an embodiment of the present application;

fig. 6 is a schematic flowchart of another process, provided in an embodiment of the present application, for a master UPF to send context information to a disaster recovery UPF;

fig. 7 is a schematic flowchart of a process of sending context information to a disaster recovery UPF by an SMF according to an embodiment of the present application;

fig. 8 is a schematic flowchart of a work flow of replacing a main UPF by a disaster recovery UPF according to an embodiment of the present application;

fig. 9 is a schematic diagram of an IP resource group in a 1+1 active/standby mode according to an embodiment of the present application;

fig. 10 is a schematic diagram of an IP resource group in 1+1 mutual assistance mode according to an embodiment of the present application;

fig. 11 is a schematic diagram of an IP resource group in an N +1 mode according to an embodiment of the present application;

fig. 12 is a schematic diagram of an IP resource group in an N way pool mutual assistance mode according to an embodiment of the present application;

fig. 13 is a schematic diagram illustrating an SMF allocating an N6 interface IP address and an IP resource group according to an embodiment of the present application;

fig. 14 is a schematic diagram illustrating a control plane being switched to a disaster tolerance UPF according to an embodiment of the present application;

fig. 15 is a schematic diagram illustrating a control plane switching and a forwarding plane not changing according to an embodiment of the present application;

fig. 16 is a schematic diagram illustrating another example of a control plane switching and a forwarding plane not changing according to the present invention;

fig. 17 is a schematic structural diagram of a communication device according to an embodiment of the present application;

fig. 18 is a schematic structural diagram of another communication device according to an embodiment of the present application.

Detailed Description

In order to realize that when a UPF fails, other UPFs can take over fast service, one implementation is to duplicate one message into 2 messages, and send the messages through different paths, so as to realize disaster recovery configuration of transmission paths. However, the disaster recovery method is not suitable for a large-scale message transmission or a service scenario of a large amount of user data transmission.

In order to implement the disaster tolerance of the UPF and solve the problem that a repeatedly transmitted message occupies a large bandwidth, an embodiment of the present application provides a UPF disaster tolerance method. The method may be applied in a network architecture as described in fig. 2 or fig. 3. As shown in fig. 2 or fig. 3, the network architecture may include the following units or devices:

a terminal, to which the present application relates, may include a handheld device having a wireless communication function, a vehicle-mounted device, a wearable device, a computing device or other processing device connected to a wireless modem, and various forms of User Equipment (UE), a Mobile Station (MS), a terminal device (terminal equipment), and the like. Fig. 2 and 3 illustrate a UE.

Radio Access Networks (RANs) are used to implement radio-related functions. The radio access network, which may also be referred to as an access network device or a base station, is used to access the terminal device to the wireless network. The radio access network may be a base station (base station), an evolved NodeB (eNodeB) in an LTE system or an evolved LTE system (LTE-Advanced, LTE-a), a next generation NodeB (gNB) in a 5G communication system, a Transmission Reception Point (TRP), a Base Band Unit (BBU), a WiFi Access Point (AP), a base station in a future mobile communication system or an access node in a WiFi system, and the like. The radio access network may also be a module or unit that performs part of the functions of the base station, and may be, for example, a Centralized Unit (CU) or a Distributed Unit (DU). The embodiment of the present application does not limit the specific technology and the specific device form used by the radio access network. For example, in one network structure, the radio access network may be a CU node, or a DU node, or a radio access network including a CU node and a DU node. Specifically, the CU node is configured to support Radio Resource Control (RRC), packet Data Convergence Protocol (PDCP), service Data Adaptation Protocol (SDAP), and other protocols; the DU node is configured to support a Radio Link Control (RLC) layer protocol, a Medium Access Control (MAC) layer protocol, and a physical layer protocol.

The main functions of the UPF include: routing and transmission of data packets, packet detection, service usage reporting, qoS processing, lawful interception, uplink packet detection, downlink data packet storage and other user plane related functions. The I-UPF, which is similar in function to the UPF, may also forward messages to the UPF.

Access and mobility management function (AMF), the main functions include: connection management, mobility management, registration management, access authentication and authorization, reachability management, security context management, and other access and mobility related functions.

Session Management Function (SMF), whose main functions include: session management (e.g., session setup, modification, and release, including tunnel maintenance between the UPF and the AN), selection and control of the UPF, SSC (Service and Session Continuity) mode selection, roaming, and other Session-related functions.

Policy Control Function (PCF), whose main functions include: unified policy making, providing policy control, and obtaining subscription information related to policy decision from the UDR.

A Data Network (DN) has a main function of providing specific data services, such as operator services, internet access or third party services.

It should be understood that fig. 2 and fig. 3 are 5G mobile communication systems as examples, and exemplarily provide a network architecture to which the embodiments of the present application can be applied, and a network architecture in practical application may include more or less network elements than those shown in fig. 2 and fig. 3.

The UPF according to the embodiment of the present application may be a UPF in a 5G mobile communication system, or may be a network element having a user plane function in a future communication system, and the UPF in the 5G mobile communication system is hereinafter exemplified.

The interfaces between the UPF and the radio access network in the embodiments of the present application are all exemplified by an N3 interface between the UPF and the RAN in a 5G mobile communication system; the interface between the UPF and the data network is, for example, an N6 interface between the UPF and the DN in the 5G mobile communication system; the interface between the UPF and the UPF takes an N9 interface in a 5G mobile communication system as an example; the interface between the UPF and the network element with session management function is, for example, an N4 interface between the UPF and the SMF in a 5G mobile communication system. It should be understood that when the applicable scenario is other mobile communication systems, the above-mentioned interface may be an interface between corresponding functional network elements in the system.

Fig. 4 is a user plane function disaster recovery method provided in the embodiment of the present application, and as shown in fig. 4, the method may include the following steps:

step 401, the disaster recovery UPF receives a first indication information, where the first indication information includes context information of the PDU session, and the context information includes a forwarding plane IP address of the PDU session master UPF.

In the embodiment of the application, a main UPF and one or more disaster-tolerant UPFs are set for the PDU session, the disaster-tolerant UPF is used as a standby device of the main UPF, and when the main UPF fails, the disaster-tolerant UPF replaces the main UPF to execute the function of the main UPF so as to avoid the interruption of user services.

The primary UPF may be the I-UPF in the PDU session or the UPF that communicates directly with the DN in the PDU session; correspondingly, if the primary UPF is the I-UPF in the PDU session, the disaster recovery UPF is used as the standby I-UPF in the PDU session, and if the primary UPF is the UPF directly communicating with the DN in the PDU session, the disaster recovery UPF is used as the standby UPF directly communicating with the DN in the PDU session.

In order to quickly take over the main UPF when the main UPF fails, the disaster recovery UPF may obtain context information of the PDU session carried by the main UPF in advance. The context information comprises the IP address of the main UPF of the PDU conversation on the forwarding surface, so that when the main UPF fails, the disaster recovery UPF can receive and forward the message of the PDU conversation according to the acquired IP address of the forwarding surface of the main UPF, thereby avoiding the interruption of the PDU conversation service.

The identification of the PDU session in the first indication information may be an ID of the PDU session, or may be other information that can be used to identify the PDU session.

Step 402, when the primary UPF of the PDU conversation has a forwarding plane fault, the disaster recovery UPF forwards the message of the PDU conversation according to the IP address of the forwarding plane.

The UPF has a control plane and a forwarding plane. The control plane comprises communication between the UPF and the SMF or other network elements, and is mainly used for transmitting control signaling; the forwarding plane includes communication between the UPF and RAN, UPF, DN, etc., and is mainly used for transmission of service messages.

If the forwarding plane of the primary UPF fails, the primary UPF cannot send the message to the DN, which causes service interruption. Therefore, in order to avoid service interruption, when the primary UPF fails on the forwarding plane, the disaster recovery UPF forwards the PDU session packet according to the acquired context information.

Optionally, the disaster recovery UPF may determine whether the forwarding plane failure occurs in the main UPF through heartbeat detection. For example, the disaster recovery UPF may periodically generate a heartbeat detection request to the main UPF, and if a heartbeat detection response returned by the main UPF can be received, the main UPF is considered to be normal on the forwarding plane, and if the heartbeat detection response cannot be normally received, the main UPF is considered to have a failure on the forwarding plane.

It should be understood that the disaster recovery UPF here forwards the packet, either directly or by first processing the packet and sending the processed packet to the DN or other network elements.

In the above embodiment of the present application, a master UPF and a disaster recovery UPF are set for one PDU session, when the master UPF can work normally, only the master UPF forwards a message, and synchronizes context information of the PDU session to the disaster recovery UPF, so that when a forwarding plane failure occurs in the master UPF, the disaster recovery UPF can quickly take over a message forwarding function of the PDU session according to the context information of the PDU session, thereby ensuring reliability of an N3/N9 interface. In addition, in the implementation shown in fig. 1, the RAN needs to copy and send each packet to I-UPF1 and I-UPF2, respectively, and this approach requires the RAN to support dual-transmission selective reception, and each packet is sent twice, which occupies more bandwidth; after the embodiment of the application is implemented, the RAN does not need to copy and send the message to different UPFs, the performance requirement on the RAN can be effectively reduced, each message does not need to be sent for multiple times, and the problem that redundant information occupies a large amount of bandwidth is solved.

Optionally, the forwarding plane IP address may include an N3 interface IP address and an N6 interface IP address, for example, in the absence of I-UPF, the forwarding plane of the UPF mainly includes a communication link formed by RAN-UPF-DN, and the N3 interface IP address and the N6 interface IP address are required to be used for forwarding a packet; or, the forwarding plane IP address may also include an N3 interface IP address and an N9 interface IP address, for example, if the primary UPF is I-UPF, the forwarding plane mainly includes a communication link formed by RAN-I-UPF, and the message forwarding needs to use the N3 interface IP address and the N9 interface IP address; alternatively, the forwarding plane IP address may also include an N9 interface IP address and an N6 interface IP address, for example, in a case where the communication link includes an I-UPF and the master UPF is not an I-UPF, the forwarding plane mainly includes a communication link formed by an I-UPF-DN, and the N9 interface IP address and the N6 interface IP address are used for forwarding a message.

The context information of the PDU session can be further divided into basic service context information and value added service context information. The basic service context information may be necessary information when forwarding a packet in a PDU session, such as a primary UPF forwarding plane IP address (N3 interface IP address, N6 interface IP address, N9 interface IP address), a tunnel end point identification (TEID), and the like. The value added service context information may be information that may be used when processing and forwarding a packet in a PDU session, such as service charging information, quality of service (QoS), and the like.

In some embodiments, the context information in the first indication information may include both basic service context information and value-added service context information, so that when a forwarding plane failure occurs in the main UPF, the disaster recovery UPF may quickly take over a task of the main UPF to implement processing and forwarding of the packet.

In other embodiments, the context information in the first indication information may only include basic service context information, and after the primary UPF sends a forwarding plane failure, the disaster tolerance UPF obtains the value-added service context information of the PDU session again. For example, the primary UPF sends the basic service context information to the disaster tolerance UPF; and after determining that the forwarding plane of the main UPF fails, the disaster tolerance UPF requests the SMF to acquire the value added service context information of the PDU session. For another example, the SMF first sends the basic service context information to the disaster tolerance UPF, and when the forwarding plane of the main UPF fails, the SMF sends the value-added service context information to the disaster tolerance UPF. The embodiment enables the disaster tolerant UPF to quickly take over the main UPF to complete the forwarding of the message after the main UPF has a forwarding plane fault, but the disaster tolerant UPF does not store too much redundant information.

In the embodiment of the present application, in order to solve the disaster tolerance problem of the UPF, the main UPF and the disaster tolerance UPF may have the following multiple modes:

1+1 master/standby mode, that is, a master UPF and a disaster recovery UPF are set for a PDU session.

1+1 mutual assistance mode, in which the primary UPF of a first part of PDU sessions (which may include one or more PDU sessions) is UPF1, the primary UPF of a second part of PDU sessions (which may include one or more PDU sessions) is UPF2, and UPF2 is set as the disaster tolerant UPF of the first part of PDU sessions, and UPF1 is set as the disaster tolerant UPF of the second part of PDU sessions.

The N +1 mode, that is, one UPF is taken as a disaster tolerance UPF of N UPFs. In this mode, the disaster tolerant UPF may acquire the basic service context information first, and then acquire the value added service context information after the forwarding plane failure occurs in the main UPF, so as to reduce the storage burden of the disaster tolerant UPF.

The method comprises the following steps that (1) a way pool mutual-aid mode is adopted, in the mode, a main UPF of a PDU conversation of a first part is UPF1, a main UPF of a PDU conversation of a second part is UPF2, and a main UPF of an PDU conversation of an Nth part … is UPF N; if the UPF1 fails, the first part of PDU session is distributed to a plurality of UPFs (which may include one or more of UPF2, …, UPF N) in the mode, and if the UPF2 fails, the second part of PDU session is distributed to a plurality of UPFs (which may include one or more of UPF1, UPF3, …, UPF N) in the mode.

No matter which mode is adopted, for the disaster recovery UPF, a corresponding disaster recovery method is performed according to the embodiment shown in fig. 4.

In step 401, the manner of acquiring the first indication information by the disaster recovery UPF may be a variety of manners.

In one possible implementation, the first indication information may be sent by the master UPF to the disaster recovery UPF. Further, the primary UPF may send the first indication information to the disaster tolerance UPF through a request message or other message. For example, in the specific embodiment shown in fig. 5, after the master UPF receives a Packet Forwarding Control Protocol (PFCP) session establishment request sent by the SMF, the master UPF may send the session establishment request to the disaster recovery UPF, where the session establishment request includes the first indication information; although the primary UPF is shown to send the session establishment request to the disaster tolerant UPF after replying the PFCP session establishment response to the SMF, the primary UPF may send the session establishment request to the disaster tolerant UPF before replying the PFCP session establishment response to the SMF. After receiving the PFCP session modification request sent by the SMF, the primary UPF may send a session modification request to the disaster recovery UPF, where the session modification request may also include the first indication information; although the primary UPF is shown to send the session modification request to the disaster-tolerant UPF after replying the PFCP session modification response to the SMF, the primary UPF may send the session modification request to the disaster-tolerant UPF before replying the PFCP session modification response to the SMF. The session establishment and modification may cause a change in the PDU session context information, and therefore, the session establishment request and the session modification request sent by the master UPF to the disaster recovery UPF may include the first indication information. After receiving a PFCP session deletion request sent by the SMF, the primary UPF may send a session deletion request to the disaster recovery UPF, so that the disaster recovery UPF releases the relevant information of the session; although the primary UPF is shown to send the session deletion request to the disaster-tolerant UPF after replying the PFCP session deletion response to the SMF, the primary UPF may send the session deletion request to the disaster-tolerant UPF before replying the PFCP session deletion response to the SMF.

Alternatively, the first indication information may be transmitted from the DB in the master UPF to the DB in the disaster tolerance UPF in a DB record table synchronization manner. For example, in the specific embodiment shown in fig. 6, after the service processing module in the master UPF receives the PFCP session establishment request sent by the SMF, the service processing module records the context information of the PDU session into the DB of the master UPF, then the DB of the master UPF synchronizes the context information of the PDU session into the DB of the disaster tolerance UPF, and then the DB of the disaster tolerance UPF sends the context information of the PDU session to the service processing module of the disaster tolerance UPF; although the figure shows that the traffic processing module of the master UPF sends the context information of the PDU session to the DB after replying the PFCP session establishment response to the SMF, the DB of the master UPF may send the context information of the PDU session to the DB before replying the PFCP session establishment response to the SMF. After a service processing module in a main UPF receives a PFCP session modification request sent by an SMF, the service processing module records the context information of the modified PDU session into a DB of the main UPF, then the DB of the main UPF synchronizes the context information of the modified PDU session into the DB of a disaster tolerance UPF, and then the DB of the disaster tolerance UPF sends the context information of the modified PDU session to the service processing module of the disaster tolerance UPF; although the figure shows that the traffic processing module of the master UPF sends the context information of the PDU session to the DB after replying the PFCP session modification response to the SMF, the DB of the master UPF may send the context information of the PDU session to the DB before replying the PFCP session modification response to the SMF. When a service processing module in a main UPF receives a PFCP session deletion request sent by an SMF, the service processing module in the main UPF informs a DB in the main UPF to delete the context information of the PDU session, then the DB in the main UPF informs the DB in a disaster tolerance UPF to delete the context information of the PDU session, and then the DB in the disaster tolerance UPF informs the service processing module in the disaster tolerance UPF to delete the context information of the PDU session; although the service processing module of the master UPF is shown to notify the DB of deleting the context information of the PDU session after replying the PFCP session deletion response to the SMF, the DB of the master UPF may notify the DB of deleting the context information of the PDU session in the disaster tolerant UPF before replying the PFCP session deletion response to the SMF.

In another possible implementation manner, the first indication information received by the disaster tolerance UPF in step 401 shown in fig. 4 may also be sent by the SMF. For example, in the specific embodiment shown in fig. 7, the SMF may send a PFCP session establishment request to the primary UPF, and the primary UPF replies a PFCP session establishment response to the SMF, where the response includes forwarding plane address information (such as N3 interface IP address, N6 interface IP address, TEID, etc.) of the primary UPF; then, the SMF sends a PFCP session establishment request to the disaster tolerance UPF, which may be understood as the first indication information in step 401 shown in fig. 4, where the PFCP session establishment request may include forwarding plane address information sent by the main UPF, and the disaster tolerance UPF replies a PFCP session establishment response to the SMF. Correspondingly, when the sending of the subsequent PDU session context information is changed, the SMF sends a PFCP session modification request to the main UPF and receives a PFCP session modification response replied by the main UPF; the SMF also sends a PFCP session modification request to the disaster tolerant UPF and receives a PFCP session modification response replied by the disaster tolerant UPF. When the PDU session needs to be deleted, the SMF sends a PFCP session deletion request to the main UPF and receives a PFCP session deletion response replied by the main UPF; the SMF also sends a PFCP session deletion request to the disaster tolerant UPF and receives a PFCP session deletion response replied by the disaster tolerant UPF. In the embodiment shown in fig. 7, part of the context information, such as the N3 interface IP address, the N6 interface IP address, the TEID, etc., may be autonomously determined by the master UPF; in other embodiments, all or part of this information may be assigned by the SMF, for example, the N6 interface IP address may be assigned by the SMF.

For the bearer network, when the router forwards the packet, the router may determine the UPF corresponding to the packet according to the IP address of the packet, and send the packet to the determined UPF.

When the disaster tolerance UPF replaces the main UPF to receive, process and forward the message, the disaster tolerance UPF can adopt the same forwarding plane IP address as the main UPF facing the router, so that the router sends the message originally sent to the main UPF to the disaster tolerance UPF, thereby realizing that the disaster tolerance UPF replaces the main UPF to forward the message of the PDU session.

In some embodiments, the disaster tolerance UPF may send, to the router, first routing indication information after the primary UPF has a forwarding plane failure, where the first routing indication information includes an IP address of a forwarding plane of the primary UPF, so that the router sends, according to the IP address of the forwarding plane, a packet in the PDU session to the disaster tolerance UPF. For example, when a in fig. 8 indicates that the master UPF works normally, the route instruction information is sent to a router (not shown in the figure) in the bearer network, and the route instruction information may include its N3 address, N6 address, N9 address, N4 address, etc.; and after receiving the message from the RAN, the router in the bearer network sends the message to the main UPF according to the IP address in the message. B in fig. 8 indicates that the forwarding plane of the main UPF has failed, and after determining that the forwarding plane of the main UPF has failed through heartbeat detection, the disaster tolerance UPF sends first routing indication information to the router in the bearer network, where the first routing indication information includes the forwarding plane IP address of the main UPF (e.g., the N3 interface IP address, the N6 interface IP address, etc.) so as to indicate the router to send the message that should be originally sent to the main UPF to the disaster tolerance UPF.

In some other embodiments, the disaster recovery UPF may send, to the router, the second routing indication information after acquiring the IP address of the forwarding plane of the primary UPF, where the second routing indication information includes the IP address and the priority indication information of the forwarding plane of the primary UPF. Wherein, the priority indication information is used for indicating the route priority of the disaster tolerance UPF for the IP address of the forwarding plane; and the routing priority of the IP address disaster tolerance UPF of the forwarding plane is lower than that of the main UPF. Correspondingly, when the main UPF sends the routing indication information to the router, the main UPF needs to carry priority indication information in addition to its own forwarding plane IP address, so as to indicate that the routing priority of the main UPF for the forwarding plane IP address is higher than that of the disaster tolerance UPF.

Although the master UPF and the disaster recovery UPF use the same IP address in the PDU session, the router obtains the routing priority information corresponding to the master UPF and the disaster recovery UPF, so that when the master UPF is normal, the router preferentially sends the message with the target IP address as the IP address to the master UPF, and when the router determines that the forwarding plane of the master UPF fails, the router can send the message with the target IP address as the IP address to the disaster recovery UPF. Optionally, the router may also determine whether the forwarding plane failure occurs in the main UPF through heartbeat detection. For example, the router may periodically generate a heartbeat detection request to the master UPF, and if a heartbeat detection response returned by the master UPF can be received, the master UPF is considered to be normal on the forwarding plane, and if the heartbeat detection response cannot be normally received, the master UPF is considered to have a forwarding plane failure.

In order to facilitate IP management for the UPF, the set of IP resources may also be divided in advance. An IP resource group includes each bearer IP (such as N3 interface IP address, N6 interface IP address, N9 interface IP address) or each IP address field on each interface of the PDU session on the forwarding plane. For example, the N3 interface IP address, the N6 interface IP address, and the N9 interface IP address of UPF1 are IP resource group 1, the N3 interface IP address, the N6 interface IP address, and the N9 interface IP address of UPF2 are IP resource group 2. For another example, the IP addresses 1 to M of the N3 interface to N, N interface may be set as IP resource group 1, and the bearer IPs of the forwarding plane belong to the same IP resource group for one PDU session.

Assuming that the master UPF uses the IP resource group 1, the disaster recovery UPF can send first routing indication information to the router after the master UPF has a forwarding plane fault, wherein the first indication information comprises each IP address of the IP resource group 1; the disaster tolerance UPF may also send first second routing indication information to the router, where the second routing indication information includes priority information and each IP address of the IP resource group 1, so that the router determines that, for the IP resource group 1, the routing priority of the disaster tolerance UPF is lower than the routing priority of the master UPF.

In the 1+1 master/slave mode, the master UPF and the disaster recovery UPF share one IP resource group, but the disaster recovery UPF uses the IP resource group only when the master UPF fails on the forwarding plane. As shown in fig. 9, the UPF1 is a main UPF, and the IP resource group 1 is used to receive and forward messages, and the UPF2 is a disaster recovery UPF; the UPF1 sends the context information of the PDU conversation carried by the UPF1 to the UPF2, namely the UPF2 obtains the IP resource group 1; if the UPF1 has a forwarding plane fault, the UPF2 receives and forwards the message of the PDU session originally borne by the UPF1 by adopting the IP resource group 1.

In the 1+1 mutual assistance mode, the UPF1 and the UPF2 are disaster recovery UPFs. In the embodiment shown in fig. 10, UPF1 is the master UPF with resource set 1 IP and UPF2 is the master UPF with resource set 2 IP. Because the UPF1 and the UPF2 are disaster tolerant UPFs, if the forwarding plane of the UPF1 fails, the UPF2, which is originally a service message carried by the master UPF, still receives and forwards the service message through the IP resource group 2, and meanwhile, the UPF2 receives and forwards a message of the PDU session originally carried by the UPF1 by using the IP resource group 1.

In the above N +1 mode, N primary UPFs may correspond to N IP resource groups, and one disaster recovery UPF may obtain the N IP resource groups, respectively, so that after a failure occurs on a forwarding plane of any one or more of the N primary UPFs, the disaster recovery UPF may receive and forward a message using the corresponding IP resource group. In the specific embodiment shown in fig. 11, when the UPF1 is the master UPF, the IP resource group 1 is used, and when the UPF2 is the master UPF, the IP resource group 2 is used, and when the UPF3 is the master UPF, the IP resource group 3, … is used; the UPF100 is a disaster recovery UPF of UPF1, UPF2, UPF3 …. The UPF1, the UPF2 and the UPF3 … respectively send the context information of the PDU session carried by the UPF1, the UPF2 and the UPF3 … to the UPF100, that is, the UPF100 acquires the IP resource group 1, the IP resource group 2 and the IP resource group 3 …. If the forwarding plane of the UPF2 fails, the UPF100 may receive and forward the PDU session message originally borne by the UPF2 by using the IP resource group 2; similarly, if the forwarding plane of another UPF fails, the UPF100 receives and forwards the PDU session packet carried by the UPF by using the corresponding IP resource group.

In the above-mentioned N way pool mutual-aid mode, the configuration manner of the IP resource group may be as shown in fig. 12. For the first part of PDU session, UPF1 is used as main UPF, and IP resource group 1 is adopted; and the UPF2 is used as a disaster tolerance UPF, and the UPF1 sends the context information of the first part of PDU session to the UPF2, namely the UPF2 acquires the IP resource group 1. For the second part of PDU session, UPF1 is used as the main UPF, and IP resource group 2 is adopted; and the UPF3 is used as a disaster tolerance UPF, and the UPF1 sends the context information of the second part of PDU session to the UPF3, namely the UPF3 acquires the IP resource group 2. For the third part of PDU session, UPF2 is used as the main UPF, and IP resource group 3 is adopted; and the UPF3 is used as a disaster tolerance UPF, and the UPF2 sends the context information of the third part of PDU session to the UPF3, namely the UPF3 acquires the IP resource group 3. For the fourth part PDU session, UPF2 is used as the main UPF, and an IP resource group 4 is adopted; and the UPF1 is used as a disaster tolerance UPF, and the UPF2 sends the context information of the PDU session of the fourth part to the UPF1, namely the UPF1 acquires the IP resource group 4. For the fifth part of PDU session, UPF3 is used as the main UPF, and IP resource group 5 is adopted; and the UPF1 is used as a disaster tolerance UPF, and the UPF3 sends the context information of the fifth part of PDU session to the UPF1, namely the UPF1 acquires the IP resource group 5. For the sixth part of PDU conversation, UPF3 is used as the main UPF, and an IP resource group 6 is adopted; and the UPF2 is used as a disaster tolerance UPF, and the UPF3 sends the context information of the sixth part of PDU session to the UPF2, namely the UPF2 acquires the IP resource group 6. When the UPF2 has a forwarding plane failure, the UPF1 still adopts the IP resource group 1 to receive and forward the messages of the first part of PDU sessions, and still adopts the IP resource group 2 to receive and forward the messages of the second part of PDU sessions; the UPF3 still adopts the IP resource group 5 to receive and forward the messages of the fifth part of PDU conversation, and still adopts the IP resource group 6 to receive and forward the messages of the sixth part of PDU conversation; meanwhile, the UPF1 receives and forwards the message of the fourth part of PDU session by adopting the IP resource group 4, and the UPF3 receives and forwards the message of the third part of PDU session by adopting the IP resource group 3.

Further, if the N6 interface IP address of the UPF is allocated by the SMF, the SMF may further send an identifier of the IP resource group, so that the UPF determines the corresponding N3 interface IP address and other addresses according to the identifier of the IP resource group. For example, in the specific embodiment shown in fig. 13, the SMF sends a PFCP session establishment request to the UPF1 (master UPF), where the request includes the N6 interface IP address allocated by the SMF to the UPF1 and the identifier of the IP resource group, and the UPF1 replies a PFCP session establishment response to the SMF, where the response includes the N3 interface IP address allocated by the UPF1 to the IP resource group, and the N3 interface IP address allocated by the UPF1 needs to ensure that the PFCP session establishment request and the N6 interface IP address belong to the same IP resource group. The SMF sends a PFCP session establishment request to a UPF2 (disaster tolerance UPF), wherein the request comprises the IP address of the N6 interface and the IP address of the N3 interface, so that the UPF2 obtains the IP address of a forwarding plane of the IP resource group; UPF2 replies a PFCP session setup response to the SMF. If the PFCP session establishment request sent by the SMF to the UPF1 (master UPF) includes an N6 interface IP address but does not include an identifier of an IP resource group, the UPF1 may determine, according to information of a preconfigured IP resource group, an IP to which the N6 interface IP address belongs, and further determine an N3 interface IP address in the IP resource group.

And if the IP address of the N3 interface and the IP address of the N6 interface are both determined by the master UPF, the master UPF determines the IP address of the N3 interface and the IP address of the N6 interface which belong to the same IP resource group, carries the IP addresses in the PFCP session establishment response and sends the response to the SMF. Then, the SMF sends the IP address of the N3 interface and the IP address of the N6 interface which belong to the same IP resource group and are determined by the main UPF to the disaster recovery UPF through a PFCP session establishment request; or the main UPF directly sends the N3 interface IP address and the N6 interface IP address which belong to the same IP resource group and are determined by the main UPF to the disaster recovery UPF through a request or a notification message; or, the master UPF may send the N3 interface IP address and the N6 interface IP address belonging to the same IP resource group determined by the master UPF to the disaster recovery UPF in a data synchronization manner between the DBs.

As previously described, the UPF includes a forwarding plane and a control plane. In the control plane, optionally, the disaster tolerance UPF may also use the same IP address as the main UPF, for example, the disaster tolerance UPF and the main UPF use the same N4 interface IP address, so that the disaster tolerance UPF can receive the control information that is sent by the SMF and originally should be received by the main UPF. For example, after determining that the forwarding plane of the main UPF fails, the disaster tolerant UPF sends the first routing indication information to the router in the bearer network, where the first routing indication information may further include an N4 interface IP address of the main UPF, so that the router sends the control information, which is originally sent by the SMF to the main UPF, to the disaster tolerant UPF. In this implementation, the failover of the UPF is invisible to the SMF, i.e., the SMF does not have to know that the primary UPF failed and is taken over by the disaster tolerant UPF. Alternatively, the interface IP address in the control plane may not be sent together with the first routing indication information. Or, after acquiring the N4 interface IP address of the main UPF, the disaster recovery UPF may send routing indication information to the router, where the indication information includes the N4 interface IP address of the main UPF and priority indication information.

Optionally, the failure switching of the UPF may also be visible to the SMF, that is, the SMF may know the existence of the disaster tolerance UPF, and when the main UPF fails, the SMF sends control information to the disaster tolerance UPF. In a specific embodiment, as shown in fig. 14, the SMF, the primary UPF, and the disaster tolerance UPF may send a PFCP session establishment request to the primary UPF, and the primary UPF replies a PFCP session establishment response to the SMF, where the response includes an N4 interface IP address of the primary UPF and an N4 interface IP address of the disaster tolerance UPF. When the primary UPF is normal, the SMF sends a PFCP session modification request to the primary UPF, and the primary UPF replies a PFCP session modification response to the SMF. After the main UPF fails (forwarding plane failure and/or control plane failure), if the relevant information of the PFCP session changes, the SMF sends a PFCP session modification request to the disaster recovery UPF, and the disaster recovery UPF replies a PFCP session modification response to the SMF.

In some embodiments, if the main UPF only has a control plane failure but the forwarding plane is normal, the disaster recovery UPF may also take over the main UPF to work only on the control plane, and the main UPF still forwards the packet on the forwarding plane. For example, in the embodiment shown in fig. 15, for the PDU session of UE1, UPF1 is as the primary UPF, and UPF2 is as the disaster tolerance UPF; for the PDU session of UE2, UPF2 is as the master UPF and UPF1 is as the disaster tolerance UPF. And the link between the UPF1 and the SMF is failed, so that the UPF1 can not normally communicate with the SMF, the SMF sends the updated context information of the PDU session of the UE1 to the UPF2, and the UPF2 sends the updated context information of the PDU session of the UE1 to the UPF1 through the session modification request, so that the UPF1 can continuously forward and process the message of the PDU session of the UE 1.

In the embodiment shown in fig. 15, a service processing module (not shown in the figure) in the UPF2 may send the received updated PDU session context information of the UE1 to a DB in the UPF2, and then the DB in the UPF2 sends the updated PDU session context information of the UE1 to the DB in the UPF1, and the DB in the UPF1 sends the updated context information to the service processing module (not shown in the figure) in the UPF 1.

Further, the updated PDU session context information of UE1, UPF2, may also be sent to UPF1 through a request and notification message between UPFs, as shown in fig. 16. For example, the service processing module (not shown in the figure) of the UPF2 may send the updated PDU session context information of the UE1 to the service processing module (not shown in the figure) of the UPF1 through the session modification request. Further, the service processing module of the UPF1 sends the updated context information to the DB of the UPF1, the DB of the UPF1 sends the updated context information to the DB of the UPF2, and the DB of the UPF2 sends the updated context information to the service processing module of the UPF2, so that the UPF2 can forward the packet of the PDU session according to the updated PDU session context information of the UE1 after the forwarding plane failure occurs in the UPF 1.

Fig. 17 is a schematic diagram of a communication device according to an embodiment of the present application. The communication device includes a processing module 1701 and a transceiver module 1702. The processing module 1701 is used to implement the processing of data by the communication device. The transceiving module 1702 is configured to perform the information transceiving process in the foregoing method embodiments. It is to be understood that the processing module 1701 in the embodiments of the present application may be implemented by a processor or a processor-related circuit component (or, alternatively, referred to as a processing circuit), and the transceiving module 1702 may be implemented by a receiver or a receiver-related circuit component, a transmitter or a transmitter-related circuit component.

The communication device may be a communication device apparatus, or may be a chip applied to the communication device apparatus, or other combined device, component, and the like having the functions of the communication device apparatus.

For example, the communication device may be a disaster tolerance UPF in the foregoing method embodiment, may also be a master UPF in the foregoing method embodiment, and may also be an SMF in the foregoing method embodiment.

When the communication device is a disaster tolerance UPF, the transceiver module 1702 may be configured to perform information transceiving processing in the foregoing method embodiment, for example, receive first indication information, forward a packet of the PDU session, and the like, and the processing module 1701 is configured to control the transceiver module 1702 to perform transceiving operation, and the like.

In addition, the above components may also be used to support other processes performed by the disaster tolerance UPF in the above method embodiment. The beneficial effects can be obtained by referring to the foregoing description, and are not described in detail herein.

When the communication device is a master UPF, the processing module 1701 is configured to perform processing functions in the above method embodiments, such as determining context information of a PDU session; the transceiving module 1702 is configured to perform the information transceiving process in the foregoing method embodiment, for example, send the first indication information to the disaster tolerance UPF of the PDU session.

In addition, the various components described above may also be used to support other processes performed by the master UPF in the method embodiments described above. The beneficial effects can be obtained by referring to the foregoing description, and are not described in detail herein.

When the communication apparatus is an SMF, the processing module 1701 is configured to perform processing functions in the foregoing method embodiments, for example, operations such as determining context information of a PDU session; the transceiving module 1702 is configured to perform transceiving operations in the foregoing method embodiments, for example, send a first session establishment request to the disaster recovery UPF of the PDU session.

In addition, the above components may also be used to support other processes performed by the SMF in the above method embodiments. The beneficial effects can be obtained by referring to the foregoing description, and are not described in detail herein.

Based on the same technical concept, the embodiment of the present application further provides a communication device, which includes a processor 1801 as shown in fig. 18, and a communication interface 1802 connected to the processor 1801.

The processor 1801 may be a general purpose processor, a microprocessor, an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other programmable logic device, discrete gate or transistor logic, or one or more integrated circuits for controlling the execution of programs in accordance with the teachings of the present application, among others. A general purpose processor may be a microprocessor or any conventional processor or the like. The steps of a method disclosed in connection with the embodiments of the present application may be directly implemented by a hardware processor, or may be implemented by a combination of hardware and software modules in a processor.

Communication interface 1802 may employ any transceiver or the like for communicating with other devices or communication networks, such as an ethernet, RAN, wireless Local Area Networks (WLANs), and the like.

In this embodiment of the present application, the processor 1801 is configured to invoke the communication interface 1802 to perform a receiving and/or transmitting function, and to perform the user plane function disaster recovery method according to any one of the foregoing possible implementation manners.

Further, the communication device may also include a memory 1803 and a communication bus 1804.

The memory 1803 is used for storing program instructions and/or data, so that the processor 1801 can call the instructions and/or data stored in the memory 1803 to implement the above functions of the processor 1801. The memory 1803 may be, but is not limited to, a read-only memory (ROM) or other type of static storage device that may store static information and instructions, a Random Access Memory (RAM) or other type of dynamic storage device that may store information and instructions, an electrically erasable programmable read-only memory (EEPROM) 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. The memory 1803, which may be separate and distinct, may be coupled to the processor 1801 via the communication bus 1804. The memory 1803 may also be integrated with the processor 1801.

The communication bus 1804 may include a path that carries information between the aforementioned components.

For example, the communication device may be a disaster recovery UPF in the above method embodiment, may also be a main UPF in the above method embodiment, and may also be an SMF in the above method embodiment.

The processor 1801 is configured to implement data processing operations of the communication device, and the communication interface 1802 is configured to implement receiving operations and transmitting operations of the communication device.

When the communication device is a disaster tolerance UPF, the communication interface 1802 is configured to receive first indication information, where the first indication information includes context information of a PDU session, and the context information includes a forwarding plane IP address of a master UPF of the PDU session. The processor 1801 is configured to forward, through the communication interface 1802, a packet of the PDU session according to a forwarding plane IP address of the master UPF when the master UPF has a forwarding plane failure.

In addition, the above components may also be used to support other processes performed by the disaster recovery UPF in the above method embodiment. The beneficial effects can be referred to the previous description, and are not described in detail herein.

When the communication device is a master UPF, the processor 1801 is configured to determine context information of a PDU session, where the context information of the PDU session includes a forwarding plane IP address of the master UPF; and sending first indication information to the disaster tolerance UPF of the PDU session through a communication interface 1802, wherein the first indication information comprises the context information of the PDU session.

In addition, the above components may also be used to support other processes performed by the master UPF in the above method embodiments. The beneficial effects can be referred to the previous description, and are not described in detail herein.

When the communication device is an SMF, the processor 1801 is configured to determine context information of a PDU session, where the context information includes a forwarding plane IP address of a primary UPF of the PDU session; and sending a first session establishment request to the disaster recovery UPF of the PDU session through a communication interface 1802, wherein the first session establishment request comprises the context information of the PDU session.

In addition, the above components may also be used to support other processes performed by the SMF in the above method embodiments. The beneficial effects can be obtained by referring to the foregoing description, and are not described in detail herein.

The embodiment of the application provides a computer readable storage medium, which stores a computer program, wherein the computer program comprises instructions for executing the method embodiment.

Embodiments of the present application provide a computer program product comprising instructions which, when run on a computer, cause the above-described method embodiments to be performed.

In the description of the embodiment of the present application, "and/or" describes an association relationship of associated objects, which means that three relationships may exist, for example, a and/or B may mean: a exists alone, A and B exist simultaneously, and B exists alone. The plural in the present application means two or more.

In addition, it is to be understood that the terms first, second, third and the like in the description of the present application are used for distinguishing between the descriptions and are not to be construed as indicating or implying relative importance or order. Reference throughout this specification to "one embodiment" or "some embodiments," or the like, means that a particular feature, structure, or characteristic described in connection with the embodiment is included in one or more embodiments of the present application. Thus, appearances of the phrases "in one embodiment," "in some embodiments," "in other embodiments," or the like, in various places throughout this specification are not necessarily all referring to the same embodiment, but rather "one or more but not all embodiments" unless specifically stated otherwise. The terms "comprising," "including," "having," and variations thereof mean "including, but not limited to," unless expressly specified otherwise.

The embodiment of the application provides a computer readable storage medium, which stores a computer program, wherein the computer program comprises instructions for executing the method embodiment.

Embodiments of the present application provide a computer program product comprising instructions which, when run on a computer, cause the computer to perform the above-described method embodiments.

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

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

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

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

While the preferred embodiments of the present application have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all alterations and modifications as fall within the scope of the application.

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

Claims (26)

1. A UPF disaster recovery method is characterized by comprising the following steps:

receiving first indication information by a disaster tolerance UPF, wherein the first indication information comprises context information of a PDU session of a packet data unit, and the context information comprises an IP address of a forwarding plane of a main UPF of the PDU session;

and when the forwarding plane of the main UPF fails, the disaster tolerance UPF forwards the message of the PDU session according to the IP address of the forwarding plane of the main UPF.

2. The method according to claim 1, wherein the disaster recovery UPF receives the first indication information, and comprises:

the disaster tolerance UPF receives first indication information sent by a master UPF of the PDU session; or

And the disaster tolerance UPF receives first indication information sent by a session management function SMF.

3. The method according to claim 2, wherein the receiving, by the disaster recovery UPF, the first indication information sent by the master UPF of the PDU session includes:

the disaster tolerance UPF receives a session establishment request sent by a master UPF of the PDU session, wherein the session establishment request comprises the first indication information; or

And the disaster tolerance UPF receives a session modification request sent by a master UPF of the PDU session, wherein the session modification request comprises the first indication information.

4. The method according to claim 2, wherein the receiving, by the disaster recovery UPF, the first indication information sent by the master UPF of the PDU session includes:

and the database DB in the disaster tolerance UPF receives first indication information sent by the DB in the master UPF of the PDU conversation.

5. The method according to any of claims 1-4, wherein the context information of the PDU session is the basic service context information of the PDU session;

when a failure of a forwarding plane occurs in a primary UPF of the PDU session, the method further comprises:

the disaster tolerance UPF receives second indication information sent by the SMF, wherein the second indication information comprises value added service context information of the PDU session;

and the disaster tolerance UPF performs service processing on the message of the PDU session according to the value added service context information.

6. The method according to any of claims 1-5, wherein after a forwarding plane failure of a primary UPF of the PDU session, the method further comprises:

and the disaster tolerance UPF sends first routing indication information to a router, wherein the first routing information comprises a forwarding plane IP address of the main UPF, so that the router forwards the message in the PDU session to the disaster tolerance UPF according to the forwarding plane IP address.

7. The method according to any one of claims 1-5, further comprising:

the disaster tolerance UPF sends second routing indication information to a router, wherein the second routing indication information comprises a forwarding plane IP address of the main UPF and priority indication information, and the priority indication information is used for indicating the routing priority of the disaster tolerance UPF for the forwarding plane IP address; and for the IP address of the forwarding plane, the routing priority of the disaster recovery UPF is lower than that of the main UPF.

8. The method of any of claims 1-7, wherein the forwarding plane IP address comprises:

the IP addresses of the UPF and wireless access network interfaces, and the IP addresses of the UPF and data network interfaces; or

The IP addresses of the UPF and the wireless access network interface and the IP addresses of the UPF and the UPF interface; or alternatively

The IP addresses of the UPF and UPF interfaces, and the IP addresses of the UPF and data network interfaces.

9. The method according to any of claims 6-8, wherein the routing indication information further includes an IP address of the primary UPF and SMF interface, so that the router forwards control plane information sent by the SMF according to the control plane IP address.

10. The method according to any one of claims 1-9, further comprising:

when a link between a main UPF and an SMF of the PDU session fails and a forwarding plane is normal, the disaster recovery UPF receives control plane information of the PDU session sent by the SMF, wherein the control plane information comprises context information after the PDU session is updated;

and the disaster tolerance UPF sends the updated context information to a master UPF of the PDU conversation.

11. A UPF disaster recovery method is characterized by comprising the following steps:

a master UPF determines context information of a Packet Data Unit (PDU) session, wherein the context information of the PDU session comprises a forwarding plane IP address of the master UPF;

and the master UPF sends first indication information to the disaster tolerance UPF of the PDU conversation, wherein the first indication information comprises the context information of the PDU conversation.

12. The method according to claim 11, wherein the sending, by the master UPF, first indication information to the disaster tolerant UPF of the PDU session comprises:

a session establishment request sent by the master UPF to the disaster recovery UPF, wherein the session establishment request comprises the first indication information; or alternatively

And the session modification request is sent to the disaster recovery UPF by the main UPF and comprises the first indication information.

13. The method according to claim 11, wherein the master UPF sends a first indication to the disaster tolerant UPF of the PDU session, comprising:

and the database DB in the main UPF sends the first indication information to the DB in the disaster tolerance UPF.

14. The method according to any of claims 11-13, wherein the context information of the PDU session is basic service context information of the PDU session, and the basic service context information is necessary context information when forwarding packets in the PDU session.

15. The method according to any one of claims 11-14, further comprising:

the main UPF receives a session establishment request sent by the SMF, wherein the request comprises a UPF and data network interface IP address and an IP resource group identifier;

and the main UPF sends a session establishment response to the SMF according to the session establishment request, wherein the response comprises UPF and wireless access network interface IP addresses, and the UPF and the wireless access network interface IP addresses belong to the IP resource group corresponding to the IP resource group identifier.

16. The method according to any one of claims 11-15, further comprising:

the main UPF sends first routing indication information to a router, wherein the first routing indication information comprises a forwarding plane IP address of the main UPF and priority indication information, the priority indication information is used for indicating the routing priority of the main UPF for the forwarding plane IP address, the routing priority of the main UPF for the forwarding plane IP address is higher than that of the disaster tolerance UPF, and the first routing indication information is used for indicating the router to forward a message according to the forwarding plane IP address and the priority indication information.

17. The method according to any one of claims 11-16, further comprising:

when the link between the main UPF and the SMF is failed and the forwarding plane is normal, the main UPF receives the updated context information of the PDU session sent by the disaster recovery UPF;

and the master UPF processes the message in the PDU conversation according to the updated context information.

18. The method according to claim 17, wherein the receiving, by the master UPF, the PDU session updated context information sent by the disaster recovery UPF includes:

and the DB in the main UPF receives the context information after the PDU session is updated, which is sent by the DB in the disaster tolerance UPF.

19. A UPF disaster recovery method is characterized by comprising the following steps:

a Session Management Function (SMF) determines context information of a Packet Data Unit (PDU) session, wherein the context information comprises a forwarding plane IP address of a main UPF of the PDU session;

and the SMF sends a first session establishment request to the disaster tolerance UPF of the PDU session, wherein the first session establishment request comprises the context information of the PDU session.

20. The method of claim 19, wherein prior to the SMF determining context information for a PDU session, the method further comprises:

the SMF sends a second session establishment request to a master UPF of the PDU session;

and the SMF receives a second session establishment response sent by the main UPF, wherein the second session establishment response comprises the forwarding plane IP address of the main UPF.

21. The method of claim 20, wherein the second session establishment request includes an IP address and an IP resource group identification of a UPF and data network interface assigned to the master UPF;

and the forwarding surface IP address in the second session establishment response belongs to the IP resource group corresponding to the IP resource group identifier.

22. The method according to any of claims 19-21, wherein when the primary UPF experiences a control plane failure, the method further comprises:

and the SMF sends the control information of the PDU session to the disaster tolerance UPF.

23. A communications apparatus, comprising: a processor, and a memory and a communication interface respectively coupled to the processor; the communication interface is used for communicating with other equipment; the processor, for executing instructions or programs in the memory, to perform the method of any of claims 1-10 via the communication interface.

24. A communications apparatus, comprising: a processor, and a memory and a communication interface respectively coupled to the processor; the communication interface is used for communicating with other equipment; the processor, for executing instructions or programs in the memory, to perform the method of any of claims 11-18 through the communication interface.

25. A communications apparatus, comprising: a processor, and a memory and a communication interface respectively coupled to the processor; the communication interface is used for communicating with other equipment; the processor, for executing instructions or programs in the memory, to perform the method of any of claims 19-22 via the communication interface.

26. A computer-readable storage medium having stored therein instructions which, when executed on a computer, cause the computer to perform the method of any one of claims 1-22.

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