Communication method, device and system
By deploying H-UPF at the access point and managing sessions in the home network, the problem of roaming data offloading being detrimental to control and management in existing technologies is solved, thereby achieving continuity of roaming services and enhanced data control and management.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-26
- Publication Date
- 2026-03-27
AI Technical Summary
In existing technologies, data offloading in roaming scenarios is achieved solely through the Access User Plane Function (V-UPF), which is not conducive to the home network's control and management of roaming data, and especially cannot guarantee service continuity in the event of a failure.
By deploying Home User Plane Function (H-UPF) at the access location, the session management function network element in the home network can detect H-UPF failures, release the original session and establish a new H-UPF session, update the session context information to achieve data offloading, enhance the control and management of the home network and ensure service continuity.
It enables the offloading of roaming data through H-UPF, enhances the home network's control and management of roaming data, such as billing management and QoS flow management, and ensures the continuity of roaming services in the event of H-UPF failure.
Smart Images
Figure CN121751391A_ABST
Abstract
Description
Technical Field
[0001] This disclosure relates to the field of mobile communication technology, and in particular to a communication method, apparatus and system. Background Technology
[0002] Roaming scenarios are mainly divided into two types: Local Breakout and Home Routed (HR). Currently, these two scenarios only support the deployment of Home User Plane Function (H-UPF) on the Home Public Land Mobile Network (HPLMN).
[0003] In related technologies, for home-routed roaming scenarios, 5G systems support the HR-SBO (Home-Routed Session Breakout) mechanism, which offloads data through the Visited Public Land Mobile Network (VPLMN) User Plane Function (V-UPF). However, offloading data through V-UPF is not conducive to HPLMN's control and management of roaming data (such as billing management). Summary of the Invention
[0004] This disclosure provides a communication method, apparatus, and system.
[0005] According to a first aspect of this disclosure, a communication method is provided, comprising: detecting a fault in a first user plane function element in the home network, wherein the first user plane function element is deployed in the access location; releasing a first Home Routing Protocol Data Unit (HR PDU) session established for a user equipment via the first user plane function element; and establishing a second HR PDU session for the user equipment via a second user plane function element in the home network, wherein the second user plane function element is deployed in the home location.
[0006] In some embodiments, establishing a second HR PDU session via a second user plane function element in the home network includes: selecting the second user plane function element; sending a session request to the second user plane function element; and receiving a session response from the second user plane function element.
[0007] In some embodiments, establishing a second HR PDU session via a second user plane function element in the home network further includes updating locally stored session context information.
[0008] In some embodiments, updating the locally stored session context information includes: updating the information of the Domain Name System (DNS) server corresponding to the first HR PDU session to the information of the DNS server corresponding to the second HR PDU session, wherein the DNS server corresponding to the first HR PDU session is deployed in the access location and the DNS server corresponding to the second HR PDU session is deployed in the home location; and / or updating the user plane path information corresponding to the first HR PDU session to the user plane path information corresponding to the second HR PDU session.
[0009] In some embodiments, selecting the second user plane function network element includes: when there are no other user plane function network elements belonging to the home network other than the first user plane function network element in the access location, or when there are other user plane function network elements in the access location but the other user plane function network elements do not meet the set selection conditions, selecting the second user plane function network element from the user plane function network elements deployed in the home location that belong to the home network.
[0010] In some embodiments, the communication method further includes: establishing a third HR PDU session for the user equipment via the network element that meets the selection criteria when there is a network element that meets the selection criteria among the other user plane function network elements.
[0011] In some embodiments, updating the user plane path information corresponding to the first HR PDU session to the user plane path information corresponding to the second HR PDU session includes: updating the uplink splitter information and PDU session anchor information corresponding to the first HR PDU session to the uplink splitter information and PDU session anchor information corresponding to the second HR PDU session.
[0012] In some embodiments, the first user plane function network element supports uplink splitter functionality and PDU session anchor functionality established for the first HR PDU session.
[0013] In some embodiments, the step of knowing that a first user plane function element in the home network is faulty includes: receiving a fault report from the first user plane function element; and determining that the first user plane function element is faulty based on the fault report.
[0014] In some embodiments, the fault report carries an identifier of the accessed network.
[0015] According to a second aspect of this disclosure, a communication apparatus is provided, disposed in a session management function network element in a home network, comprising: a detection module configured to detect a fault in a first user plane function network element in the home network, wherein the first user plane function network element is deployed at the access location; a session release module configured to release a first Home Routing Protocol Data Unit (HR PDU) session established for a user equipment via the first user plane function network element; and a session establishment module configured to establish a second HR PDU session for the user equipment via a second user plane function network element in the home network, wherein the second user plane function element is deployed at the home location.
[0016] According to a third aspect of this disclosure, a communication device is provided, comprising: a memory; and a processor coupled to the memory, the processor being configured to perform the communication method as described above based on instructions stored in the memory.
[0017] According to a fourth aspect of this disclosure, a communication system is provided, comprising: a session management function network element in a home network, including the communication device as described above; a first user plane function network element configured to assist the session management function network element in releasing a first HR PDU session; and a second user plane function network element configured to assist the session management function network element in establishing a second HR PDU session.
[0018] According to a fifth aspect of this disclosure, a computer-readable storage medium is provided that stores computer program instructions thereon, which, when executed by a processor, implement the communication method as described above.
[0019] According to a sixth aspect of this disclosure, a computer program product is provided having computer program instructions stored thereon, which, when executed by a processor, implement the communication method as described above.
[0020] Other features and advantages of this disclosure will become clear from the following detailed description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description
[0021] The accompanying drawings, which form part of this specification, illustrate embodiments of this disclosure and, together with the specification, serve to explain the principles of this disclosure.
[0022] Figure 1 This is a schematic diagram of the system architecture in a roaming scenario according to some embodiments of this disclosure;
[0023] Figure 2 This is a flowchart illustrating a communication method according to some embodiments of the present disclosure;
[0024] Figure 3This is a flowchart illustrating a communication method according to other embodiments of this disclosure;
[0025] Figure 4 This is a schematic diagram of the structure of a communication device according to some embodiments of the present disclosure;
[0026] Figure 5 This is a schematic diagram of the structure of a communication device according to other embodiments of the present disclosure;
[0027] Figure 6 This is a schematic diagram of the structure of a communication system according to some embodiments of the present disclosure.
[0028] This disclosure can be more clearly understood with reference to the accompanying drawings and the following detailed description. Detailed Implementation
[0029] Various exemplary embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values of the components and steps set forth in these embodiments do not limit the scope of the present disclosure.
[0030] At the same time, it should be understood that, for ease of description, the dimensions of the various parts shown in the accompanying drawings are not drawn according to actual scale.
[0031] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit this disclosure or its application or use.
[0032] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.
[0033] In all examples shown and discussed herein, any specific values should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.
[0034] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.
[0035] To make the objectives, technical solutions, and advantages of this disclosure clearer, the following detailed description is provided in conjunction with specific embodiments and the accompanying drawings.
[0036] In related technologies, using V-UPF to offload roaming data is not conducive to the home network's control and management of roaming data. The inventors of this disclosure have discovered that the current limitation of using V-UPF to offload roaming data in roaming scenarios is due to the fact that current communication systems only support deploying H-UPF at the home location.
[0037] In view of this, this disclosure proposes a new communication method, apparatus and system that can support the offloading of roaming data through H-UPF and ensure service continuity in the event of H-UPF failure.
[0038] Figure 1 This is a schematic diagram of the system architecture in a roaming scenario according to some embodiments of this disclosure. For example... Figure 1 As shown, the system architecture of this disclosure embodiment includes a Visited Public Land Mobile Network (VPLMN) and a Home Public Land Mobile Network (HPLMN).
[0039] VPLMN includes functions such as User Equipment (UE), Radio Access Network (RAN), Access and Mobility Management Function (AMF), User Plane Function (UPF), and Session Management Function (SMF). HPPLMN includes functions such as SMF and UPF. To distinguish the functions in the two networks, the prefix "H" or "V" is used. For example, the user plane function in VPLMN is called V-UPF, and the user plane function in HPPLMN is called H-UPF.
[0040] The main difference between the system architecture in this disclosure and related technologies lies in the deployment of H-UPF at the access location. For example, H-UPF can be deployed at the access location via cloud technology.
[0041] In HR roaming scenarios, a first Home Routed Protocol Data Unit (HR PDU) session is established for a UE moving to the access location via the V-UPF and the H-UPF located at the access location. The H-UPF deployed at the access location can include two types of UPFs: a PDU Session Anchor (PSA) and an Uplink Classifier (UL CL). In practice, the PSA and UL CL functions can be configured on different devices or on the same device (e.g., the same network element). The data flow carried by the first HR PDU session can be sent from the UE to the V-UPF, then from the V-UPF to the H-UPF (which acts as the ULCL), then from the H-UPF (which acts as the ULCL) to the H-UPF (which acts as the PSA), and finally from the H-UPF (which acts as the PSA) to the data network.
[0042] Figure 2 This is a flowchart illustrating a communication method according to some embodiments of the present disclosure. Figure 2 As shown, the communication method includes steps S21 to S23.
[0043] In step S21, it is learned that the first user plane function element in the home network is faulty.
[0044] In some embodiments of this disclosure, the communication method can be executed by a session management function network element in the home network. This session management function network element in the home network can be, for example, an H-SMF network element.
[0045] The first user plane functional network element is deployed at the access location. For example, the first user plane functional network element can be an H-UPF network element deployed at the access location. For example, the first user plane functional network element can be a network element supporting PSA function deployed at the access location, or it can be an H-UPF network element supporting both PSA function and ULCL function.
[0046] The session management function network element in the home network can determine whether the first user plane function network element has failed in several ways. Two such determination methods are given below as examples.
[0047] In the first determination method, the session management function network element in the home network receives a fault report from the first user plane function network element and determines that the first user plane function network element is faulty based on the fault report.
[0048] In some examples, the fault report carries the identifier of the accessed network. For example, the identifier of the accessed network may be the identifier of the VPLMN. After receiving the fault report, the session management function network element in the home network can determine which H-UPF network element in which the fault occurred based on the identifier of the accessed network.
[0049] In other examples, the fault report carries the identifier of the accessed network and the identifier of the first user plane function (H-UPF) network element. Upon receiving the fault report, the session management function (SMF) network element in the home network can accurately determine which accessed network and which H-UPF network element experienced the fault based on the information in the report. Furthermore, in specific implementations, the fault report may also carry information such as the fault type.
[0050] In the second determination method, the session management function network element in the home network receives fault reports from other network elements (such as V-SMF network elements) besides the first user plane function network element, and determines that the first user plane function network element is faulty based on the fault reports. Furthermore, in specific implementations, the session management function network element in the home network can also use other methods to determine whether the first user plane function network element is faulty.
[0051] In step S22, the first HR PDU session established for the user equipment via the first user plane function element is released.
[0052] User equipment is a device that has a contract with its home network and is located in the access area (or access area network). User equipment, also known as a terminal or terminal device, is a device with wireless transceiver capabilities that can communicate with one or more core networks via access network devices in a (wireless) access network.
[0053] In some examples, the session management function network element in the home network uses Session and Service Continuity mode 2 (SSC mode 2) to manage user equipment sessions. In these examples, step S22 is executed first, followed by step S23.
[0054] In other examples, the session management function network element in the home network uses Session and Service Continuity mode 3 (SSC mode 3) to manage user equipment sessions. In these examples, step S23 is executed first, followed by step S22.
[0055] In some other examples, the session management function network element in the home network first determines the session and service continuity mode corresponding to the user equipment; based on the session and service continuity mode corresponding to the user equipment, steps S22 and S23 are executed.
[0056] In some examples, the process of releasing the first HR PDU session includes: the H-SMF network element sending an N4 session release request to the first UPF network element to instruct the first UPF network element to release session-related resources; receiving an N4 session release response from the first UPF network element; and the H-SMF network element sending a session release instruction to the Session Management Function (V-SMF) network element in the accessed network to release session-related resources through the V-SMF network element. Furthermore, in specific implementations, the session release process may also include signaling flows between the V-SMF network element and the Access and Mobility Management Function (V-AMF) network element in the accessed network, and between the V-AMF network element and the UE, to enable the network elements involved in the first HR PDU session to release corresponding resources. For information on these inter-network element signaling flows, please refer to the relevant content on session release in 3GPP.
[0057] For example, the first HR PDU session can be a session that inserts an uplink splitter function, and the uplink splitter function is implemented through a first user plane function network element. In these examples, the process of releasing the first HR PDU session includes: deleting the ULCL node information and PSA node information corresponding to the first HR PDU session from local storage.
[0058] In step S23, a second HR PDU session is established for the user equipment via the second user plane function network element in the home network.
[0059] The second user plane function network element is deployed in the home location. For example, the second user plane function network element can be an H-UPF network element deployed in the home location.
[0060] In some examples, establishing a second HR PDU session in a home network session management function element includes: selecting a second user plane function element; sending a session request to the second user plane function element; and receiving a session response from the second user plane function element. Additionally, establishing a second HR PDU session may also include the following steps: updating locally stored session context information.
[0061] The selection of the second user plane function network element can be implemented in several exemplary ways. Two exemplary methods are described below.
[0062] In a first exemplary approach, selecting the second user plane function network element includes: selecting the second user plane function network element from multiple user plane function network elements deployed in the home location and belonging to the home network, according to the set selection criteria.
[0063] In the second exemplary approach, selecting the second user plane function network element includes: determining whether the access location has other user plane function network elements belonging to the home network besides the first user plane function network element; if the access location does not have other user plane function network elements belonging to the home network besides the first user plane function network element, or if other user plane function network elements do not meet the set selection criteria, selecting the second user plane function network element from multiple user plane function network elements deployed in the home location and belonging to the home network. In specific implementation, the selection criteria used to select H-UPF network elements from H-UPF network elements deployed in the home location can be the same as or different from the selection criteria used to select H-UPF network elements deployed in the access location.
[0064] In the second exemplary approach, the communication method may further include: if there is a network element (which may be referred to as a third user plane function network element) that meets the selection criteria among the other user plane function network elements, establishing a third HR PDU session for the user equipment via the third user plane function network element.
[0065] Updating locally stored session context information can be achieved in several exemplary ways. The following explanation uses one such method.
[0066] In one exemplary manner, updating the locally stored session context information includes: updating the Domain Name System (DNS) server information corresponding to the first HR PDU session to the DNS server information corresponding to the second HR PDU session; and updating the user plane path information corresponding to the first HR PDU session to the user plane path information corresponding to the second HR PDU session.
[0067] The DNS server corresponding to the first HR PDU session is deployed in the access location. The DNS server information corresponding to the first HR PDU session can be the address information of the DNS server deployed in the access location, or it can be the address information of the Edge Application Server Discovery Function (EASDF) deployed in the access location.
[0068] The DNS server corresponding to the second HR PDU session is deployed in the home region. The DNS server information for the second HR PDU session can be the address information of the DNS server deployed in the home region, or the address information of the EASDF deployed in the home region.
[0069] In this embodiment of the disclosure, by updating the DNS server information of the access location to the DNS server information of the home location, it is easier to communicate with the DNS server or EASDF that is closer to the second user plane functional network element, thus saving the data transmission overhead in the roaming scenario.
[0070] User plane path information includes information about the nodes that user equipment (HRPDU) must traverse to transmit data between the user equipment and the data network. For example, information about UPF network elements. In some examples, the first HR PDU session supports uplink splitter functionality, which is implemented through the first user plane function network element. In these examples, updating the user plane path information may include updating the uplink splitter information and PDU session anchor information corresponding to the first HRPDU session to the uplink splitter information and PDU session anchor information corresponding to the second HR PDU session.
[0071] In this embodiment of the disclosure, on the one hand, by deploying a first user plane function network element in the home network at the access location, data offloading is enabled through the first user plane function network element, thereby enhancing the home network's control and management of roaming data (such as billing management, QoS flow management, etc.). On the other hand, by designing... Figure 1 The signaling flow shown can ensure the continuity of roaming services when the first user plane functional network element fails.
[0072] Figure 3 This is a flowchart illustrating a communication method according to other embodiments of this disclosure. For example... Figure 3 As shown, the communication method includes steps 301 to 304.
[0073] In step 301, the first HR PDU session is established.
[0074] In this embodiment of the disclosure, the User Equipment (UE) is located in the access location and establishes a first HR PDU session through the cooperation of network elements in the VPLMN and HPLMN. Specifically, the first HR PDU session is a communication between the UE and the data network in a home-location routing scenario, via the V-UPF and the H-UPF of the access location (i.e., the H-UPF of the access location). Figure 3 In some examples, establishing the first HR PDU session involves: the User Equipment (UE) sending a first HRPDU session establishment request to the Access and Mobility Management Function (AMF) in the visited network via the Radio Access Network (RAN); the AMF selecting an SMF that supports the Home Session Breakout in HomeRouted (HR-HSBO) mechanism, such as... Figure 3V-SMF and H-SMF; H-SMF is selected as a UPF deployed in the access location that belongs to the home network, for example Figure 3 User plane function (Remote H-UPF) in the remote home network; H-SMF establishes an N4 session with Remote H-UPF.
[0075] The HR-HSBO mechanism can be understood as a mechanism that deploys user plane function network elements in the home network at the access location and uses these user plane function network elements to achieve roaming data offloading.
[0076] In practice, the process of establishing the first HR PDU session includes, in addition to the steps mentioned above, the H-SMF sending a PDU session establishment response to the V-SMF, as well as signaling procedures between the V-SMF and AMF, between the AMF and RAN, and between the RAN and UE. For specific signaling procedures, please refer to the relevant content on establishing a PDU session in the 3GPP standard.
[0077] In step 302, the Remote H-UPF sends a fault report to the H-SMF.
[0078] The fault report carries the identifier of the access network, such as the VPLMN identifier. After receiving the fault report, the H-SMF can determine which Remote H-UPF deployed in which access location has failed based on the access network identifier, which facilitates accurate subsequent H-UPF handover to maintain the continuity of roaming services.
[0079] In step 303, the first HR PDU session is released.
[0080] In this embodiment of the disclosure, the first HR PDU session is released by the cooperation of network elements in the VPLMN and HPLMN.
[0081] In some examples, H-SMF uses SSC mode 2 to manage user equipment sessions. In these examples, step 303 is executed first, followed by step 304.
[0082] For details on how to implement step 303, please refer to the aforementioned content.
[0083] In step 304, a second HR PDU session is established.
[0084] In this embodiment of the disclosure, a second HR PDU session is established by the cooperation of network elements in the VPLMN and HPLMN.
[0085] In some examples, establishing a second HR PDU session includes: the H-SMF selecting an H-UPF deployed in the home region; the H-SMF instructing the H-UPF deployed in the home region (i.e., Figure 3 The H-SMF instructs the H-UPF deployed in the home location to establish a user plane connection. This may further include: the H-SMF sending an N4 session request to the H-UPF; and the H-UPF sending an N4 session response to the H-SMF.
[0086] In some examples, establishing a second HR PDU session also includes updating the locally stored session context information. For instance, after receiving an N4 session response, the H-SMF directly updates the locally stored session context information. Another example is when the H-UPF deployed in the home network sends a session update request to the H-SMF, the H-SMF updates its locally stored session context information. Yet another example is when the H-SMF receives a session update request from another network element (such as the V-SMF), the H-SMF updates its locally stored session context information.
[0087] Specifically, H-SMF updating the locally stored session context information may include: updating the DNS server information corresponding to the locally stored session, and updating the user plane path information corresponding to the locally stored session. When the first HR PDU session supports ULCL functionality, updating the user plane path information includes: updating the ULCL node and PSA node information corresponding to the session.
[0088] In addition to the steps mentioned above, the process for establishing a second HR PDU session may also include signaling procedures between V-SMF and AMF, between AMF and RAN, and between RAN and UE. For specific signaling procedures, please refer to the relevant content on PDU session reconstruction in the 3GPP standard.
[0089] In this embodiment of the disclosure, the above process enables support for the new HR-HSBO mechanism, enhancing the home network's control and management of roaming data. Furthermore, through design... Figure 3 The signaling flow shown can ensure the continuity of roaming services in the event of a Remote H-UPF failure.
[0090] Figure 4 This is a schematic diagram of the structure of a communication device according to some embodiments of the present disclosure. For example... Figure 4 As shown, the communication device 400 includes an acquisition module 41, a session release module 42, and a session establishment module 43.
[0091] The detection module 41 is configured to detect faults in the first user plane function network element in the home network. The first user plane function network element is deployed in the access location.
[0092] Session release module 42 is configured to release the first HR PDU session established for the user equipment via the first user plane function network element. The user equipment is subscribed to by the home network and is located in the access area.
[0093] Session establishment module 43 is configured to establish a second HR PDU session for the user equipment via a second user plane function network element in the home network. The second user plane function network element is deployed in the home network.
[0094] In this embodiment of the disclosure, the above-mentioned device can realize a new user plane function network element fault handling process in roaming scenarios, ensuring the continuity of roaming services.
[0095] Figure 5 This is a schematic diagram of the structure of a communication device according to other embodiments of this disclosure. For example... Figure 5 As shown, the communication device 50 is disposed in a session management function network element in the home network, including a memory 51 and a processor 52 coupled to the memory 51. The memory 51 is used to store instructions for executing embodiments of the communication method. The processor 52 is configured to execute the communication method in any of the embodiments of this disclosure based on the instructions stored in the memory 51.
[0096] Figure 6 This is a schematic diagram of the structure of a communication system according to some embodiments of this disclosure. For example... Figure 6 As shown, the communication system 60 includes an SMF network element 61 in the home network, a first UPF network element 62 in the home network, and a second UPF network element 63 in the home network. The first UPF network element 62 is deployed at the access location, and the second UPF network element 63 is deployed at the home location.
[0097] SMF element 61 is used to establish a first HR PDU session for user equipment roaming to the access location via the first UPF element.
[0098] SMF network element 61 is also used to release the first HR PDU session after determining that the first UPF network element 62 is faulty, and to establish a second HR PDU session for the user equipment via the second UPF network element 63.
[0099] For details on how SMF network elements release the first HR PDU session and how to establish the second HR PDU session, please refer to the aforementioned related instructions.
[0100] The first UPF network element 62 is used to assist the SMF network element 61 in releasing the first HR PDU session.
[0101] The second UPF network element 63 is used to assist the SMF network element 61 in establishing a second HR PDU session.
[0102] In this embodiment of the disclosure, the communication method described above is achieved through the cooperation of various devices in the communication system. This system enhances the home network's control and management of roaming data, and ensures the continuity of roaming services in the event of a failure of the first UPF network element.
[0103] Various aspects of this disclosure are described herein with reference to flowchart illustrations and / or block diagrams of methods, apparatus, and computer program products according to embodiments of this disclosure. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations thereof, can be implemented by computer-readable program instructions.
[0104] These computer-readable program instructions are provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable device to produce a machine, such that execution of the instructions by the processor produces means for implementing the functions specified in one or more boxes of the flowchart and / or block diagram.
[0105] These computer-readable program instructions may also be stored in a computer-readable storage medium. These instructions cause a computer to work in a particular manner to produce an article of manufacture, including instructions that implement the functions specified in one or more boxes in a flowchart and / or block diagram.
[0106] This disclosure may take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects.
[0107] The communication methods, apparatus, and systems according to this disclosure have now been described in detail. To avoid obscuring the concept of this disclosure, some details known in the art have not been described. Those skilled in the art can fully understand how to implement the technical solutions disclosed herein based on the above description.
Claims
1. A communication method, executed by a session management function network element in a home network, comprising: The fault of the first user plane function network element in the home network is known, wherein the first user plane function network element is deployed in the access location; Release the first Home Routing Protocol Data Unit (HR PDU) session established for the user equipment via the first user plane functional network element; Establish a second HR PDU session for the user equipment via a second user plane function network element in the home network, wherein the second user plane function network element is deployed in the home network.
2. The communication method according to claim 1, wherein, The establishment of the second HR PDU session via the second user plane function element in the home network includes: Select the second user plane function element; Send a session request to the second user plane function network element; Receive session response from the second user plane function network element.
3. The communication method according to claim 2, wherein, The establishment of the second HR PDU session via the second user plane function element in the home network also includes: Update the locally stored session context information.
4. The communication method according to claim 3, wherein, The updated locally stored session context information includes: Update the DNS server information corresponding to the first HRPDU session to the DNS server information corresponding to the second HRPDU session, wherein the DNS server corresponding to the first HRPDU session is deployed in the access location, and the DNS server corresponding to the second HRPDU session is deployed in the home location; and / or Update the user plane path information corresponding to the first HR PDU session to the user plane path information corresponding to the second HR PDU session.
5. The communication method according to claim 2, wherein, The selection of the second user plane function network element includes: If no other user plane function network element (MPF) belonging to the home network exists at the access location besides the first MPF, or if other MPFs exist at the access location but do not meet the set selection criteria, the second MPF is selected from the MPFs deployed at the home location that belong to the home network.
6. The communication method according to claim 5 further includes: If there is a network element among the other user plane function network elements that meets the selection criteria, a third HR PDU session is established for the user equipment via the network element that meets the selection criteria.
7. The communication method according to claim 4, wherein, The step of updating the user plane path information corresponding to the first HR PDU session to the user plane path information corresponding to the second HR PDU session includes: Update the uplink splitter information and PDU session anchor information corresponding to the first HR PDU session to the uplink splitter information and PDU session anchor information corresponding to the second HR PDU session.
8. The communication method according to any one of claims 1 to 7, wherein, The first user plane function network element supports uplink splitter function and PDU session anchor point function established for the first HR PDU session.
9. The communication method according to any one of claims 1 to 7, wherein, The knowledge of a fault in the first user plane function network element in the home network includes: Receive fault reports from the first user plane functional network element; Based on the fault report, the first user plane function network element is determined to be faulty.
10. The communication method according to claim 9, wherein the fault report carries an identifier of the accessed network.
11. A communication device, configured in a session management function network element in a home network, comprising: The acquisition module is configured to acquire information about a fault in a first user plane function network element in the home network, wherein the first user plane function network element is deployed in the access location; The session release module is configured to release the first Home Routing Protocol Data Unit (HR PDU) session established for the user equipment via the first user plane functional network element; The session establishment module is configured to establish a second HR PDU session for the user equipment via a second user plane function network element in the home network, wherein the second user plane function network element is deployed in the home network.
12. A communication device, comprising: Memory; as well as A processor coupled to the memory, the processor being configured to execute the communication method as described in any one of claims 1 to 10 based on instructions stored in the memory.
13. A communication system, comprising: The session management function network element in the home network includes the communication device as described in claim 11 or 12; The first user plane function network element is configured to assist the session management function network element in releasing the first HR PDU session; as well as The second user plane function network element is configured to assist the session management function network element in establishing a second HR PDU session.
14. A computer-readable storage medium having stored thereon computer program instructions that, when executed by a processor, implement the communication method as described in any one of claims 1 to 10.
15. A computer program product having stored computer program instructions thereon, which, when executed by a processor, implement the communication method as described in any one of claims 1 to 10.