Mobility management methods, apparatus and network side device

Abstract

The present application belongs to the technical field of communications. Disclosed are mobility management methods, an apparatus and a network side device. A mobility management method of the present application comprises: when a first condition is met, a first network entity sends a target message to a second network entity, the target message being used for requesting allocating an evolved packet system (EPS) bearer identity (EBI), and the first condition comprising: a terminal is switched or reselected from a second mobile communication system to a first mobile communication system and, among protocol data unit (PDU) sessions corresponding to the first mobile communication system, there is a target PDU session that can be switched or reselected to a third mobile communication system, wherein the first mobile communication system is a fifth generation mobile communication system, and the third mobile communication system is a fourth generation mobile communication system.

Description

Mobility management methods, devices and network-side equipment

[0001] Cross-reference to related applications

[0002] This application claims priority to Chinese Patent Application No. 202411946294.7, filed in China on December 27, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application belongs to the field of communication technology, specifically relating to a mobility management method, apparatus, and network-side equipment. Background Technology

[0004] With the development of communication systems, terminals can typically move between different systems. For example, a terminal can move from a sixth-generation mobile communication system (6G) to a third-generation mobile communication system (6G). th Switching or reselecting from 6G to 5G mobile communication systems (5G) th 5G (5G) mobile communication systems are emerging; however, during handover or reselection, if the Internet Protocol (IP) address changes, service interruption will occur. Therefore, ensuring service continuity has become a pressing issue. Summary of the Invention

[0005] This application provides a mobility management method, apparatus, and network-side device that can solve the problem of how to ensure service continuity.

[0006] Firstly, a mobility management method is provided, including:

[0007] If the first condition is met, the first network entity sends a target message to the second network entity, the target message being used to request the allocation of an evolved packet system EPS bearer identifier (EBI).

[0008] The first condition includes:

[0009] The terminal switches or reselects from the second mobile communication system to the first mobile communication system;

[0010] The protocol data unit (PDU) session corresponding to the first mobile communication system contains a target PDU session that can be switched or reselected to the third mobile communication system.

[0011] The first mobile communication system is a fifth-generation mobile communication system, and the third mobile communication system is a fourth-generation mobile communication system.

[0012] Secondly, a mobility management method is provided, including:

[0013] The second network entity receives a target message from the first network entity, the target message being used to request the allocation of an Evolved Packet System EPS Bearer Identifier (EBI).

[0014] The target message is triggered based on a first condition, which includes:

[0015] The terminal switches or reselects from the second mobile communication system to the first mobile communication system;

[0016] The protocol data unit (PDU) session corresponding to the first mobile communication system contains a target PDU session that can be switched or reselected to the third mobile communication system.

[0017] Wherein, the first mobile communication system is a fifth-generation mobile communication system, and the third mobile communication system is a fourth-generation mobile communication system. Thirdly, a mobility management device is provided, comprising:

[0018] The first sending module is used to send a target message to the second network entity when a first condition is met. The target message is used to request the allocation of an evolved packet system EPS bearer identifier (EBI).

[0019] The first condition includes:

[0020] The terminal switches or reselects from the second mobile communication system to the first mobile communication system;

[0021] The protocol data unit (PDU) session corresponding to the first mobile communication system contains a target PDU session that can be switched or reselected to the third mobile communication system.

[0022] The first mobile communication system is a fifth-generation mobile communication system, and the third mobile communication system is a fourth-generation mobile communication system.

[0023] Fourthly, a mobility management device is provided, comprising:

[0024] The second receiving module is used to receive a target message from the first network entity, the target message being used to request the allocation of an Evolved Packet System EPS Bearer Identifier (EBI).

[0025] The target message is triggered based on a first condition, which includes:

[0026] The terminal switches or reselects from the second mobile communication system to the first mobile communication system;

[0027] The protocol data unit (PDU) session corresponding to the first mobile communication system contains a target PDU session that can be switched or reselected to the third mobile communication system.

[0028] The first mobile communication system is a fifth-generation mobile communication system, and the third mobile communication system is a fourth-generation mobile communication system.

[0029] Fifthly, a mobility management device is provided, the device being configured to perform the steps of the method described in the first aspect, or to implement the steps of the method described in the second aspect.

[0030] In a sixth aspect, a network-side device is provided, the network-side device including a processor and a memory, the memory storing a program or instructions executable on the processor, the program or instructions, when executed by the processor, implementing the steps of the method as described in the first aspect, or implementing the steps of the method as described in the second aspect.

[0031] In a seventh aspect, a network-side device is provided, including a processor and a communication interface, wherein,

[0032] When the network-side device is the first network entity, the communication interface is used to send a target message to the second network entity under the condition of satisfying the first condition. The target message is used to request the allocation of an evolved packet system EPS bearer identifier (EBI).

[0033] The first condition includes:

[0034] The terminal switches or reselects from the second mobile communication system to the first mobile communication system;

[0035] The protocol data unit (PDU) session corresponding to the first mobile communication system contains a target PDU session that can be switched or reselected to the third mobile communication system.

[0036] The first mobile communication system is a fifth-generation mobile communication system, and the third mobile communication system is a fourth-generation mobile communication system.

[0037] When the network-side device is the second network entity, the communication interface is used to receive a target message from the first network entity. The target message is used to request the allocation of an evolved packet system EPS bearer identifier (EBI).

[0038] The target message is triggered based on a first condition, which includes:

[0039] The terminal switches or reselects from the second mobile communication system to the first mobile communication system;

[0040] The protocol data unit (PDU) session corresponding to the first mobile communication system contains a target PDU session that can be switched or reselected to the third mobile communication system.

[0041] The first mobile communication system is a fifth-generation mobile communication system, and the third mobile communication system is a fourth-generation mobile communication system.

[0042] Eighthly, a readable storage medium is provided, on which a program or instructions are stored, which, when executed by a processor, implement the steps of the method described in the first aspect, or implement the steps of the method described in the second aspect.

[0043] A ninth aspect provides a wireless communication system, comprising: a first network entity and a second network entity, wherein the first network entity is configured to perform the steps of the method described in the first aspect, and the second network entity is configured to perform the steps of the method described in the second aspect.

[0044] In a tenth aspect, a chip is provided, the chip including a processor and a communication interface coupled to the processor, the processor being configured to run a program or instructions to implement the steps of the method described in the first aspect, or to implement the steps of the method described in the second aspect.

[0045] Eleventhly, a computer program / program product is provided, the computer program / program product being stored in a storage medium, the computer program / program product being executed by at least one processor to implement the steps of the method as described in the first aspect, or to implement the steps of the method as described in the second aspect.

[0046] In this embodiment, under a first condition, a first network entity sends a target message to a second network entity to request the allocation of an Evolved Packet System EPS Bearer Identifier (EBI). The first condition includes: the terminal switching or reselecting from a second mobile communication system to a first mobile communication system; and the existence of a target PDU session in the Protocol Data Unit (PDU) session corresponding to the first mobile communication system that can be switched or reselected to a third mobile communication system. The first mobile communication system is a fifth-generation mobile communication system, and the third mobile communication system is a fourth-generation mobile communication system. Thus, after the terminal switches from the second mobile communication system to 5G, the first network entity's request to allocate an EBI for the terminal ensures that the 5G PDU session can be further migrated to 4G, guaranteeing the continuity of terminal services. Attached Figure Description

[0047] Figure 1 is a block diagram of a wireless communication system applicable to an embodiment of this application;

[0048] Figure 2 is an example of a mapping between QoS flow and EPS bearer that can be applied to an embodiment of this application;

[0049] Figure 3 is a flowchart illustrating one of the mobility management methods provided in this application embodiment;

[0050] Figure 4 is a second schematic flowchart of a mobility management method provided in an embodiment of this application;

[0051] Figure 5 is a third flowchart illustrating a mobility management method provided in an embodiment of this application;

[0052] Figure 6 is a fourth flowchart illustrating a mobility management method provided in an embodiment of this application;

[0053] Figure 7 is a schematic diagram of a mobility management device provided in an embodiment of this application;

[0054] Figure 8 is a schematic diagram of another mobility management device provided in an embodiment of this application;

[0055] Figure 9 is a schematic diagram of the structure of a communication device provided in an embodiment of this application;

[0056] Figure 10 is a schematic diagram of the structure of a network-side device provided in an embodiment of this application. Detailed Implementation

[0057] The terms "first," "second," etc., used in this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first" and "second" are generally of the same class, not limited in number; for example, the first object can be one or more. Furthermore, "or" in this application indicates at least one of the connected objects. For example, the scope of protection for "A or B" covers at least three scenarios: Scenario 1: including A but not B; Scenario 2: including B but not A; Scenario 3: including both A and B. In addition, the terms "A and / or B," "at least one of A and B," and "at least one of A or B" also cover at least the above three scenarios. The character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0058] The term "instruction" in this application can be either a direct instruction (or explicit instruction) or an indirect instruction (or implicit instruction). A direct instruction can be understood as the sender explicitly informing the receiver of specific information, the required operation, or the requested result in the instruction sent. An indirect instruction can be understood as the receiver determining the corresponding information based on the instruction sent by the sender, or making a judgment and determining the required operation or requested result based on the judgment result.

[0059] It is worth noting that the technologies described in this application are not limited to Long Term Evolution (LTE) / LTE-Advanced (LTE-A) systems, but can also be used in other wireless communication systems, such as Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Orthogonal Frequency Division Multiple Access (OFDMA), Single-carrier Frequency-Division Multiple Access (SC-FDMA), or other systems. The terms "system" and "network" in this application are often used interchangeably, and the described technologies can be used with the systems and radio technologies mentioned above, as well as with other systems and radio technologies. The following description describes New Radio (NR) systems for illustrative purposes, and the term NR is used in most of the following description; however, these technologies can also be applied to systems other than NR systems, such as 6th generation (6G) radio systems. th Generation 6G communication system.

[0060] Figure 1 shows a block diagram of a wireless communication system applicable to an embodiment of this application. The wireless communication system includes a terminal 11 and a network-side device 12. The terminal 11 can also be referred to as User Equipment (UE), and can be a mobile phone, tablet computer, laptop computer, notebook computer, personal digital assistant (PDA), handheld computer, netbook, ultra-mobile personal computer (UMPC), mobile internet device (MID), augmented reality (AR), virtual reality (VR) device, robot, wearable device, flight vehicle, vehicle user equipment (VUE), shipboard equipment, pedestrian user equipment (PUE), smart home (home devices with wireless communication capabilities, such as refrigerators, televisions, washing machines, or furniture), game console, personal computer (PC), ATM, or self-service machine, etc. Wearable devices include: smartwatches, smart bracelets, smart headphones, smart glasses, smart jewelry (smart bracelets, smart chains, smart rings, smart necklaces, smart anklets, smart anklets, etc.), smart wristbands, smart clothing, etc. Among these, in-vehicle devices can also be referred to as in-vehicle terminals, in-vehicle controllers, in-vehicle modules, in-vehicle components, in-vehicle chips, or in-vehicle units, etc. Furthermore, terminal 11 can be any of the terminals described above, or it can be a chip within a terminal, such as a modem chip, a system-on-chip (SoC), etc. It should be noted that the specific type of terminal 11 is not limited in this application embodiment. Network-side equipment 12 can include access network equipment or core network equipment, wherein access network equipment can also be referred to as Radio Access Network (RAN) equipment, radio access network function, or radio access network unit. Access network equipment can include base stations, Wireless Local Area Network (WLAN) access points (APs), or Wireless Fidelity (WiFi) nodes, etc.Among them, base stations can be referred to as Node B (NB), Evolved Node B (eNB), Next Generation Node B (gNB), New Radio Node B (NR Node B), Access Point, Relay Base Station (RBS), Serving Base Station (SBS), Base Transceiver Station (BTS), Radio Base Station, Radio Transceiver, Basic Service Set (BSS), Extended Service Set (ESS), Home Node B (HNB), Home Evolved Node B, Transmit / Receive Point (TRP), Non-Terrestrial Network (NTN) equipment (such as satellite or high altitude platform stations). The term "base station" can be any suitable term in the field, such as "station" or any other appropriate term in the relevant field, as long as the same technical effect is achieved. The term "base station" is not limited to specific technical terms. It should be noted that the embodiments of this application only use the base station in the NR system as an example for introduction, and do not limit the specific type of base station.

[0061] Core network equipment, also known as core network nodes, core network functions, or core network elements, includes, but is not limited to, at least one of the following: Mobility Management Entity (MME), Access and Mobility Management Function (AMF), Session Management Function (SMF), User Plane Function (UPF), Policy Control Function (PCF), Policy and Charging Rules Function (PCRF), Edge Application Server Discovery Function (EASDF), Unified Data Management (UDM), Unified Data Repository (UDR), Home Subscriber Server (HSS), Centralized network configuration (CNC), Network Repository Function (NRF), Network Exposure Function (NEF), Local NEF (L-NEF), and Binding Support. Functions include BSF, Application Function (AF), Location Management Function (LMF), Gateway Mobile Location Centre (GMLC), Network Data Analytics Function (NWDAF), and Non-Terrestrial Network (NTN) equipment (such as satellite or high altitude platform station).It should be noted that the embodiments of this application only use the core network equipment in the NR system as an example for introduction, and do not limit the specific type of core network equipment. If the name of the core network equipment mentioned in the embodiments of this application changes in subsequent protocol versions (e.g., 6G), it is also within the scope of protection of this application.

[0062] Optionally, the core network equipment can be implemented by one or more functional modules in a single device, or by multiple devices working together; this application does not specifically limit this. It is understood that the aforementioned functional modules can be network elements in hardware devices, software functional modules running on dedicated hardware, or virtualized functional modules instantiated on a platform (e.g., a cloud platform).

[0063] For ease of understanding, the following describes some aspects of the embodiments of this application:

[0064] Terminals switch from 5G to fourth-generation mobile communication systems (4G). th In 4G (4G) generation mobile communication systems, the granularity of 5G Quality of Service (QoS) is finer than that of 4G. Multiple 5G QoS flows can be mapped to a single Evolved Packet System (EPS) bearer, as shown in Figure 2. Due to this many-to-one mapping relationship, the 5G SMF+ Packet Data Network Gateway Control Plane (PGW-C) cannot locally map 5G QoS flow parameters to EPS bearer parameters.

[0065] To ensure service continuity when a terminal switches from 5G to 4G, the EPS bearer parameters corresponding to the QoS flow need to be prepared in advance within 5G, including the Evolved Packet System (EPS) bearer ID (EBI) parameter and the mapped EPS bearer QoS.

[0066] Among them, EBI is allocated to the terminal by the SMF+PGW-C requesting the AMF during the process of establishing or modifying a Protocol Data Unit (PDU) session within 5G.

[0067] The UE establishes a PDU session within 6G. When the UE switches or reselects from 6G to 5G, the interworking 6G PDU session will be mapped to the corresponding 5G PDU session, while ensuring that the IP address remains unchanged, so that the user's service will not be interrupted.

[0068] Because the mapped 5G PDU session lacks some key 4G parameters, such as EBI, the 5G PDU session cannot maintain its IP address when the UE switches from 5G to 4G, resulting in service interruption and impacting user experience. This application proposes a mobility management method to address this issue.

[0069] The mobile management method provided in this application will be described in detail below with reference to the accompanying drawings and through some embodiments and application scenarios.

[0070] Referring to Figure 3, an embodiment of this application provides a mobility management method, as shown in Figure 3, the mobility management method includes:

[0071] Step 301: If the first condition is met, the first network entity sends a target message to the second network entity, the target message being used to request the allocation of an evolved packet system EPS bearer identifier (EBI).

[0072] The first condition includes:

[0073] The terminal switches or reselects from the second mobile communication system to the first mobile communication system;

[0074] The protocol data unit (PDU) session corresponding to the first mobile communication system contains a target PDU session that can be switched or reselected to the third mobile communication system.

[0075] The first mobile communication system is a fifth-generation mobile communication system, and the third mobile communication system is a fourth-generation mobile communication system.

[0076] In this embodiment, the first condition can be understood as a condition for triggering the EBI allocation process. When the first condition is met, the EBI allocation process will be triggered. During the EBI allocation process, the first network entity will send a target message to the second network entity. This target message may include a request message. Since the first network entity requests EBI allocation for the terminal when the first condition is met, it ensures that the 5G PDU session can be further moved to 4G, guaranteeing IP continuity and preventing terminal service interruptions. Therefore, this embodiment improves the reliability of terminal services.

[0077] Optionally, the target message may include a 5G PDU session ID and an Allocation and Retention Priority (ARP) list.

[0078] It should be noted that the number of ARP entries in the ARP list represents the number of EBI requests that need to be made.

[0079] It should be noted that the movement in the embodiments of this application can be understood or replaced as: switching or reselection.

[0080] Optionally, the first network entity may include an SMF (Super Memory Function), for example, the first network entity may be a 5G SMF, which may be a 6G SMF + 5G SMF + PGW-C, or a standalone 5G SMF. The second network entity may include an AMF (Advanced Feature Memory Function), for example, a 5G AMF.

[0081] In this embodiment, under a first condition, a first network entity sends a target message to a second network entity to request the allocation of an Evolved Packet System EPS Bearer Identifier (EBI). The first condition includes: the terminal switching or reselecting from a second mobile communication system to a first mobile communication system; and the existence of a target PDU session in the Protocol Data Unit (PDU) session corresponding to the first mobile communication system that can be switched or reselected to a third mobile communication system. The first mobile communication system is a fifth-generation mobile communication system, and the third mobile communication system is a fourth-generation mobile communication system. Thus, after the terminal switches from the second mobile communication system to 5G, the first network entity's request to allocate an EBI for the terminal ensures that the 5G PDU session can be further migrated to 4G, guaranteeing the continuity of terminal services.

[0082] Optionally, in some embodiments, the first condition further includes:

[0083] The target PDU session does not have an EBI stored or exists in its context.

[0084] In this embodiment of the application, if an EBI is not allocated by default in the second mobile communication system, it is not necessary to determine whether an EBI is saved or exists in the context of the target PDU session. If an EBI can be allocated in the second mobile communication system, it is necessary to further determine whether an EBI is saved or exists in the context of the target PDU session. Only when an EBI is not saved or does not exist in the context of the target PDU session is it necessary for the first network entity to send a target message to the second network entity to request the second network entity to allocate an EBI for the terminal.

[0085] Optionally, in some embodiments, the method further includes:

[0086] The first network entity receives the target EBI allocated for the terminal from the second network entity;

[0087] The first network entity sends the target EBI to the target device;

[0088] The target device includes at least one of a terminal, a third network entity, and an access network device.

[0089] In this embodiment of the application, after receiving the target message, the second network entity can allocate a target EBI to the terminal and send the allocated target EBI to the first network entity; after receiving the target EBI, the first network entity can send the target EBI to the target device.

[0090] Optionally, the target PDU session may include one or more PDU sessions. The target EBI may include the EBI corresponding to each PDU session.

[0091] Optionally, in some embodiments, the first network entity sending the target EBI to the target device includes at least one of the following:

[0092] The first network entity sends a PDU session modification message to the terminal, the PDU session modification message containing the EBI;

[0093] The first network entity sends an N4 session modification message to the third network entity, the N4 session modification message containing the EBI;

[0094] The first network entity sends N2 Session Management (SM) information to the access network device, and the N2 SM information includes the EBI.

[0095] As an example, the first network entity sending a PDU session modification message to the terminal may include: the first network entity sending the EBI corresponding to the received PDU session to the terminal via the PDU session modification message. The first network entity sending an N4 session modification message to the third network entity may include: the first network entity sending the EBI corresponding to the received PDU session to the third network entity via the N4 session modification message. The first network entity sending N2 SM information to the access network device may include: the first network entity sending the EBI corresponding to the received PDU session to the access network device via the N2 SM information.

[0096] It should be noted that, in this embodiment of the application, the first network entity performs the following steps for each PDU session in the target PDU session:

[0097] The first network entity sends the EBI corresponding to the received PDU session to the third network entity via the N4 session modification message;

[0098] The first network entity sends the EBI corresponding to the received PDU session to the terminal and access network equipment through the PDU session modification process.

[0099] Optionally, the aforementioned third network entity may include a UPF, for example, the UPF may be a 5G UPF or a 5GUPF+PGW-U.

[0100] Optionally, in some embodiments, the method further includes:

[0101] The first network entity sends target indication information to the second network entity, the target indication information being used to instruct the terminal to switch or reselect from the second mobile communication system to the first mobile communication system.

[0102] Optionally, in some embodiments, the target message includes at least one of the following:

[0103] EBI allocation request message;

[0104] Create an SM context response message.

[0105] In this embodiment, the EBI allocation request message can be understood as a newly defined message. When the target message includes the EBI allocation request message, it can be assumed that the first network entity sends an independent message requesting the second network entity to allocate an EBI. The aforementioned create SM context response message can be understood as a response message to the create SM context request message. When the target message includes the create SM context response message, it can be assumed that the first network entity requests the second network entity to allocate an EBI through the create SM context response message.

[0106] Optionally, the target message includes: an EBI allocation request message and a Create SM Context Response message. This can be understood as the newly defined message being sent together with the Create SM Context Response message to request the second network entity to allocate an EBI.

[0107] Optionally, in some embodiments, the second mobile communication system is a sixth-generation mobile communication system or a seventh-generation mobile communication system.

[0108] To better understand this application, some examples are provided below.

[0109] In some embodiments, as shown in Figure 4, the switching process from 6G to 5G for a terminal specifically includes the following steps:

[0110] Step 41, the handover preparation stage for the terminal to switch from 6G to 5G;

[0111] Step 42: The 6G AMF sends a handover command to the 6G RAN;

[0112] Step 43: The 6G RAN sends a handover command to the terminal, instructing the UE to switch from 6G to 5G;

[0113] Step 44: The terminal accesses the 5G network according to the handover command and sends a handover confirm message to the 5G base station.

[0114] Step 45: The 5G base station sends a handover notification to the 5G AMF to inform the AMF that the UE has switched to 5G.

[0115] Step 46: The 5G AMF sends an UpdateSMContext message (such as Nsmf_PDUSession_UpdateSMContext Request) to the 5G SMF+PGW-C to notify the PDU session that the handover has been successful.

[0116] This message will send a Handover Complete Indication for each successfully switched PDU session, indicating the successfully switched PDU session by the PDU session ID.

[0117] It should be noted that 5G SMF+PGW-C can also be a network element co-located with 6G: 6G SMF+5G SMF+PGW-C.

[0118] Step 47: 5G SMF+PGW-C sends an update message to 5G UPF+PGW-U.

[0119] It should be noted that 5G UPF+PGW-U can also be a network element co-located with 6G: 6G UPF+5G UPF+PGW-U.

[0120] Step 48: 5G SMF+PGW-C sends an acknowledgment message to 5G AMF.

[0121] Step 49: 5G SMF+PGW-C initiates the EBI allocation procedure based on the first condition.

[0122] The first condition includes:

[0123] The terminal switches or reselects from the second mobile communication system to the first mobile communication system;

[0124] The protocol data unit (PDU) session corresponding to the first mobile communication system contains a target PDU session that can be switched or reselected to the third mobile communication system.

[0125] Step 410: 5G SMF+PGW-C sends an EBI allocation request (i.e., target message) to 5G AMF, carrying the 5G PDU session ID and ARP list that can be switched to.

[0126] Optionally, the 5G SMF+PGW-C sends a target indication information for moving from 6G to 5G to the 5G AMF. This movement includes two scenarios: handover or reselection; therefore, movement can also be replaced by handover or reselection.

[0127] Optionally, the number of ARP entries in the ARP list represents the number of EBI requests that need to be made.

[0128] Step 411: If the UE meets the second condition, the 5G AMF will revoke all EBIs allocated to the UE.

[0129] The second condition includes at least one of the following:

[0130] Before the UE is migrated from 6G to 5G, an EBI has already been assigned to the UE;

[0131] The UE has been moved from 6G to 5G.

[0132] Optionally, the 5G AMF method for determining whether a UE is migrating from 6G to 5G includes:

[0133] Local determination is made based on messages received during the movement (handover or reselection) process;

[0134] Determined based on the target indication information carried in step 410.

[0135] It should be noted that 5G AMF reclaims EBIs that were allocated to the UE before the UE switched from 6G to 5G. AMF only needs to reclaim EBIs once after the UE switches from 6G to 5G and receives the first EBI allocation request; subsequent EBI allocation requests do not require reclaiming.

[0136] It should be noted that the UE-assigned EBI will be stored in the 5G AMF in the following situations:

[0137] Scenario 1: When the terminal establishes a PDU session in 5G, the 5G SMF+PGW-C requests the 5G AMF to allocate an EBI for the UE;

[0138] Scenario 2: When the UE switches or reselects from 5G to 6G, the 6G SMF or 6G SMF+5G SMF+PGW-C does not save or receive EBI information, and the 5G AMF does not reclaim the allocated EBI.

[0139] Scenario 3: When the UE switches from 6G or reselects to 5G, the 5G AMF still retains the allocated EBI.

[0140] It should be noted that 6G SMF can be understood as a network element or network entity that can be used to manage the UE's session in 6G. This network element or network entity can also be called by other names, such as Data Flow Management Function (DFMF), without further limitation here.

[0141] Step 412: 5G AMF assigns an EBI to the terminal.

[0142] Step 413: The 5G AMF sends the allocated EBI to the 5G SMF+PGW-C.

[0143] For each PDU session, 5G SMF+PGW-C executes steps 414-418.

[0144] Step 414: 5G SMF+PGW-C sends the received EBI to 5GUPF+PGW-U via the N4 session modification message.

[0145] Step 415: 5G SMF+PGW-C initiates the PDU session modification process and sends the obtained EBI to UE and 5G RAN.

[0146] Step 416: The 5G SMF+PGW-C sends an N1 / N2 message transfer (Namf_Communication_N1N2MessageTransfer) message to the 5G AMF, which includes the N1 container to be sent to the terminal and the N2 container to be sent to the terminal.

[0147] The N2 container contains EBI information corresponding to each QoS flow;

[0148] The N1 container contains PDU session modification command information, which includes EBI information for each QoS flow.

[0149] In step 417, the 5G AMF sends the N2 message to the 5G base station, and the 5G base station locally stores the EBI information corresponding to each QoS flow.

[0150] In step 418, the 5G base station sends the N1 container to the terminal, and the terminal locally saves the EBI information corresponding to each QoS flow.

[0151] It should be noted that steps 49 and 410 can also be executed after receiving step 46; or, step 410 can be combined with step 48.

[0152] In some embodiments, as shown in Figure 5, the process of a terminal reselecting from 6G to 5G specifically includes the following steps:

[0153] Step 51: The terminal establishes at least one PDU session in 6G;

[0154] Step 52: The terminal reselects to 5G;

[0155] Step 53: The terminal sends a registration request, carrying a mobility indication;

[0156] Step 54: The 5G AMF obtains the UE context from the 6G AMF;

[0157] The 5G AMF performs steps 55 to 57 for each 5G PDU session.

[0158] Step 55: The 5G AMF sends a Create SM Context Request (such as Nsmf_PDUSession_CreateSMContext Request) message to the 5G SMF+PGW-C to create the 5G PDU session context corresponding to the 6G PDU session in the 5G SMF+PGW-C.

[0159] Step 56: 5G SMF+PGW-C interacts with 5G UPF+PGW-U to modify the N4 session.

[0160] Step 57: The 5G SMF+PGW-C sends a Create SM Context response (Nsmf_PDUSession_CreateSMContext response) message to the 5G AMF.

[0161] Step 58: The 5G AMF sends a registration accept message to the terminal.

[0162] Steps 59 to 518 are the same as steps 49 to 418. For details, please refer to the embodiment shown in Figure 4, which will not be repeated here.

[0163] It should be noted that steps 59 and 510 can also be executed after receiving step 55; or, step 510 can be combined with step 57.

[0164] Referring to Figure 6, this application embodiment also provides a mobility management method, as shown in Figure 6, the mobility management method includes:

[0165] Step 601: The second network entity receives a target message from the first network entity, the target message being used to request the allocation of an Evolved Packet System EPS Bearer Identifier (EBI).

[0166] The target message is triggered based on a first condition, which includes:

[0167] The terminal switches or reselects from the second mobile communication system to the first mobile communication system;

[0168] The protocol data unit (PDU) session corresponding to the first mobile communication system contains a target PDU session that can be switched or reselected to the third mobile communication system.

[0169] The first mobile communication system is a fifth-generation mobile communication system, and the third mobile communication system is a fourth-generation mobile communication system.

[0170] Optionally, the method further includes:

[0171] The second network entity allocates a target EBI to the terminal based on the target message;

[0172] The second network entity sends the target EBI to the first network entity.

[0173] Optionally, the method further includes:

[0174] The second network entity reclaims the EBI allocated to the terminal.

[0175] Optionally, the second network entity reclaims the EBI allocated to the terminal, including:

[0176] If the second network entity determines that the second condition is met, the second network entity reclaims the EBI allocated to the terminal;

[0177] The second condition includes at least one of the following:

[0178] The second network entity assigned an EBI to the terminal;

[0179] The terminal switches or reselects from the second mobile communication system to the first mobile communication system.

[0180] Optionally, the method further includes:

[0181] The second network entity determines whether the terminal switches or reselects from the second mobile communication system to the first mobile communication system based on any of the following:

[0182] The message received by the second network entity during the switching or reselection of the terminal;

[0183] The target indication information received from the first network entity is used to instruct the terminal to switch or reselect from the second mobile communication system to the first mobile communication system.

[0184] Optionally, the first condition further includes:

[0185] The target PDU session does not have an EBI stored or exists in its context.

[0186] Optionally, the method further includes:

[0187] The second network entity receives target indication information from the first network entity, the target indication information being used to instruct the terminal to switch or reselect from the second mobile communication system to the first mobile communication system.

[0188] Optionally, the target message includes at least one of the following:

[0189] EBI allocation request message;

[0190] Create an SM context response message.

[0191] Optionally, the second mobile communication system is a sixth-generation mobile communication system or a seventh-generation mobile communication system.

[0192] This application embodiment receives a target message from a first network entity through a second network entity. The target message is used to request the allocation of an Evolved Packet System EPS Bearer Identifier (EBI). The target message is triggered based on a first condition, which includes: the terminal switching or reselecting from a second mobile communication system to a first mobile communication system; and the existence of a target PDU session in the Protocol Data Unit (PDU) session corresponding to the first mobile communication system that can be switched or reselected to a third mobile communication system. The first mobile communication system is a fifth-generation mobile communication system, and the third mobile communication system is a fourth-generation mobile communication system. Thus, after the terminal switches from the second mobile communication system to 5G, the second network entity allocates an EBI to the terminal, thereby ensuring that the 5G PDU session can be further migrated to 4G, guaranteeing the continuity of terminal services.

[0193] The mobility management method provided in this application can be executed by a mobility management device. This application uses the example of a mobility management device executing the mobility management method to illustrate the mobility management device provided in this application.

[0194] This application provides a mobility management device. As an example, the mobility management device may be a communication device or a component within a communication device, such as a chip. The communication device may be a network-side device or a server, etc. Exemplarily, the network-side device may include, but is not limited to, the types of network-side devices 12 listed above; this application does not impose specific limitations on these types.

[0195] The mobility management device includes a receiving module, a transmitting module, and a processing module. These modules can be implemented in software or hardware. When implemented in hardware, the processing module can be implemented by a processor. For example, the processor can include a general-purpose processor, a special-purpose processor, such as a Central Processing Unit (CPU), a microprocessor, a Digital Signal Processor (DSP), an Artificial Intelligence (AI) processor, a Graphics Processing Unit (GPU), an Application Specific Integrated Circuit (ASIC), a Network Processor (NP), a Field Programmable Gate Array (FPGA), or other programmable logic devices, gate circuits, transistors, discrete hardware components, etc. The receiving and transmitting modules can be implemented by a communication interface, which can include one or more of the following: transceiver, pins, circuits, buses, radio frequency units, etc.

[0196] Specifically, referring to Figure 7, the mobility management device 700 includes:

[0197] The first sending module 701 is used to send a target message to the second network entity when a first condition is met. The target message is used to request the allocation of an evolved packet system EPS bearer identifier (EBI).

[0198] The first condition includes:

[0199] The terminal switches or reselects from the second mobile communication system to the first mobile communication system;

[0200] The protocol data unit (PDU) session corresponding to the first mobile communication system contains a target PDU session that can be switched or reselected to the third mobile communication system.

[0201] The first mobile communication system is a fifth-generation mobile communication system, and the third mobile communication system is a fourth-generation mobile communication system.

[0202] Optionally, the first condition further includes:

[0203] The target PDU session does not have an EBI stored or exists in its context.

[0204] Optionally, the mobility management device 700 also includes:

[0205] A first receiving module is configured to receive a target EBI allocated for the terminal from the second network entity;

[0206] The first sending module 701 is further configured to send the target EBI to the target device;

[0207] The target device includes at least one of a terminal, a third network entity, and an access network device.

[0208] Optionally, the first sending module 701 is specifically configured to perform at least one of the following:

[0209] Send a PDU session modification message to the terminal, wherein the PDU session modification message contains the EBI;

[0210] Send an N4 session modification message to the third network entity, the N4 session modification message containing the EBI;

[0211] The access network device is sent N2 Session Management (SM) information, which includes the EBI.

[0212] Optionally, the first sending module 701 is further configured to send target indication information to the second network entity, the target indication information being used to instruct the terminal to switch or reselect from the second mobile communication system to the first mobile communication system.

[0213] Optionally, the target message includes at least one of the following:

[0214] EBI allocation request message;

[0215] Create an SM context response message.

[0216] Optionally, the second mobile communication system is a sixth-generation mobile communication system or a seventh-generation mobile communication system.

[0217] Specifically, referring to Figure 8, the mobility management device 800 includes:

[0218] The second receiving module 801 is used to receive a target message from the first network entity, the target message being used to request the allocation of an evolved packet system EPS bearer identifier (EBI).

[0219] The target message is triggered based on a first condition, which includes:

[0220] The terminal switches or reselects from the second mobile communication system to the first mobile communication system;

[0221] The protocol data unit (PDU) session corresponding to the first mobile communication system contains a target PDU session that can be switched or reselected to the third mobile communication system.

[0222] The first mobile communication system is a fifth-generation mobile communication system, and the third mobile communication system is a fourth-generation mobile communication system.

[0223] Optionally, the mobility management device 800 also includes:

[0224] The processing module is used to allocate a target EBI to the terminal based on the target message;

[0225] The second sending module is used to send the target EBI to the first network entity.

[0226] Optionally, the mobility management device 800 also includes:

[0227] A processing module for reclaiming the EBI allocated to the terminal.

[0228] Optionally, the processing module is specifically configured to reclaim the EBI allocated to the terminal if it is determined that the second condition is met;

[0229] The second condition includes at least one of the following:

[0230] The second network entity assigns an EBI to the terminal;

[0231] The terminal switches or reselects from the second mobile communication system to the first mobile communication system.

[0232] Optionally, the processing module is further configured to determine whether the terminal switches or reselects from the second mobile communication system to the first mobile communication system based on any one of the following:

[0233] The message received by the second network entity during the switching or reselection of the terminal;

[0234] The target indication information received from the first network entity is used to instruct the terminal to switch or reselect from the second mobile communication system to the first mobile communication system.

[0235] Optionally, the first condition further includes:

[0236] The target PDU session does not have an EBI stored or exists in its context.

[0237] Optionally, the mobility management device 800 also includes:

[0238] The second receiving module is configured to receive target indication information from the first network entity, the target indication information being used to instruct the terminal to switch or reselect from the second mobile communication system to the first mobile communication system.

[0239] Optionally, the target message includes at least one of the following:

[0240] EBI allocation request message;

[0241] Create an SM context response message.

[0242] Optionally, the second mobile communication system is a sixth-generation mobile communication system or a seventh-generation mobile communication system.

[0243] The mobility management device provided in this application embodiment can implement the various processes implemented in the method embodiments of Figures 3 to 6 and achieve the same technical effect. To avoid repetition, it will not be described again here.

[0244] As shown in Figure 9, this application embodiment also provides a communication device 900, including a processor 901 and a memory 902. The memory 902 stores a program or instructions that can run on the processor 901. When the program or instructions are executed by the processor 901, they implement the various steps of the above-described mobile management method embodiment and can achieve the same technical effect. To avoid repetition, they will not be described again here.

[0245] This application also provides a network-side device, including a processor and a communication interface. The communication interface is coupled to the processor, and the processor is used to run programs or instructions to implement the steps of the method embodiments shown in FIG3 or FIG6. This network-side device embodiment corresponds to the above-described network-side device method embodiment. All implementation processes and methods of the above-described method embodiments can be applied to this network-side device embodiment and can achieve the same technical effect.

[0246] Specifically, this application also provides a network-side device. As shown in FIG10, the network-side device 1000 includes a processor 1001, a network interface 1002, and a memory 1003. The network-side device may be the mobility management device shown in FIG7 or FIG8. The network interface 1002 is, for example, a common public radio interface (CPRI).

[0247] When the network-side device is the first network entity, the network interface 1002 is used to send a target message to the second network entity when the first condition is met. The target message is used to request the allocation of an evolved packet system EPS bearer identifier (EBI).

[0248] The first condition includes:

[0249] The terminal switches or reselects from the second mobile communication system to the first mobile communication system;

[0250] The protocol data unit (PDU) session corresponding to the first mobile communication system contains a target PDU session that can be switched or reselected to the third mobile communication system.

[0251] The first mobile communication system is a fifth-generation mobile communication system, and the third mobile communication system is a fourth-generation mobile communication system.

[0252] When the network-side device is the second network entity, the network interface 1002 is used to receive a target message from the first network entity. The target message is used to request the allocation of an evolved packet system EPS bearer identifier (EBI).

[0253] The target message is triggered based on a first condition, which includes:

[0254] The terminal switches or reselects from the second mobile communication system to the first mobile communication system;

[0255] The protocol data unit (PDU) session corresponding to the first mobile communication system contains a target PDU session that can be switched or reselected to the third mobile communication system.

[0256] The first mobile communication system is a fifth-generation mobile communication system, and the third mobile communication system is a fourth-generation mobile communication system.

[0257] In addition, the network-side device 1000 of this application embodiment also includes: a program or instructions stored in the memory 1003 and executable on the processor 1001. The processor 1001 calls the program or instructions in the memory 1003 to execute the methods executed by the modules shown in FIG7 or FIG8 and achieve the same technical effect. To avoid repetition, it will not be described in detail here.

[0258] This application also provides a readable storage medium storing a program or instructions. When the program or instructions are executed by a processor, they implement the various processes of the above-described mobility management method embodiments and achieve the same technical effects. To avoid repetition, they will not be described again here.

[0259] The processor mentioned above is the processor in the network-side device described in the above embodiments. The readable storage medium includes computer-readable storage media, such as computer read-only memory (ROM), random access memory (RAM), magnetic disk, or optical disk. In some examples, the readable storage medium may be a non-transient readable storage medium.

[0260] This application embodiment also provides a chip, which includes a processor and a communication interface. The communication interface is coupled to the processor. The processor is used to run programs or instructions to implement the various processes of the above-described mobile management method embodiments and can achieve the same technical effect. To avoid repetition, it will not be described again here.

[0261] It should be understood that the chip mentioned in the embodiments of this application may also be referred to as a system-on-a-chip, system chip, chip system, or system-on-a-chip, etc.

[0262] This application also provides a computer program / program product, which includes computer instructions. The computer program / program product is executed by at least one processor to implement the various processes of the above-described mobility management method embodiments and can achieve the same technical effect. To avoid repetition, it will not be described again here.

[0263] This application also provides a wireless communication system, including: a first network entity and a second network entity, wherein the first network entity can be used to perform the steps of the mobility management method on the first network entity side as described above, and the second network entity can be used to perform the steps of the mobility management method on the second network entity side as described above.

[0264] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element. Furthermore, it should be noted that the scope of the methods and apparatuses in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

[0265] From the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of computer software products plus necessary general-purpose hardware platforms, and of course, they can also be implemented by hardware. The computer software product is stored in a storage medium (such as ROM, RAM, magnetic disk, optical disk, etc.) and includes several instructions to cause the terminal or network-side device to execute the methods described in the various embodiments of this application.

[0266] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other implementations under the guidance of this application without departing from the spirit and scope of the claims. All of these implementations are within the protection scope of this application.

Claims

1. A mobility management method, comprising: If the first condition is met, the first network entity sends a target message to the second network entity, the target message being used to request the allocation of an evolved packet system EPS bearer identifier (EBI). The first condition includes: The terminal switches or reselects from the second mobile communication system to the first mobile communication system; The protocol data unit (PDU) session corresponding to the first mobile communication system contains a target PDU session that can be switched or reselected to the third mobile communication system. The first mobile communication system is a fifth-generation mobile communication system, and the third mobile communication system is a fourth-generation mobile communication system.

2. The method according to claim 1, wherein, The first condition also includes: The target PDU session does not have an EBI stored or exists in its context.

3. The method according to claim 1 or 2, further comprising: The first network entity receives the target EBI allocated for the terminal from the second network entity; The first network entity sends the target EBI to the target device; The target device includes at least one of a terminal, a third network entity, and an access network device.

4. The method according to claim 3, wherein, The first network entity sends the target EBI to the target device including at least one of the following: The first network entity sends a PDU session modification message to the terminal, the PDU session modification message containing the EBI; The first network entity sends an N4 session modification message to the third network entity, the N4 session modification message containing the EBI; The first network entity sends N2 Session Management (SM) information to the access network device, and the N2 SM information includes the EBI.

5. The method according to any one of claims 1 to 4, further comprising: The first network entity sends target indication information to the second network entity, the target indication information being used to instruct the terminal to switch or reselect from the second mobile communication system to the first mobile communication system.

6. The method according to any one of claims 1 to 5, wherein, The target message includes at least one of the following: EBI allocation request message; Create an SM context response message.

7. The method according to any one of claims 1 to 6, wherein, The second mobile communication system is a sixth-generation mobile communication system or a seventh-generation mobile communication system.

8. A mobility management method, comprising: The second network entity receives a target message from the first network entity, the target message being used to request the allocation of an Evolved Packet System EPS Bearer Identifier (EBI). The target message is triggered based on a first condition, which includes: The terminal switches or reselects from the second mobile communication system to the first mobile communication system; The protocol data unit (PDU) session corresponding to the first mobile communication system contains a target PDU session that can be switched or reselected to the third mobile communication system. The first mobile communication system is a fifth-generation mobile communication system, and the third mobile communication system is a fourth-generation mobile communication system.

9. The method according to claim 8, further comprising: The second network entity allocates a target EBI to the terminal based on the target message; The second network entity sends the target EBI to the first network entity.

10. The method according to claim 8 or 9, further comprising: The second network entity reclaims the EBI allocated to the terminal.

11. The method according to claim 10, wherein, The second network entity reclaims the EBI allocated to the terminal, including: If the second network entity determines that the second condition is met, the second network entity reclaims the EBI allocated to the terminal; The second condition includes at least one of the following: The second network entity assigned an EBI to the terminal; The terminal switches or reselects from the second mobile communication system to the first mobile communication system.

12. The method according to claim 11, further comprising: The second network entity determines whether the terminal switches or reselects from the second mobile communication system to the first mobile communication system based on any of the following: The message received by the second network entity during the switching or reselection of the terminal; The target indication information received from the first network entity is used to instruct the terminal to switch or reselect from the second mobile communication system to the first mobile communication system.

13. The method according to any one of claims 8 to 12, wherein, The first condition also includes: The target PDU session does not have an EBI stored or exists in its context.

14. The method according to any one of claims 8 to 13, wherein the method further comprises: The second network entity receives target indication information from the first network entity, the target indication information being used to instruct the terminal to switch or reselect from the second mobile communication system to the first mobile communication system.

15. The method according to any one of claims 8 to 14, wherein, The target message includes at least one of the following: EBI allocation request message; Create an SM context response message.

16. The method according to any one of claims 8 to 15, wherein, The second mobile communication system is a sixth-generation mobile communication system or a seventh-generation mobile communication system.

17. A mobility management device, comprising: The first sending module is used to send a target message to the second network entity when a first condition is met. The target message is used to request the allocation of an evolved packet system EPS bearer identifier (EBI). The first condition includes: The terminal switches or reselects from the second mobile communication system to the first mobile communication system; The protocol data unit (PDU) session corresponding to the first mobile communication system contains a target PDU session that can be switched or reselected to the third mobile communication system. The first mobile communication system is a fifth-generation mobile communication system, and the third mobile communication system is a fourth-generation mobile communication system.

18. The apparatus according to claim 17, wherein, The first condition also includes: The target PDU session does not have an EBI stored or exists in its context.

19. The apparatus according to claim 17 or 18, further comprising: A first receiving module is configured to receive a target EBI allocated for the terminal from the second network entity; The first sending module is further configured to send the target EBI to the target device; The target device includes at least one of a terminal, a third network entity, and an access network device.

20. A mobility management device, comprising: The second receiving module is used to receive a target message from the first network entity, the target message being used to request the allocation of an Evolved Packet System EPS Bearer Identifier (EBI). The target message is triggered based on a first condition, which includes: The terminal switches or reselects from the second mobile communication system to the first mobile communication system; The protocol data unit (PDU) session corresponding to the first mobile communication system contains a target PDU session that can be switched or reselected to the third mobile communication system. The first mobile communication system is a fifth-generation mobile communication system, and the third mobile communication system is a fourth-generation mobile communication system.

21. The apparatus of claim 20, further comprising: The processing module is used to allocate a target EBI to the terminal based on the target message; The second sending module is used to send the target EBI to the first network entity.

22. A network-side device, comprising a processor and a memory, the memory storing a program or instructions executable on the processor, the program or instructions, when executed by the processor, implementing the steps of the mobility management method as claimed in any one of claims 1 to 16.

23. A readable storage medium storing a program or instructions that, when executed by a processor, implement the steps of the mobility management method as claimed in any one of claims 1 to 16.

24. A computer program product comprising computer instructions that, when executed by a processor, implement the steps of the mobility management method as described in any one of claims 1 to 16.

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