Method of accessing the target cell and device

Abstract

The embodiments of this application disclose a method of accessing a cell and a device, to provide a network slice service area identifier and network slice configuration information to a terminal device, so that the terminal device can access a target cell.The method in the embodiments of this application includes: obtaining, by means of a terminal device, a network slice service area identifier from a service access network device that corresponds to a service cell in which the terminal device is located, wherein the network slice service area identifier is used to indicate an area served by a network slice; determining, by means of the terminal device, a target cell based on network slice configuration information and the network slice service area identifier, wherein the network slice configuration information includes a match between a network slice, an area, and a service; and accessing, by means of the terminal device, the target cell.

Description

1 / 59 “METHOD OF ACCESSING THE TARGET CELL AND DEVICE”

[0001] This application claims priority over Patent Application No. CN201710061634.1, filed with the Chinese Patent Office on January 26, 2017, entitled TARGET CELL ACCESS METHOD AND DEVICE, which is incorporated herein by reference in its entirety. FIELD OF TECHNIQUE

[0002] This application relates to the field of mobile communications and, in particular, to a method of accessing a target cell and a device. BACKGROUND

[0003] A growing number of user cases have notably different demands for network performance. In a fifth-generation (5G) mobile communications system, a network slice (NS) concept is proposed to build a related network architecture.

[0004] Currently, according to the Third Generation Partnership Project (3GPP), the main types of 5G network slices are divided into the following three types: an Enhanced Mobile Broadband (eMBB) service, a Massive Machine Type Communication (mTC) service, and an Ultra-Reliable and Low Latency Communications (URLLC) service. eMBB is essentially intended for a terminal with high requirements for speed and mobility, such as a mobile phone or a multimedia device. mMTC is essentially intended for an Internet of Things device with requirements for large scale, low mobility, and a relatively low speed.URLLCs essentially refer to a type of service or device with strong requirements for latency and reliability, such as the Internet of Vehicles and security information. For example, a mobile phone user might access a network slice of an eMBB type to download at high speed or watch a 4K high-definition video. A sensor device might access a network slice of an mMTC type to transmit a small packet of data and update a system configuration. A user might access... Petition 870250050916, dated 06 / 17 / 2025, page 23 / 112 2 / 59 simultaneously, one or more or all network slices, to satisfy a service requirement and achieve a better user experience.

[0005] A procedure for selecting a network slice is divided into two steps: network slice orientation and network slice association.

[0006] Step 1 (network slice orientation): When a terminal device initiates network connection establishment with a selected public land mobile network (PLMN), a radio access network (RAN) forwards a user establishment request to a network slice selection module of a core network (CN).The module can query information about the terminal device, such as subscription information related to a network slice, a service level agreement (SLA), load information, and a local configuration based on useful information provided by the terminal device, such as a selected PLMN identifier, a terminal device identifier, and information about a CN capacity supported by the terminal device, in order to select an appropriate network slice for the terminal device and allocate an appropriate NSID to the terminal device. The terminal device stores the NSID. Furthermore, the network slice selection module notifies the RAN of configuration information corresponding to a selected network slice entity, such as a corresponding NF identifier, so that the RAN subsequently establishes CP and UP channels between the terminal device and the selected network slice.

[0007] Step 2 (Network Slice Association): After network slice orientation is complete, when the terminal device restarts a network slice connection, for example, when the terminal device needs to initiate a service request due to a service requirement, the RAN selects a corresponding NF based on the NSID stored and reported by the terminal device and the configuration information stored locally by the network slice entity, in order to establish CP and UP connections between the terminal device and a network slice instance that corresponds to the terminal device.

[0008] A current network slice orientation mode is Petition 870250050916, dated 06 / 17 / 2025, page 24 / 112 3 / 59 established based on the assumption that a network can definitively select an appropriate network slice for the terminal device. However, a real-world network slice implementation case is not considered, and some network slices may only be implemented in a local area network. For example, a company establishes a network slice for company employees in an industrial park, specifically to serve company employees. Alternatively, a network slice is implemented in a stadium so that when a user starts a service in the stadium, the user can enjoy a better service, and the service experience can be improved. In this case, when the terminal device moves, a server cell changes, and it is difficult for the terminal device to continue to enjoy a service from the network slice. Consequently, it is difficult to guarantee service continuity and the service experience of the network slice. SUMMARY

[0009] The embodiments of this application provide a method of accessing a target cell and a device, to provide a network slice service area identifier and network slice configuration information to a terminal device, so that the terminal device accesses a target cell.

[0010] With this in mind, a first aspect of the embodiments of the present invention provides a method of accessing the target cell, which includes:

[0011] A terminal device obtains a network slice service area identifier from a service access network device that corresponds to a server cell in which the terminal device is located, where the network slice service area identifier is used to indicate an area served by a network slice. In embodiments of this application, a Tracking Area (TA) identifier may be pre-allocated to each cell, for example, a TA identifier for cell 1 is TA1. Different network slices have different service ranges. For example, network slice 1 needs to cover TA1, TA2, and TA3, network slice 2 needs to cover TA2, TA4, and TA5, and network slice 3 covers only TA6. This is not limited in this document.The terminal device determines a target cell based on network slice configuration information and the network slice service area identifier, where the network slice configuration information includes a match between a slice of... Petition 870250050916, dated 06 / 17 / 2025, page 25 / 112 4 / 59 network, an area and a service. The terminal device accesses the target cell.

[0012] With reference to the first aspect of the present invention, in a first embodiment of the first aspect of the present invention, the method includes: The terminal device obtains network slice configuration information from a network core. Optionally, in some feasible embodiments, the network slice configuration information may be pre-configured in device storage of the terminal device or a storage unit of a Subscriber Identification Module (SIM) card, or the configuration message may be sent to the terminal device using a Non-access Stratum (NAS) message, and the terminal device stores the received network slice configuration information.

[0013] The network core and the terminal device exchange network slice configuration information, and the service access network device and the terminal device exchange the network slice service area identifier, so that the terminal device detects a service area of ​​a network slice.

[0014] With reference to the first implementation of the first aspect of the present invention, in a second implementation of the first aspect of the present invention, the method includes:

[0015] The terminal device sends a request message to the network core, where the request message is used to request network slice configuration information. In some feasible embodiments, the terminal device may establish a network connection with the service access network device, for example, an RRC connection. After the network connection is established, the terminal device may perform uplink and downlink data communication with the service access network device, and perform, using the service access network device, uplink and downlink data communication with a network core that serves the service access network device. The terminal device receives network slice configuration information from the network core.

[0016] The network core and the terminal device exchange the network slice service area identifier, so that the device Petition 870250050916, dated 06 / 17 / 2025, p. 26 / 112 5 / 59 terminal detects a service range of a network slice.

[0017] With reference to the first aspect of the present invention, in a third embodiment of the first aspect of the present invention, the method includes:

[0018] The terminal device sends an indication message to the service access network device, wherein the indication message is used to indicate a requirement for a network slice. The terminal device obtains the network slice service area identifier from the service access network device. In embodiments of this request, the terminal device may first synchronize with the service access network device, for example, perform detection on a primary synchronization signal and a secondary synchronization signal, and perform time domain and frequency domain correction, in order to obtain information such as a corresponding frequency channel number and bandwidth.

[0019] When the terminal device that is using a target service moves, even if the server cell changes, the terminal device can determine the target cell based on the obtained network slice configuration information and the obtained network slice service area identifier, and continue to enjoy the target service in the target cell, so that service continuity is guaranteed.

[0020] A second aspect of the embodiments of the present invention provides a method of accessing the target cell, which includes:

[0021] A service access network device sends a connection indication to a target network device. The connection indication is used to instruct the target network device to connect to a terminal device. In embodiments of this request, the service access network device includes a service access network device, and the target network device includes a service access network device or a network core. When the service access network device is a first service access network device, and the target network device is a second RAN network element, in some feasible embodiments, the service access network device initiates an interface establishment request with the target network device. The interface establishment request includes network slice information and is used to Petition 870250050916, dated 06 / 17 / 2025, page 27 / 112 6 / 59 exchanging configurations on the application sides of two connected service access network devices. The service access network device sends a target network slice service area identifier to the endpoint device, where the target network slice service area identifier is used to indicate a target area, so that the endpoint device determines a target cell based on network slice configuration information and the network slice service area identifier, wherein the network slice configuration information includes a match between a network slice, an area, and a service.

[0022] With reference to the second aspect of the present invention, in a first embodiment of the second aspect of the present invention, the method includes:

[0023] The service access network device sends a handover request to the target network device, wherein the handover request includes the connection indication, used to initiate handover preparation. The fact that the service access network device sends a target network slice service area identifier to the terminal device includes: The service access network device sends a handover command to the terminal device, wherein the handover command includes the target network slice service area identifier, and the handover command instructs the terminal device to handover to the target network device.

[0024] Network devices exchange network slice configuration information, so that a network device detects slice coverage information from a neighboring cell.

[0025] With reference to the second aspect of the present invention, in a second embodiment of the second aspect of the present invention, the method includes:

[0026] The service access network device sends a node addition request to the target network device, wherein the node addition request includes the connection indication. Two network devices may exchange a service area identifier of a network slice that is serving the endpoint device or that is required by the endpoint device, wherein the service access network device may condition the device Petition 870250050916, dated 06 / 17 / 2025, page 28 / 112 7 / 59 of the target network to perform a multiple connection operation or directly modify information about the target network device. The fact that the service access network device sends a target network slice service area identifier to the terminal device includes: The service access network device sends a connection reconfiguration message to the terminal device, where the connection reconfiguration message includes the target network slice service area identifier, and the connection reconfiguration message is used to instruct the terminal device to connect to the target network device.

[0027] Network devices exchange a service area identifier of a network slice that is serving the terminal device or that the terminal device is interested in, so that the target network device can consider the information to optimize mobility.

[0028] With reference to the second aspect of the present invention, in a third embodiment of the second aspect of the present invention, the method includes:

[0029] The service access network device sends a node modification request to the target network device, wherein the node modification request is used to instruct the target network device to modify a radio resource configuration of the target network device for the terminal device. In some feasible embodiments, two network devices may exchange a service area identifier of a network slice that is serving the terminal device or that is required by the terminal device, and a primary service access network device triggers a secondary service access network device to modify a current multi-connection operation. The service access network device sends a connection reconfiguration message to the terminal device, wherein the connection reconfiguration message includes the radio resource configuration.

[0030] Network devices exchange a service area identifier of a network slice that is serving the terminal device or that the terminal device is interested in, so that the service access network triggers the target network device to perform the multi-connection operation or modify the target network device. Petition 870250050916, dated 06 / 17 / 2025, page 29 / 112 8 / 59

[0031] With reference to the second aspect of the present invention, in a fourth embodiment of the second aspect of the present invention, the method includes:

[0032] The service access network device receives a node modification request sent by the target network device. In some feasible embodiments, two network devices may exchange a service area identifier of a network slice that is serving the endpoint device or that is required by the endpoint device, and a secondary service access network device initiates modification of an ongoing multi-connection operation.

[0033] Network devices exchange a service area identifier of a network slice that is serving the terminal device or that the terminal device is interested in, so that a primary service access network device triggers the target network device to modify the current multi-connection operation.

[0034] When the terminal device that is using a target service moves, even if a server cell changes, the terminal device can determine the target cell based on the obtained network slice configuration information and the obtained network slice service area identifier, and continue to enjoy the target service in the target cell, so that continuity of service is guaranteed.

[0035] A third aspect of the embodiments of the present invention provides a terminal device, which includes: A first acquisition module, configured to obtain a network slice service area identifier from a service access network device that corresponds to a server cell in which the terminal device is located, where the network slice service area identifier is used to indicate an area served by a network slice; a determination module, configured to determine a target cell based on network slice configuration information and the network slice service area identifier, where the network slice configuration information includes a match between a network slice, an area, and a service; and an access module, configured to access the target cell.

[0036] With reference to the third aspect of the present invention, Petition 870250050916, dated 06 / 17 / 2025, page 30 / 112 9 / 59 In a first implementation of the third aspect of the present invention, the terminal device includes: a second acquisition module, configured to obtain network slice configuration information from a network core.

[0037] With reference to the third aspect of the present invention, in a second embodiment of the third aspect of the present invention, the terminal device includes: A first transmitter submodule, configured to send a request message to the network core, where the request message is used to request network slice configuration information; and a receiver submodule, configured to receive network slice configuration information from the network core.

[0038] With reference to the third aspect of the present invention, in a third embodiment of the third aspect of the present invention, the terminal device includes: a second transmitter submodule, configured to send an indication message to the service access network device, where the indication message is used to indicate a requirement for a network slice; and a fetch submodule, configured to obtain the network slice service area identifier from the service access network device.

[0039] A fourth aspect of the embodiments of the present invention provides a service access network device, which includes: A first transmitter module, configured to send a connection indication to a target network device. The connection indication is used to instruct the target network device to connect to a terminal device; and a second transmitter module, configured to send a target network slice service area identifier to the terminal device, wherein the target network slice service area identifier is used to indicate a target area, so that the terminal device determines a target cell based on network slice configuration information and the network slice service area identifier, wherein the network slice configuration information includes a match between a network slice, an area, and a service. Petition 870250050916, dated 06 / 17 / 2025, page 31 / 112 10 / 59

[0040] With reference to the fourth aspect of the present invention, in a first embodiment of the fourth aspect of the present invention, the first transmitter module includes: A first transmitter submodule, configured to send a handover request to the target network device, where the handover request includes the connection indication. The second transmitter module includes: a second transmitter submodule, configured to send a handover command to the terminal device, where the handover command includes the target network slice service area identifier, and the handover command instructs the terminal device to transfer via handover to the target network device.

[0041] With reference to the fourth aspect of the present invention, in a second embodiment of the fourth aspect of the present invention, the first transmitter module includes: A third transmitter submodule, configured to send a node addition request to the target network device, where the node addition request includes the connection indication. The second transmitter module includes: a fourth transmitter submodule, configured to send a connection reconfiguration message to the terminal device, where the connection reconfiguration message includes the target network slice service area identifier, and the connection reconfiguration message is used to instruct the terminal device to connect to the target network device.

[0042] With reference to the fourth aspect of the present invention, in a third embodiment of the fourth aspect of the present invention, the service access network device includes: A third transmitter module, configured to send a node modification request to the target network device, wherein the node modification request is used to instruct the target network device to modify a radio resource configuration from the target network device to the terminal device; and a first receiver module, configured to send a connection reconfiguration message to the terminal device, wherein the connection reconfiguration message includes the radio resource configuration. Petition 870250050916, dated 06 / 17 / 2025, page 32 / 112 11 / 59

[0043] With reference to the fourth aspect of the present invention, in a fourth embodiment of the fourth aspect of the present invention, the service access network device includes: a second receiver module, configured to receive a node modification request sent by the target network device.

[0044] A fifth aspect of the embodiments of the present invention provides a terminal device, which includes: A transceiver, a memory, a processor, and a bus. The transceiver, memory, and processor are connected using the bus. The transceiver is configured to obtain a network slice service area identifier from a service access network device that corresponds to a server cell in which the terminal device is located, where the network slice service area identifier is used to indicate an area served by a network slice. The processor is configured to: determine a target cell based on network slice configuration information and the network slice service area identifier, where the network slice configuration information includes a match between a network slice, an area, and a service; and access the target cell. The memory is configured to store a program, a target area, a target service, and the network slice configuration information.

[0045] A sixth aspect of the embodiments of the present invention provides a service access network device, which includes: A transceiver, a memory, a processor, and a bus. The transceiver, memory, and processor are connected using the bus. The transceiver is configured to: send a connection indication to a target network device, where the connection indication is used to instruct the target network device to connect to a terminal device; and send a target network slice service area identifier to the terminal device, where the target network slice service area identifier is used to indicate a target area, so that the terminal device determines a target cell based on network slice configuration information and the network slice service area identifier, where the network slice configuration information includes a match between a network slice, an area, and a service. The memory is configured to store a Petition 870250050916, dated 06 / 17 / 2025, page 33 / 112 12 / 59 program, a target area, a target service, and network slice configuration information. The processor is configured to perform a service access network device function.

[0046] Another aspect of this application provides a computer-readable storage medium. The computer-readable storage medium stores an instruction. When the instruction runs on a computer, the computer executes the method in the preceding aspects.

[0047] Another aspect of this application provides a computer program product that includes an instruction. When the instruction runs on a computer, the computer executes the method in the preceding aspects.

[0048] It can be learned from the preceding technical solutions that the modalities of this request have the following advantages:

[0049] The terminal device obtains the network slice service area identifier from the service access network device that corresponds to the server cell in which the terminal device is located, where the network slice service area identifier is used to indicate the area served by the network slice. The terminal device determines the target cell based on the network slice configuration information and the network slice service area identifier, where the network slice configuration information includes the matching between a network slice, an area, and a service. The terminal device accesses the target cell.Therefore, when the terminal device using the target service moves, even if the server cell changes, the terminal device can determine the target cell based on the obtained network slice configuration information and the obtained network slice service area identifier, and continue to enjoy the target service in the target cell, so that service continuity is guaranteed.

[0050] In addition, the service access network device sends the connection indication to the target network device, where the connection indication is used to instruct the target network device to connect to the terminal device. The service access network device sends the target network slice service area identifier to the terminal device, where the target network slice service area identifier is used to indicate the target area. The terminal device determines the target cell based on the Petition 870250050916, dated 06 / 17 / 2025, page 34 / 112 13 / 59 Network slice configuration information and network slice service area identifier, wherein the network slice configuration information includes the matching between a network slice, an area, and a service. Therefore, when the terminal device using the target service moves, even if the server cell changes, the terminal device can determine the target cell based on the obtained network slice configuration information and the obtained network slice service area identifier, and continue to enjoy the target service in the target cell, so that service continuity is guaranteed. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 is a schematic diagram of a network slice system structure, according to an embodiment of this application;

[0052] Figure 2 is a schematic diagram of one embodiment of a target cell access method, according to one embodiment of this request;

[0053] Figure 2.1 is a schematic diagram of an embodiment of a target cell access method, according to an embodiment of this application;

[0054] Figure 3 is a schematic diagram of another embodiment of a target cell access method, according to an embodiment of this request;

[0055] Figure 4 is a schematic diagram of another embodiment of a target cell access method, according to an embodiment of this request;

[0056] Figure 5 is a schematic diagram of another embodiment of a target cell access method, according to an embodiment of this request;

[0057] Figure 6 is a schematic diagram of another embodiment of a target cell access method, according to an embodiment of this request;

[0058] Figure 7 is a schematic diagram of another embodiment of a target cell access method, according to an embodiment of this request;

[0059] Figure 8 is a schematic diagram of another modality. Petition 870250050916, dated 06 / 17 / 2025, page 35 / 112 14 / 59 of a method for accessing the target cell, according to a modality of this request;

[0060] Figure 9 is a schematic diagram of another embodiment of a target cell access method, according to an embodiment of this request;

[0061] Figure 10 is a schematic diagram of an embodiment of a terminal device 1000, according to an embodiment of this application;

[0062] Figure 11 is a schematic diagram of another embodiment of a terminal device 1000, according to an embodiment of this application;

[0063] Figure 12 is a schematic diagram of another embodiment of a terminal device 1000, according to an embodiment of this application;

[0064] Figure 13 is a schematic diagram of another embodiment of a terminal device 1000, according to an embodiment of this application;

[0065] Figure 14 is a schematic diagram of an embodiment of a 1400 service access network device, according to an embodiment of this application;

[0066] Figure 15 is a schematic diagram of another embodiment of a 1400 service access network device, according to an embodiment of this application;

[0067] Figure 16 is a schematic diagram of another embodiment of a 1400 service access network device, according to an embodiment of this application;

[0068] Figure 17 is a schematic diagram of another embodiment of a 1400 service access network device, according to an embodiment of this application;

[0069] Figure 18 is a schematic diagram of another embodiment of a 1400 service access network device, according to an embodiment of this application;

[0070] Figure 19 is a schematic diagram of another embodiment of a 1900 terminal device, according to an embodiment. Petition 870250050916, dated 06 / 17 / 2025, page 36 / 112 15 / 59 of this request; and

[0071] Figure 20 is a schematic diagram of another embodiment of a 2000 service access network device, according to an embodiment of this application. DETAILED DESCRIPTION

[0072] The embodiments of this application provide a method of accessing a target cell and a device, to provide a network slice service area identifier and network slice configuration information to a terminal device, so that the terminal device accesses a target cell.

[0073] To enable those skilled in the art to better understand the solutions in the embodiments of this application, the following section describes, in a clear and complete manner, the technical solutions in the embodiments of this application with reference to the attached drawings in the embodiments of this application. Obviously, the embodiments described are only some, but not all, of the embodiments of this application.

[0074] In the descriptive report, claims and accompanying drawings of this application, the terms first, second, third, fourth and so forth (if any) are intended to distinguish between similar objects, but do not necessarily indicate a specific order or sequence. It should be understood that the data so named are interchangeable under appropriate circumstances so that embodiments of the present invention, described herein, may be implemented in orders other than the order illustrated or described herein.Furthermore, the terms include, contain, and any other variants are intended to encompass non-exclusive inclusion; for example, a process, method, system, product, or device that includes a list of steps or units is not necessarily limited to those expressly listed steps or units, but may include other steps or units not expressly listed or inherent to such process, method, system, product, or device.

[0075] As shown in Figure 1, Figure 1 is a schematic architectural diagram of a network slice system. The network slice system includes a network device and a terminal, and the network device includes a network core and an access network. A Long Term Evolution (LTE) system is used as an example for the description. Petition 870250050916, dated 06 / 17 / 2025, page 37 / 112 16 / 59 next.

[0076] It should be noted that when a terminal device is located within the coverage area of ​​a cell (a carrier) provided by a macro base station or a micro base station, the terminal device communicates with the network device using a transmission resource (e.g., a frequency domain resource or a spectrum resource) used by the cell. The cell may be a cell corresponding to the network device, and the cell may belong to a macro cell, a hyper cell, or a beam, or it may belong to a base station that corresponds to a small cell. The small cell may include, in this document, a metro cell, a micro cell, a pico cell, a femto cell, or similar. The small cell includes a small coverage area and low transmission power, and is applicable for providing a high-rate data transmission service.When there is a plurality of cells serving the terminal device, the terminal device can operate in a coordinated multiple point transmission (CoMP) mode.

[0077] In one embodiment of this application, a network slice system function is deployed using a software-defined network (SDN) technology and a network function virtualization (NFV) technology as core technologies.

[0078] NFV technology deploys virtualization of an underlying physical resource and loads a virtual network function (NF) onto a general platform, such as a virtual machine. SDN technology deploys a logical connection between virtual machines and builds a path that carries signaling and a data stream. An end-to-end service link is configured using dynamic connections between different NFs of a radio access network (RAN) and a core network (CN), so that a network slice is built. Based on specific business use case requirements for key performance indicators (KPIs), such as capacity, coverage, rate, latency, and reliability, an operator can form Petition 870250050916, dated 06 / 17 / 2025, page 38 / 112 17 / 59 a specific set of network functions and network resources required to perform those network functions, so that a necessary telecommunications service and network capacity service can be provided, thereby satisfying a specific market scenario and requirement.

[0079] It should be noted that in 3GPP, current discussions regarding network architecture focus essentially on network slice selection. Network slice selection aims to select an appropriate network slice for user equipment (UE) and associate the terminal device with a specific network slice, so as to establish a corresponding control plane (CP) and / or user plane (UP) connection with the network slice.

[0080] In some feasible embodiments, when the terminal device needs to be associated with a network slice or transfer a network slice by handover, an appropriate network slice can be selected and associated with the terminal device based on network slice orientation, i.e., a corresponding network slice identification (NSID) is allocated to the terminal device. Specifically, the NSID is selected for the terminal device in two network slice orientation modes, in order to deploy a network slice selection completion procedure.

[0081] Guidance mode 1: A network slice identification (NSID) is pre-configured on a universal subscriber identity module (USIM) card of the terminal device. Guidance mode 2: In a process where the terminal device aligns with a public land mobile network (PLMN), a network allocates an NSID to the terminal device.

[0082] The two modes correspond, respectively, to different scenarios. After network slice orientation is complete, the terminal device stores an NSID for each PLMN, and uses the NSID in the subsequent communication process with the PLMN, and the NSID is used by the network to associate the terminal device with a corresponding network slice.

[0083] This request is used to solve a problem of how a service access network device considers network slice implementation and the mobility of an endpoint device. That is, for a slice of Petition 870250050916, dated 06 / 17 / 2025, page 39 / 112 18 / 59 In a network restricted by a service area, the mobility of the terminal device is considered. When the terminal device moves, the continuity of service from the network slice to the terminal device is improved. Specifically, a terminal device, in an idle state, learns information about the coverage area of ​​a required network slice, so that the terminal device can increase a priority to select or reselect cells covered by the required network slice, to access those cells as much as possible.Furthermore, when the terminal device has accessed the network slice and moves to a spanning edge of a current cell, and a handover needs to be performed between a source cell and a target cell, a source service access network device needs to select an appropriate target service access network device to ensure that the target service access network device can provide a service from the network slice accessed by the terminal device, or reselect another network slice and ensure that a handover procedure is successfully performed.

[0084] In some feasible embodiments, this application is also applicable to a Universal Mobile Telecommunications System (UMTS), a CDMA system, a wireless local area network (WLAN), or a future 5G wireless communications system, such as a New Radio (NR) or evolved LTE (eLTE) system of a New Radio Access Technology. That is, an access network device in eLTE can simultaneously connect to an LTE network core, a future 5G network core, and the like.

[0085] In the embodiments of this application, the network device may be a device that is on an access network and that communicates with and connects to a terminal via an air interface using a sector. The network device may be configured to mutually convert a frame received over the air and an Internet Protocol (IP) packet, and act as a router between the terminal device and a remnant part of the access network. The remnant part of the access network may include an IP network. The network device may additionally coordinate attribute management of the air interface. For example, the network device may be a workstation. Petition 870250050916, dated 06 / 17 / 2025, page 40 / 112 19 / 59 base transceiver (Base Transceiver Station, BTS) in a Global System for Mobile Communication (GSM) or Code Division Multiple Access (CDMA) technology; or it may be a NodeB (NodeB) in Wideband Code Division Multiple Access (WCDMA); or it may be an evolved NodeB (NodeB, eNB or e-NodeB, evolutional Node B) in LTE. This is not limited to what is covered in this document.

[0086] In the embodiments of this application, a RAN device may be an Access Point (AP) in WLAN or a Base Transceiver Station (BTS) in GSM or CDMA; or it may be a NodeB (NB) in WCDMA; or it may be an Evolutional Node B (eNB or eNodeB) in LTE, a relay station or an access point, an in-vehicle device, a body-worn device, a network device in a future 5G network or a network device in a future evolved PLMN network, for example, a base station, a Transmission and Reception Point (TRP), a centralized unit (CU) or a distributed unit (DU) that can connect to a 5G network core device.A network connectivity (NC) device can be a Mobile Management Entity (MME) or a gateway in LTE, or it can be a Control Plane (CP) or User Plane (UP) network function in the 5G network, for example, a Common Control Plane Network Function (CCNF) or a Session Management Network Function (SMF). The service access network device can be a server, which can vary considerably due to different configurations or performance, and may include one or more central processing units (CPUs) (e.g., one or more processors) and memory, and one or more storage media (e.g., one or more mass storage devices) for storing application programs or data.Memory and storage media can be either transient storage or persistent storage. A program stored on the storage media can include one or more modules (not shown in the figure), and each module can... Petition 870250050916, dated 06 / 17 / 2025, page 41 / 112 20 / 59 include a series of instruction operations for a server. Additionally, the central processing unit can be configured to communicate with the storage media, in order to perform, on the server, a series of instruction operations on the storage media.

[0087] The server may additionally include one or more power supplies, one or more wired or wireless network interfaces, one or more input / output interfaces and / or one or more operating systems, such as Windows Server™, Mac OS X™, Unix™, Linux™ or FreeBSD™.

[0088] In particular, it should be noted that the terminal device mentioned in the embodiments of this application may be a device that provides a user with voice and / or data connectivity, a handheld device with a radio connection function, or another processing device connected to a wireless modem. A wireless terminal may communicate with a network core via a radio access network (RAN). The wireless terminal may be a mobile terminal, such as a mobile phone (or so-called cellular phone), and a computer with a mobile terminal, for example, may be a portable, pocket-sized, handheld device, embedded in a computer, or a mobile device inside a vehicle, which exchanges voice and / or data with the radio access network.For example, a wireless terminal can be a device, such as a Personal Communication Service (PCS) phone, a cordless phone, a Session Initiation Protocol (SIP) phone, a Wireless Local Loop (WLL) station, or a Personal Digital Assistant (PDA). A wireless terminal can also be referred to as a system, a subscriber unit, a subscriber station, a mobile station, a remote station, an access point, a remote terminal, an access terminal, a user terminal, a terminal device, a user agent, a user device, or user equipment.

[0089] A mobile phone is used as an example, and a mobile phone structure may include components such as a radio frequency (RF) circuit, a memory, an input unit, Petition 870250050916, dated 06 / 17 / 2025, page 42 / 112 21 / 59 a display unit, a sensor, an audio frequency circuit, a wireless fidelity (WiFi) module, a processor, and a power supply. Those skilled in the art may understand that the mobile phone structure shown in Figure 11 does not constitute a limitation on the mobile phone, and the mobile phone may include more or fewer components than those shown in the figure, or combine some components, or have different component arrangements.

[0090] In embodiments of this application, the terminal device obtains a network slice service area identifier from a service access network device that corresponds to a server cell in which the terminal device is located, wherein the network slice service area identifier is used to indicate an area served by a network slice. The terminal device determines a target cell based on network slice configuration information and the network slice service area identifier, wherein the network slice configuration information includes a match between a network slice, an area, and a service. The terminal device accesses the target cell.Therefore, when the terminal device using a target service moves, even if the server cell changes, the terminal device can determine the target cell based on the obtained network slice configuration information and the obtained network slice service area identifier, and continue to enjoy the target service in the target cell, so that service continuity is guaranteed.

[0091] In addition, the service access network device sends a connection indication to the target network device, wherein the connection indication is used to instruct the target network device to connect to the terminal device. The service access network device sends a target network slice service area identifier to the terminal device, wherein the target network slice service area identifier is used to indicate a target area, so that the terminal device determines the target network device based on the target area, target service, and pre-obtained network slice configuration information, and accesses a target cell served by a target network. Therefore, when the terminal device using the target service moves, even if the serving cell changes, the terminal device can determine the target cell based on the information of Petition 870250050916, dated 06 / 17 / 2025, page 43 / 112 22 / 59 network slice configuration obtained and in the network slice service area identifier obtained, and continue to enjoy the target service in the target cell, so that service continuity is guaranteed.

[0092] To facilitate understanding, the following section describes a specific procedure in the modalities of this application. The terminal device obtains network slice information in different ways, and the ways are described separately below.

[0093] I. The terminal device obtains, separately, related information from a network core and from a service access network device.

[0094] Referring to Figure 2, one embodiment of a target cell access method, in one embodiment of this application, includes the following steps.

[0095] 201. The terminal device obtains a network slice service area identifier from a service access network device that corresponds to a server cell in which the terminal device is located, where the network slice service area identifier is used to indicate an area served by a network slice.

[0096] In some feasible embodiments, the service access network device may additionally send network slice service area identifier information to the terminal device. It should be noted that the network slice service area identifier stored by the service access network device may be pre-configured by a network management system, such as an Operation and Management (OAM) entity, or it may be pre-configured by an application layer role entity. This is not limited to this document. It should be noted that the terminal device may obtain one or more network slice service area identifiers. This is not limited to this document.

[0097] Additionally, in some feasible embodiments, network slice service area identification information may be a system message sent using a Radio Resource Control (RRC) message, and the system message may be included in an existing system message block as a Petition 870250050916, dated 06 / 17 / 2025, page 44 / 112 23 / 59 newly added field, or it can be used as a new system message block and sent to the terminal device. This is not limited in this document. The network slice service area identification information can alternatively be a dedicated message to the terminal device sent using an RRC message, and only the terminal device can correctly receive and decode the message, so that another terminal device cannot receive the message in this case.

[0098] Additionally, in some feasible embodiments, at least one network slice identifier included in the network slice service area identifier information may be classified based on a priority, that is, a network slice service area priority. The network slice service area priority is used to indicate a priority that corresponds to the network slice service area identifier, for example, a priority of a network slice service area A is higher than that of a network slice service area B.

[0099] Additionally, in some feasible embodiments, the network slice service area identifier may indicate a coverage area of ​​a network slice, and the network slice may encompass a group of cells in a PLMN. Each cell may belong to one or more network slice service areas. The network slice service area identifier may further indicate that the network slice encompasses all cells throughout the PLMN.

[0100] Additionally, the network slice service area identifier can be a specific predefined value, or it can be a group of cell identifiers, a group of service access network device identifiers, or a list of tracking area (TA) identifiers.

[0101] Additionally, in some feasible embodiments, after receiving the network slice service area identifier, the terminal device can determine a coverage area of ​​a network slice that corresponds to the identifier, and can determine a service or a type of service that can be provided by the network slice.

[0102] Additionally, in some feasible modalities, the Petition 870250050916, dated 06 / 17 / 2025, page 45 / 112 24 / 59 Network slice service area identification information includes, but is not limited to, the following related information: information about a frequency channel number for each frequency in the same frequency list or different frequency lists supported by a cell; and a network slice service area identifier supported by the frequency channel number, where the network slice service area identifier is used to uniquely identify a network slice service area, and the area may be a sector, a beam, a cell, a scan area, a paging area, a service access network device station, a Transmission and Reception Point (TRP), a Distributed Unit (DU), a Central Unit (CU), or similar. This is not limited in this document.

[0103] In some feasible embodiments, information about a frequency channel number for each frequency in the same frequency list or different frequency lists supported by a neighboring cell and a network slice service area identifier supported by the frequency channel number are used to uniquely identify a network slice service area. The area may be a sector, a beam, a cell, a trace area, a paging area, a service access network device station, a TRP, a DU, a CU, or similar. This is not limited to in this document.

[0104] Note that there may be many split cells of a service access network device. For example, a base station has many antennas, and each antenna may form a sector-shaped cell. A cell that the terminal device accesses and information about the cell are included in this document.

[0105] 202. The terminal device determines a target cell based on network slice configuration information and the network slice service area identifier, wherein the network slice configuration information includes a match between a network slice, an area, and a service.

[0106] In some feasible embodiments, the terminal device may use the received network slice configuration information and the received network slice service area identification information as Petition 870250050916, dated 06 / 17 / 2025, page 46 / 112 25 / 59 a pattern for cell selection and re-selection. Additionally, for a terminal device that is being served by the service, by the service type and / or by the network slice, the terminal device may specify, for higher priority, an identifier of a current parking cell that may provide the service and / or a frequency and frequency channel number of the current parking cell. When performing cell re-selection, the terminal device may preferentially re-select a cell that matches the cell identifier and / or a cell that matches the frequency and frequency channel number.

[0107] Additionally, for a terminal device that needs to be served by the service, by the service type and / or by the network slice, when the terminal device expects to be served by the service, by the service type and / or by the network slice, the terminal device may specify, for a higher priority, an identifier of a current parking cell that can improve the service and / or a frequency and frequency channel number of the current parking cell. When performing cell reselection, the terminal device may preferentially reselect a cell that matches the frequency and cell identifier and / or a cell that matches the frequency channel number.

[0108] Additionally, when there is no service, service type and / or network slice required by the terminal device, for example, a session termination, the terminal device no longer specifies, for the highest priority, the frequency and frequency channel number of the current parking cell that can improve the service.

[0109] 203. The terminal device accesses the target cell.

[0110] 204. The terminal device obtains network slice configuration information from the network core.

[0111] Optionally, referring to Figure 2.1, this modality may additionally include step 204, and step 204 is performed before step 201.

[0112] In this type of request, a Tracking Area (TA) identifier can be pre-allocated to each cell, for example, a TA identifier for cell 1 is TA1. Different network slices have different service ranges. For example, network slice 1 Petition 870250050916, dated 06 / 17 / 2025, page 47 / 112 26 / 59 needs to cover TA1, TA2, and TA3; a network slice 2 needs to cover TA2, TA4, and TA5; and a network slice 3 covers only TA6. This is not limited in this document.

[0113] In this embodiment of this request, the terminal device may receive network slice configuration information sent by the network core or a function entity related to an application layer or a service layer, wherein the network slice configuration information includes a correspondence between a network slice and a service. Specifically, for example, the network slice configuration information indicates that network slice 1 may provide service 1, service 2, and service 3, and network slice 2 may provide service 3, service 4, and service 5.

[0114] Optionally, in some feasible embodiments, network slice configuration information may be pre-configured in device storage of the terminal device or a storage unit of a Subscriber Identification Module (SIM) card, or the configuration message may be sent to the terminal device using a Non-access (NAS) stratum message, and the terminal device stores the received network slice configuration information.

[0115] Additionally, in some feasible embodiments, network slice configuration information may include, but is not limited to, the following related information: a service, for example, a video, a sports program or a television channel, or a type of service corresponding to one or more services, for example, an identifier corresponding to a video type service, such as a Temporary Mobile Group Identity (TMGI), used to indicate the service, channel or type of service; a time at which a session corresponding to a service or type of service starts and / or ends, used to indicate a time at which the service starts or ends; frequency information corresponding to a service or type of service, used to indicate a frequency or frequency channel number only or at least at which the service or type of service can provide a service;a network slice service area identifier that; Petition 870250050916, dated 06 / 17 / 2025, page 48 / 112 27 / 59 corresponds to a service or a type of service, where the service may correspond to one or more network slice service area identifiers, and the service may only be used in cells that correspond to the network slice service area identifiers; network slice identification information that corresponds to a service or a type of service; and a network slice identifier that is allocated to a network slice and indicated by the network slice identification information.

[0116] Network slice identification information that corresponds to a service or a service type may include, but is not limited to: a network slice type, such as information indicating a network slice type, for example, Enhanced Mobile Broadband (eMBB), Ultra-Reliable Low Latency Communications (URLLC) or Massive Machine Type Communication (mTC), wherein the network slice type may additionally be an end-to-end network slice type, which includes a RAN and CN, or may be a service access network device network slice type, or a network core network slice type; a service type, relating to a specific service, such as information indicating a service feature or a specific service, for example, a video service, an Internet for Vehicles service or a voice service;Tenant information, used to indicate information about a customer that establishes or rents a network slice, for example, Tencent or State Grid; Endpoint device group information, used to indicate information about a group in which a user is grouped based on a resource, such as a user level; Slice group information, used to indicate an instance identifier that the endpoint device can access based on a resource, or used to indicate an instance identifier and resource information, for example, an identifier is allocated to a network slice instance and is used to identify the network slice instance, or a new identifier is mapped based on a network slice instance identifier, the identifier is associated with the network slice instance, and a receiver can identify a specific network slice instance represented based on the identifier;and a dedicated core network (DCN) identifier; Petition 870250050916, dated 06 / 17 / 2025, page 49 / 112 28 / 59 where the identifier is used to exclusively indicate a dedicated network core, for example, a dedicated Internet of Things network core, and optionally, there may be a mapping relationship between a DCN identifier and a network slice identifier, the network slice identifier may be obtained based on the mapped DCN identifier, and the DCN identifier may be obtained based on the mapped network slice identifier. In some feasible embodiments, the network slice configuration information may additionally include other required information. This is not limited to in this document.

[0117] It should be noted that, after receiving the network slice configuration information, the terminal device can store the network slice configuration information and synchronize with a connected service access network device, for example, performing detection on a primary synchronization signal and a secondary synchronization signal, and performing correction in the time domain and frequency domain, in order to obtain information such as a corresponding frequency channel number and bandwidth. In other words, the terminal device synchronizes with the service access network device in both the time domain and the frequency domain. For example, when a base station needs to send information, the terminal device needs to obtain a precise moment when the information is sent. In some feasible embodiments, the terminal device needs to synchronize with the RAN before the terminal device initiates communication with the RAN.

[0118] II. The terminal device obtains related information from a network core.

[0119] 301. The terminal device sends a request message to the network core, where the request message is used to request network slice configuration information.

[0120] In some feasible embodiments, the terminal device may establish a network connection with a service access network device, for example, an RRC connection. After the network connection is established, the terminal device may perform uplink and downlink data communication with the service access network device, and perform, using the service access network device, Petition 870250050916, dated 06 / 17 / 2025, page 50 / 112 29 / 59 uplink and downlink data communication with a network core serving the service access network device.

[0121] Optionally, in some feasible embodiments, the terminal device sends the request message to the network core. In some feasible embodiments, the message may be a NAS message, for example: an attachment request, used to request the terminal device to join or align with the CN; a service request, used to request the terminal device to establish a service with the CN; a session establishment request, used to request the terminal device to establish a session with the CN; or a tracking area update request, used to request the terminal device and the CN to update a tracking area when the terminal device moves out of a current tracking area.

[0122] In some feasible embodiments, the request message may be an RRC message, for example: an RRC connection definition request, used to request the establishment of an RRC connection with a network element of the service access network device; an RRC connection re-establishment request, used to request the re-establishment of an RRC connection with a network element of the service access network device; RRC connection setup completion, used to indicate that a process of establishing an RRC connection with a network element of the service access network device is complete; or terminal device capability information transmission, used to notify the service access network device of terminal device capability information. This is not limited to in this document.

[0123] Additionally, the request message may include, but is not limited to, the following information: a temporary terminal device identifier, allocated to the terminal device by the network core, and used to uniquely identify the terminal device connected to the network element; a service access network device identifier, used to identify the service access network device in a globally unique way; a cell identifier, used to identify the cell. Petition 870250050916, dated 06 / 17 / 2025, page 51 / 112 30 / 59 in a globally unique manner; a network slice identifier; or a request for network slice service area identifier information, used to request the network core to deliver a network slice service area identifier supported by the service access network device and / or cell. In some feasible embodiments, the request message is not limited to the preceding messages, and is not limited in this document.

[0124] 302. The terminal device receives network slice configuration information from the network core.

[0125] In some feasible embodiments, the network core may respond to the terminal device with a message, and the message includes network slice information. Additionally, the message may be a NAS message, for example: attachment permission, used to indicate that the CN grants the attachment request from the terminal device; service request permission, used to indicate that the CN grants the service request from the terminal device; or session establishment, used to indicate that the CN establishes a session for the terminal device.

[0126] Additionally, the message includes, but is not limited to, the following information: a service access network device identifier, used to identify the service access network device in a globally unique manner; or network slice service area identification information supported by a server cell and a neighboring cell, such as network slice service area identification information supported in a list of all frequencies or frequency channel numbers supported by the server cell and the neighboring cell. In some feasible embodiments, the message may additionally include other required information. This is not limited in this document. The terminal device may store the received network slice information, and the network slice information includes the network slice service area identification information.

[0127] 303. The terminal device determines a target cell based on network slice configuration information and a network slice service area identifier, wherein the network slice configuration information includes a match between a network slice, an area and Petition 870250050916, dated 06 / 17 / 2025, page 52 / 112 31 / 59 a service.

[0128] 304. The terminal device accesses the target cell.

[0129] In this mode, steps 303 and 304 are the same as steps 203 and 204 in the previous mode, and the details are not described in this document.

[0130] III. The terminal device obtains related information from a service access network device.

[0131] 401. The terminal device sends an indication message to the service access network device, where the indication message is used to indicate a requirement for a network slice.

[0132] In this aspect, the terminal device can notify the service access network device of a network slice requirement, so that the service access network device detects the terminal device's requirement for the network slice, in order to improve mobility.

[0133] In this embodiment of this application, the terminal device may first synchronize with the service access network device, for example, perform detection on a primary synchronization signal and a secondary synchronization signal, and perform correction in the time domain and frequency domain, in order to obtain information such as a corresponding frequency channel number and bandwidth.

[0134] Then, the terminal device sends the indication message to the service access network device to indicate information about the terminal device's requirement for the network slice. Additionally, the message can be sent using a random access resource, such as a specific random access preamble or a specific random access time-frequency resource. The message can alternatively be a MAC control element message, and the message can be an RRC message, for example: an RRC connection setup request, used to request the establishment of an RRC connection with a network element of the service access network device; an RRC connection re-establishment request, used to request the re-establishment of an RRC connection with a network element of the service access network device; completion of Petition 870250050916, dated 06 / 17 / 2025, page 53 / 112 32 / 59 RRC connection definition, used to indicate that a process of establishing an RRC connection with a network element of the service access network device is complete; or terminal device capability information transmission, used to notify the service access network device of terminal device capability information. This is not limited to the scope of this document.

[0135] Additionally, the indication message may include, but is not limited to, the following messages: a service area identifier of a network slice that is serving the terminal device; information about a frequency or frequency channel number that corresponds to the service area identifier of the network slice that is serving the terminal device; a service area identifier of a network slice required by the terminal device; information about a frequency or frequency channel number that corresponds to the service area identifier of the network slice required by the terminal device; and a network slice service area priority, used to indicate a priority that corresponds to a network slice service area identifier, for example, a priority of network slice A is higher than that of network slice B.

[0136] In this embodiment of this application, the service access network device may store the indication information. Optionally, a network element on one side of the access network may obtain, for handover preparation, information about a capacity requirement of the terminal device by the network slice. This is not limited in this document.

[0137] 402. The terminal device obtains a network slice service area identifier from a service access network device that corresponds to a server cell in which the terminal device is located, where the network slice service area identifier is used to indicate an area served by a network slice.

[0138] 403. The terminal device determines a target cell based on network slice configuration information and the network slice service area identifier, wherein the network slice configuration information includes a match between a network slice, an area, and a service.

[0139] 404. The terminal device accesses the target cell. Petition 870250050916, dated 06 / 17 / 2025, page 54 / 112 33 / 59

[0140] In this mode, steps 402 to 404 are the same as steps 202 to 204 in the previous mode, and the details are not described in this document.

[0141] The preceding section describes separately different embodiments of a method for obtaining network slice information by a terminal device in the embodiments of the present invention, and the following section describes an exchange of network slice information between network devices in the embodiments of the present invention. The network devices exchange network slice information in different ways, and the ways are described separately below.

[0142] 1. A service access network device sends network slice information to a target network device.

[0143] In embodiments of this application, two service access network devices can exchange network slice information, such that a first service access network device learns about slice coverage information from a second service access network device. Referring to Figure 5, another embodiment of a target cell access method, in an embodiment of this application, includes the following steps.

[0144] 501. The service access network device sends a connection indication to the target network device, where the connection indication is used to instruct the target network device to connect to a terminal device.

[0145] In this embodiment of this request, the service access network device includes a service access network device, and the target network device includes a service access network device or a network core. When the service access network device is the first service access network device, and the target network device is a second RAN network element, in some feasible embodiments, the service access network device initiates an interface establishment request to the target network device. The interface establishment request includes network slice information and is used to exchange configurations on the application sides of two connected service access network devices. Additionally, the message includes, but without Petition 870250050916, dated 06 / 17 / 2025, page 55 / 112 34 / 59 limitation, the following information: a service access network device identifier, used to identify the service access network device in a globally unique way; information about a server cell and a neighboring cell of each server cell, for example, cell identifiers, physical cell identifiers, frequency channel number information, tracking area codes, and supported network slice service area identification information that corresponds, respectively, to the server cell and the neighboring cell of each server cell; or a network slice service area priority, used to indicate a priority that corresponds to a network slice service area identifier, for example, a priority of a network slice service area A is higher than that of a network slice service area B.

[0146] 502. The target network device can send an interface establishment request response to the service access network device, to exchange configurations on the application sides of two connected service access network devices.

[0147] Additionally, the message includes, but is not limited to, the following information: a service access network device identifier, used to identify the service access network device in a globally unique manner; information about a server cell and a neighboring cell of each server cell, for example, cell identifiers, physical cell identifiers, frequency channel number information, tracking area codes, and supported network slice service area identification information that corresponds, respectively, to the server cell and the neighboring cell of each server cell; or a network slice service area priority, used to indicate a priority that corresponds to a network slice service area identifier, for example, a priority of a network slice service area A is higher than that of a network slice service area B.

[0148] 503. The service access network device initiates an interface configuration update with the target network device, to transmit updated information.

[0149] Additionally, the message includes, but is not limited to, the following information: a network access device identifier of Petition 870250050916, dated 06 / 17 / 2025, page 56 / 112 35 / 59 service, used to identify the service access network device in a globally unique way; change information about a server cell and a neighboring cell of each server cell, used to perform an operation, such as adding a new cell, modifying an existing cell configuration, or deleting a cell, for example, cell identifiers, physical cell identifiers, frequency channel number information, tracking area codes, and supported network slice service area identification information that correspond, respectively, to the server cell and the neighboring cell of each server cell; or a network slice service area priority, used to indicate a priority that corresponds to a network slice service area identifier, for example, a priority of a network slice service area A is higher than that of a network slice service area B.

[0150] 504. The target network device initiates an interface configuration update confirmation message with the service access network device, to confirm that a configuration update message from the service access network device has been received.

[0151] Optionally, if the target network device cannot support interface configuration update content initiated by the service access network device, the target network device may respond with a failure message, to indicate that a configuration update from the service access network device failed.

[0152] After obtaining the network slice information, the terminal device determines a target network slice based on a target area, a target service, and the network slice information, and the target network slice is used to port the target service in the target area. When the terminal device is located in the target area and uses the target service, the terminal device is associated with the target network slice.

[0153] II. A service access network device sends a handover request to a target network device.

[0154] In one embodiment of this application, in a handover process, the service access network device and the target network device may exchange a service area identifier of a network slice that is serving a terminal device or that is required by a device. Petition 870250050916, dated 06 / 17 / 2025, page 57 / 112 36 / 59 terminal. A target service access network device may consider the information to optimize mobility. For example, in a handover preparation phase, a target RAN device preferably uses, as a new target RAN device after the handover, a network device that matches the service area identifier of the network slice serving the terminal device or that is required by the terminal device. Referring to Figure 6, another embodiment of a target cell access method, in one embodiment of this application, includes the following steps.

[0155] 601. The service access network device sends a handover request to the target network device. The handover request includes a connection indication.

[0156] The service access network device can send the handover request to the target network device to initiate handover preparation. Additionally, the message includes, but is not limited to, the following information: Service area identification information for a network slice that is serving the terminal device; Service area identification information for a network slice required by the terminal device; A network slice service area priority, used to indicate a priority that corresponds to a network slice service area identifier, for example, a priority of network slice service area A is higher than that of network slice service area B; A cause for handover, used to indicate a reason for handover this time, for example, a cause in a radio network layer (such as a handover triggered by a resource or signal optimization); A target cell identifier, used to uniquely indicate the identifier of a target cell; a list of handover restrictions, which includes a server PLMN, an equivalent PLMN, a list of prohibited or permitted tracking areas, a list of prohibited or permitted cells, or similar; A temporary identifier that corresponds to the terminal device, used by a network core to look up a stored context of the terminal device; Petition 870250050916, dated 06 / 17 / 2025, page 58 / 112 37 / 59 an identifier of a network core control function entity associated with the terminal device; a network slice identifier that corresponds to one or more or all of the network slices selected by the terminal device; information about a carrier that needs to be established and that corresponds to one or more or all of the network slices selected by the terminal device, for example, a carrier identifier, a carrier-level QoS (quality of service) parameter, a tunnel endpoint, or carrier-level security information, for example, an encryption function enablement option, where an encryption function location is on the service access network device and / or the network core, a header compression function enablement option, where a header compression function location is on the service access network device and / or the network core, or an integrity protection enablement option, where an integrity protection location is on the service access network device and / or the network core; Session information that needs to be established and that corresponds to one or more or all of the network slices selected by the terminal device, for example, a session identifier, a session-level QoS (quality of service) parameter, a tunnel endpoint, or session-level security information, for example, an encryption function enablement option, where an encryption function is located on the service access network device and / or the network core, a header compression function enablement option, where a header compression function is located on the service access network device and / or the network core, or an integrity protection enablement option, where an integrity protection function is located on the service access network device and / or the network core; Flow information that needs to be established and that corresponds to one or more or all of the network slices selected by the terminal device, for example, a flow identifier, a flow-level QoS (quality of service) parameter, a tunnel endpoint, or flow-level security information, for example, an option of Petition 870250050916, dated 06 / 17 / 2025, page 59 / 112 38 / 59 enabling encryption function, wherein a location of an encryption function is on the service access network device and / or the network core, an enabling header compression function option, wherein a location of a header compression function is on the service access network device and / or the network core, or an enabling integrity protection option, wherein an integrity protection location is on the service access network device and / or the network core; or endpoint device context information, for example, a network slice identifier that corresponds to one or more or all network slices signed by the endpoint device that is not limited in this document.

[0157] 602. The target network device responds to the service access network device with handover request confirmation, to indicate that the target network device has prepared resources.

[0158] Additionally, the message includes, but is not limited to, the following information: an old service access network device identifier; a new service access network device identifier; A transparent container from a target node to a source node, which includes an RRC handover command; A network slice service area identifier, a list of a carrier, session, and / or flow that is / are not allowed, and the network slice service area identifier, carrier, session, and / or flow correspond(s) to one or more or all of the network slices selected by the terminal device; or information about a carrier, session, and / or flow that is allowed, and the carrier, session, and / or flow correspond(s) to one or more or all of the network slices selected by the terminal device, for example, a carrier identifier, a session identifier, a flow identifier, a carrier-level QoS (quality of service) parameter, or a tunnel endpoint that is not limited in this document.

[0159] 603. The service access network device sends a handover command to the terminal device. The handover command includes Petition 870250050916, dated 06 / 17 / 2025, pp. 60 / 112 39 / 59 is a target network slice service area identifier. The handover command instructs the terminal device to transfer via handover to the target network device.

[0160] The service access network device can initiate an RRC message with the terminal device to carry the handover command. Additionally, the message includes, but is not limited to, the following information: network slice service area identification information supported by the target cell; the target cell identifier; a new temporary terminal device identifier; or a carrier configuration, for example, a configuration in a PDCP, a Radio Link Control (RLC) protocol, Media Access Control (MAC), and a physical layer.

[0161] The terminal device establishes an RRC connection with the target network device, and then initiates a handover completion message, such as RRC Connection Reconfiguration Complete, with the target network device, to indicate that the handover is complete.

[0162] Optionally, in some feasible embodiments, when a handover process that uses an interface between a RAN device and a CN device needs to be conditioned, for example, when there is no direct landline interface or no wireless backhaul link between the service access network device and the target network device, the service access network device may additionally initiate a handover request with the CN device. For specific message content, see the handover request message in step 601, where the message is used to initiate handover preparation. The CN device forwards the received message to the target network device, and the target network device responds to the CN device with handover request confirmation, to indicate that the target network device has prepared the resources.For specific message content, refer to the handover request confirmation message in step 602. Then, the CN device forwards the received message to the service access network device.

[0163] II. A service access network device sends a Petition 870250050916, dated 06 / 17 / 2025, pp. 61 / 112 40 / 59 request to add a node to a target network device.

[0164] In one embodiment of this application, two network devices can exchange a service area identifier of a network slice that is serving a terminal device or that is required by a terminal device, wherein the service access network device can condition the target network device to perform a multi-connection operation or directly modify information about the target network device. Referring to Figure 7, another embodiment of a target cell access method, in one embodiment of this application, includes the following steps.

[0165] 701. The service access network device sends a node addition request to the target network device. The node addition request includes a connection indication.

[0166] The service access network device may send the node addition request to the target network device to request that the target network device establish a multi-connection operation in order to allocate a radio resource to the terminal device. Additionally, the message includes, but is not limited to, the following information: Identification information for a network slice that is serving the terminal device; Identification information for a network slice that the terminal device is permitted to access; Service area identification information for the network slice serving the terminal device; Service area identification information for a network slice required by the terminal device; A network slice service area priority, used to indicate a priority that corresponds to a network slice service area identifier, for example, a priority of network slice service area A is higher than that of network slice service area B; Configuration information for a network slice that corresponds to a network slice identifier, for example, a Physical Random Access Control (PRACH) physical channel configuration, a random access preamble configuration, a related configuration. Petition 870250050916, dated 06 / 17 / 2025, pp. 62 / 112 41 / 59 to security or a radio resource management-related configuration, which is not limited in this document; a terminal device security capability, used to indicate an encryption algorithm and an integrity protection algorithm that are supported by the terminal device; A security key of the target network device, used by the target network device to perform data encryption for the endpoint device. a maximum aggregate bit rate of the terminal device applicable to the target network device, which includes a maximum aggregate uplink bit rate and a maximum aggregate downlink bit rate; A server PLMN, used to indicate a PLMN that corresponds to a radio carrier that needs to be established by the target network device; Information about a carrier that needs to be established and that corresponds to one or more or all of the network slices selected by the terminal device, session information and / or flow information, for example, a carrier type, such as a master cell group bearer, a secondary cell group bearer, or a split bearer, a carrier identifier, quality of service information corresponding to a carrier, a tunnel endpoint, a session identifier, a flow identifier, quality of service information corresponding to a session, quality of service information corresponding to a flow, carrier-level, session-level or flow-level security information, for example, an encryption function enablement option,wherein a location of an encryption function is on the service access network device and / or on a network core, a header compression function enablement option, wherein a location of a header compression function is on the service access network device and / or on a network core, or an integrity protection enablement option, wherein an integrity protection location is on the service access network device and / or on a network core; or, Petition 870250050916, dated 06 / 17 / 2025, pp. 63 / 112 42 / 59 a list of handover restrictions, which includes a server PLMN, an equivalent PLMN, a list of prohibited or permitted tracking areas, a list of prohibited or permitted cells, or similar items not limited in this document.

[0167] 702. The target network device responds with a service access network device addition request confirmation to the service access network device, to indicate that the target network device has prepared resources.

[0168] Additionally, the message includes, but is not limited to, the following information: a list of a carrier, session, and / or flow that is not allowed, and the carrier, session, and / or flow correspond(s) to one or more or all of the network slices selected by the terminal device; information on a carrier, session, and / or flow that is allowed, and the carrier, session, and / or flow that correspond(s) to one or more or all of the network slices selected by the terminal device, for example, a carrier identifier, a session identifier, a flow identifier, a carrier-level QoS (quality of service) parameter, or a tunnel endpoint; or a transparent container from a target node to a source node, which includes carrier configuration information generated by the target network device.

[0169] Additionally, if the target network device cannot support any received network slice, radio carrier, session, stream, or similar, or an error occurs during a process, the target network device responds with a rejection message that carries a cause, for example, the network slice, radio carrier, session, stream, or similar cannot be supported.

[0170] 703. The service access network device sends a connection reconfiguration message to the terminal device. The connection reconfiguration message includes a target network slice service area identifier. The connection reconfiguration message is used to instruct the terminal device to connect to the target network device.

[0171] In some feasible embodiments, the service access network device may initiate an RRC connection reconfiguration message with the terminal device. The connection reconfiguration message Petition 870250050916, dated 06 / 17 / 2025, pp. 64 / 112 43 / 59 of RRC carries radio resource configuration information, used to instruct the terminal device to perform radio resource configuration based on the received message. Additionally, the message includes, but is not limited to, the following information: a network slice service area identifier supported by the target network device; a target cell identifier; a new temporary identifier of the terminal device; or a carrier configuration, for example, settings on a PDCP, RLC, MAC, and a physical layer.

[0172] 704. The terminal device responds to the service access network device with RRC connection reconfiguration completion, to indicate that the terminal device has completed the radio resource configuration.

[0173] 705. The service access network device sends service access network device configuration completion to the target network device, to indicate that the terminal device has completed the radio resource configuration.

[0174] IV. A service access network device sends a service access network device modification request to a target network device.

[0175] 801. The service access network device sends a node modification request to the target network device, wherein the node modification request is used to instruct the target network device to modify a radio resource configuration of the target network device to a terminal device.

[0176] In some feasible embodiments, two network devices may exchange a service area identifier of a network slice that is serving the terminal device or that is required by the terminal device, and a primary service access network device conditions a secondary service access network device to modify a current multi-connection operation. Specifically, the service access network device initiates the service access network device modification request with the target network device, to request the target network device to modify current context information of the terminal device and radio resource allocation prepared by the target network device for the Petition 870250050916, dated 06 / 17 / 2025, pp. 65 / 112 44 / 59 terminal device. Additionally, the message includes, but is not limited to, the following information: Identification information for a network slice serving the terminal device; identification information for a network slice that the terminal device is permitted to access; Service area identification information for the network slice serving the terminal device; Service area identification information for a network slice required by the terminal device; A network slice service area priority, used to indicate a priority that corresponds to a network slice service area identifier, for example, a priority of network slice service area A is higher than that of network slice service area B; An indication of a secondary cell group carrier modification, used to indicate whether a secondary cell group carrier needs to be modified; A security capability of the terminal device, used to indicate an encryption algorithm and an integrity protection algorithm that are supported by the terminal device; A security key for the target network device, used by the target network device to perform data encryption on the terminal device. a maximum aggregate bit rate of the terminal device applicable to the target network device, which includes a maximum aggregate uplink bit rate and a maximum aggregate downlink bit rate; Information about a carrier that needs to be established, modified, or released and that corresponds to one or more or all of the network slices selected by the terminal device; session information and / or flow information, for example, a carrier type, such as a master cell group bearer, a secondary cell group bearer, a split bearer; a carrier identifier; quality of service information corresponding to a carrier; a tunnel endpoint; a session identifier; a flow identifier; quality information. Petition 870250050916, dated 06 / 17 / 2025, pp. 66 / 112 45 / 59 service information corresponding to a session, quality of service information corresponding to a flow, security information at the carrier level, session level, or flow level, for example, an encryption function enablement option, wherein an encryption function location is on the service access network device and / or on a network core, a header compression function enablement option, wherein a header compression function location is on the service access network device and / or on a network core, or an integrity protection enablement option, wherein an integrity protection location is on the service access network device and / or on a network core; or a handover restriction list, which includes a server PLMN, an equivalent PLMN, a list of prohibited or permitted tracking areas, a list of prohibited or permitted cells, or similar.This is not limited to this document.

[0177] 802. The target network device responds to the service access network device with confirmation of the service access network device modification request, to confirm the modification request from the target network device.

[0178] Additionally, the message includes, but is not limited to, the following information: a list of a carrier, session, and / or flow that is not allowed, and the carrier, session, and / or flow corresponds to one or more or all of the network slices selected by the terminal device; information on a carrier, session, and / or flow that is allowed, and the carrier, session, and / or flow corresponds to one or more or all of the network slices selected by the terminal device, for example, allowed carrier information, allowed session information, and / or allowed flow information that needs to be added, modified, or released, a carrier identifier, a session identifier, a flow identifier, a carrier-level QoS (quality of service) parameter, or a tunnel endpoint;or a transparent container from a target node to a source node, which includes carrier configuration information generated by the target network device. Additionally, if the target network device cannot support any network slice, radio carrier, session, or flow; Petition 870250050916, dated 06 / 17 / 2025, page 67 / 112 If error 46 / 59 or similar is received, or an error occurs in a process, the target network device responds with a rejection message that carries a cause, for example, the network slice, radio carrier, session, flow, or similar cannot be supported. This is not limited to what is covered in this document.

[0179] 803. The service access network device sends a connection reconfiguration message to the terminal device, wherein the connection reconfiguration message includes the radio resource configuration.

[0180] Additionally, the message includes, but is not limited to, the following information: a network slice service area identifier supported by the target network device; a target cell identifier; a new temporary identifier of the terminal device; or a carrier configuration, for example, settings on a PDCP, RLC, MAC, and a physical layer.

[0181] 804. The terminal device responds to the service access network device with connection reconfiguration completion, to indicate that the terminal device has completed the radio resource configuration.

[0182] 805. The service access network device sends service access network device configuration completion to the target network device, to indicate that the terminal device has completed the radio resource configuration.

[0183] V. A service access network device receives a node modification request message sent by a target network device.

[0184] 901. The service access network device receives a node modification request sent by the target network device.

[0185] In some feasible embodiments, two network devices may exchange a service area identifier of a network slice that is serving a terminal device or that is required by a terminal device, and a secondary service access network device initiates modification of an existing multi-connection operation. Specifically, the service access network device may initiate the node modification request with the target network device, to condition the release of a radio resource, modify a primary server cell, reverse a sequence number of Petition 870250050916, dated 06 / 17 / 2025, pp. 68 / 112 47 / 59 Packet Data Convergence Protocol (PDCP), or similar.

[0186] Additionally, the message includes, but is not limited to, the following information: Identification information for a network slice that is serving the terminal device; Identification information for a network slice that the terminal device is permitted to access; Service area identification information for the network slice serving the terminal device; Service area identification information for a network slice required by the terminal device; A network slice service area priority, used to indicate a priority that corresponds to a network slice service area identifier, for example, a priority of network slice service area A is higher than that of network slice service area B; An indication of a secondary cell group carrier modification, used to indicate whether a secondary cell group carrier needs to be modified; Information about a carrier that needs to be released and that corresponds to one or more or all of the network slices selected by the terminal device, session information and / or flow information, for example, a carrier type, such as a master cell group bearer, a secondary cell group bearer, a split bearer, a carrier identifier, quality of service information corresponding to a carrier, a tunnel endpoint, a session identifier, a flow identifier, quality of service information corresponding to a session, quality of service information corresponding to a flow, security information at the carrier level, session level or flow level, for example, an encryption function enablement option,where a location of an encryption function is on the service access network device and / or on a network core, a header compression function enablement option, in, Petition 870250050916, dated 06 / 17 / 2025, pp. 69 / 112 48 / 59 where a header compression function location is on the service access network device and / or on a network core, or an integrity protection enablement option, where an integrity protection location is on the service access network device and / or on a network core; or a handover restriction list, which includes a server PLMN, an equivalent PLMN, a list of prohibited or permitted tracking areas, a list of prohibited or permitted cells, or similar.

[0187] 902. The service access network device initiates a service access network device modification request to the target network device. Optionally, when a data forwarding address, a security key from a secondary RAN device, or similar needs to be provided, the service access network device initiates a RAN device modification request with the target network device to request that the target network device modify the current context information of the terminal device and the radio resource allocation prepared by the target network device for the terminal device. Additionally, the message includes, but is not limited to: Identification information for a network slice that is serving the terminal device; Identification information for a network slice that the terminal device is permitted to access; Service area identification information for the network slice serving the terminal device; Service area identification information for a network slice required by the terminal device; A network slice service area priority is used to indicate a priority that corresponds to a network slice service area identifier, for example, a priority of network slice service area A is higher than that of network slice service area B; An indication of a secondary cell group carrier modification, used to indicate whether a secondary cell group carrier needs to be modified; Petition 870250050916, dated 06 / 17 / 2025, pp. 70 / 112 49 / 59 a terminal device security capability, used to indicate an encryption algorithm and an integrity protection algorithm that are supported by the terminal device; A security key for the target network device, used by the target network device to perform data encryption on the terminal device. a maximum aggregate bit rate of the terminal device applicable to the target network device, which includes a maximum aggregate uplink bit rate and a maximum aggregate downlink bit rate; Information about a carrier that needs to be established, modified, or released and that corresponds to one or more or all of the network slices selected by the terminal device; session information and / or flow information, for example, a carrier type, such as a master cell group bearer, a secondary cell group bearer, a split bearer; a carrier identifier; quality of service information corresponding to a carrier; a tunnel endpoint; a session identifier; a flow identifier; quality of service information corresponding to a session; quality of service information corresponding to a flow; security information at a carrier level, session level, or flow level, for example, an encryption function enablement option.where a cipher location is on a RAN device and / or a CN device, a header compression function enablement option, where a header compression function location is on a RAN device and / or a CN device, or an integrity protection enablement option, where an integrity protection location is on a RAN device and / or a CN device; or a handover restriction list, which includes a server PLMN, an equivalent PLMN, a list of prohibited or permitted tracking areas, a list of prohibited or permitted cells, or similar.

[0188] 903. The target network device responds to the service access network device with confirmation of the node modification request, to indicate that the target network device has prepared resources. Petition 870250050916, dated 06 / 17 / 2025, pp. 71 / 112 50 / 59

[0189] Additionally, the message includes, but is not limited to, the following information: a list of a carrier, session, and / or flow that is not allowed, and the carrier, session, and / or flow correspond(s) to one or more or all of the network slices selected by the terminal device; information of a carrier, session, and / or flow that is allowed, and the carrier, session, and / or flow corresponds to one or more or all of the network slices selected by the terminal device, for example, allowed carrier information, allowed session information, and / or allowed flow information that needs(s) to be added, modified, or released, a carrier identifier, a session identifier, a flow identifier, a carrier-level QoS (quality of service) parameter, or a tunnel endpoint;or a transparent container from a target node to a source node, which includes carrier configuration information generated by the target network device.

[0190] Additionally, if the target network device cannot support any received network slice, radio carrier, session, stream, or similar, or an error occurs in a process, the target network device responds with a rejection message that carries a cause, for example, the network slice, radio carrier, session, stream, or similar cannot be supported.

[0191] 904. The target network device responds to the service access network device with service access network device modification request confirmation, to confirm the modification request from the target network device.

[0192] Additionally, the message includes, but is not limited to, the following information: a list of a carrier, session, and / or flow that is not allowed, and the carrier, session, and / or flow correspond(s) to one or more or all of the network slices selected by the terminal device; information on a carrier, session, and / or flow that is allowed, and the carrier, session, and / or flow correspond(s) to one or more or all of the network slices selected by the terminal device, for example, allowed carrier information, allowed session information, and / or allowed flow information that needs(s) to be added, modified, or released, a carrier identifier, an identifier of Petition 870250050916, dated 06 / 17 / 2025, pp. 72-112 51 / 59 session, a flow identifier, a carrier-level QoS (quality of service) parameter, or a tunnel endpoint; or a transparent container from a target node to a source node, which includes carrier configuration information generated by the target network device.

[0193] Additionally, if the target network device cannot support any received network slice, radio carrier, session, stream, or similar, or an error occurs in a process, the target network device responds with a rejection message that carries a cause, for example, the network slice, radio carrier, session, stream, or similar cannot be supported.

[0194] 905. The service access network device initiates an RRC connection reconfiguration message with a terminal device, wherein the RRC connection reconfiguration message carries radio resource configuration information, to instruct the terminal device to perform radio resource configuration based on the received message.

[0195] Additionally, the message includes, but is not limited to, the following information: a network slice service area identifier supported by the target network device; a target cell identifier; a new temporary identifier of the terminal device; or a carrier configuration, for example, settings on a PDCP, RLC, MAC, and a physical layer. This is not limited in this document.

[0196] 906. The terminal device responds to the service access network device with RRC connection reconfiguration completion, to indicate that the terminal device has completed the radio resource configuration.

[0197] 907. The service access network device sends service access network device configuration completion to the target network device, to indicate that the terminal device completes the radio resource configuration.

[0198] The preceding section describes the method of accessing the target cell, and the following section describes a related device. Referring to Figure 10, Figure 10 shows a terminal device 1000, which includes: a first acquisition module 1001, configured to obtain a network slice service area identifier from a device of Petition 870250050916, dated 06 / 17 / 2025, pp. 73 / 112 52 / 59 service access network that corresponds to a server cell in which the terminal device is located, where the network slice service area identifier is used to indicate an area served by a network slice; a determination module 1002, configured to determine a target cell based on network slice configuration information and the network slice service area identifier, wherein the network slice configuration information includes a match between a network slice, an area, and a service; and an access module 1003, configured to access the target cell.

[0199] Referring to Figure 11, terminal device 1000 additionally includes: a second 1004 acquisition module, configured to obtain network slice configuration information from a network core.

[0200] Referring to Figure 12, the second acquisition module 1004 includes: A first transmitter submodule 10041, configured to send a request message to the network core, where the request message is used to request network slice configuration information; and a receiver submodule 10042, configured to receive network slice configuration information from the network core.

[0201] Referring to Figure 13, the first acquisition module 1001 includes: a second transmitter submodule 10011, configured to send an indication message to the service access network device, where the indication message is used to indicate a requirement for a network slice; and a fetch submodule 10012, configured to obtain the network slice service area identifier from the service access network device.

[0202] Referring to Figure 14, Figure 14 shows a 1400 service access network device, which includes: A first transmitter module, 1401, is configured to send a connection indication to a target network device. The connection indication is... Petition 870250050916, dated 06 / 17 / 2025, pp. 74 / 112 53 / 59 used to instruct the target network device to connect to a terminal device; and a second transmitter module 1402, configured to send a target network slice service area identifier to the terminal device, wherein the target network slice service area identifier is used to indicate a target area, so that the terminal device determines a target cell based on network slice configuration information and the network slice service area identifier, wherein the network slice configuration information includes a match between a network slice, an area, and a service.

[0203] Referring to Figure 15, the first transmitter module 1401 includes: A first transmitter submodule, 14011, is configured to send a handover request to the target network device. The handover request includes a connection indication.

[0204] The second transmitter module 1402 includes: a second transmitter submodule 14021, configured to send a handover command to the terminal device, wherein the handover command includes the target network slice service area identifier, and the handover command instructs the terminal device to transfer via handover to the target network device.

[0205] Referring to Figure 16, the first transmitter module 1401 includes: a third transmitter submodule 14012, configured to send a node addition request to the target network device, where the node addition request includes the connection indication.

[0206] The second transmitter module 1402 includes: a fourth transmitter submodule 14022, configured to send a connection reconfiguration message to the terminal device, wherein the connection reconfiguration message includes the target network slice service area identifier, and the connection reconfiguration message is used to instruct the terminal device to connect to the target network device.

[0207] Referring to Figure 17, the network access device Petition 870250050916, dated 06 / 17 / 2025, pp. 75 / 112 54 / 59 service 1400 additionally includes: a third transmitter module 1403, configured to send a node modification request to the target network device, wherein the node modification request is used to instruct the target network device to modify a radio resource configuration from the target network device to the terminal device; and a first receiver module 1404, configured to send a connection reconfiguration message to the terminal device, wherein the connection reconfiguration message includes the radio resource configuration.

[0208] Referring to Figure 18, the 1400 service access network device additionally includes: a second 1405 receiver module, configured to receive a node modification request sent by the target network device.

[0209] The preceding section describes the embodiments of this application from the perspective of a modular function entity, and the following section describes the embodiments of this application from a hardware processing perspective. Referring to Figure 19, one embodiment of this application provides a 1900 terminal device, which includes: a transceiver 1901, a memory 1902, a processor 1903 and a bus 1904.

[0210] Transceiver 1901, memory 1902 and processor 1903 are connected using bus 1904.

[0211] Transceiver 1901 is configured to obtain a network slice service area identifier from a service access network device that corresponds to a server cell in which the terminal device is located, where the network slice service area identifier is used to indicate an area served by a network slice.

[0212] The 1901 transceiver may include a communications interface (English: communication interface) between the 1903 processor and a standard communications subsystem.

[0213] The 1901 transceiver may additionally include a communications interface in an EIA-RS-232C standard, namely, a communications interface in a data exchange interface technology standard. Petition 870250050916, dated 06 / 17 / 2025, pp. 76 / 112 55 / 59 binary serial communication between Data Terminal Equipment (DTE) and Data Circuit-terminating Equipment (DCE), or it may include a communications interface using an RS-485 protocol. This is not limited to what is covered in this document.

[0214] Processor 1903 is configured to: determine a target cell based on network slice configuration information and the network slice service area identifier, wherein the network slice configuration information includes a match between a network slice, an area, and a service; and access the target cell.

[0215] The 1903 processor can be a central processing unit (CPU), a network processor (NP), or a combination of a CPU and an NP.

[0216] The 1903 processor may additionally include a hardware chip. The hardware chip may be an application-specific integrated circuit (ASIC), a programmable logic device (PLD), or a combination thereof. The PLD may be a complex programmable logic device (CPLD), a field-programmable gate array (FPGA), generic array logic (GAL), or any combination thereof.

[0217] Memory 1902 is configured to store a program, a target area, a target service, and network slice configuration information.

[0218] 1902 memory may include volatile memory, for example, random-access memory (RAM). 402 memory may also include non-volatile memory, for example, flash memory, a hard disk drive (HDD), or a solid-state drive (SSD). 403 memory may additionally include a combination of the preceding memories. This is not limited to the present document.

[0219] Optionally, memory 1902 can be further configured to store a program instruction. Processor 403 can invoke the program instruction stored in memory 1902 to perform the optional step or deployment in the mode shown in Figure 2. Petition 870250050916, dated 06 / 17 / 2025, pp. 77 / 112 56 / 59 so that the terminal device 1900 implants the function in the preceding method.

[0220] Referring to Figure 20, Figure 20 shows a 2000 service access network device, which includes: a transceiver 2001, a memory 2002, a processor 2003 and a bus 2004.

[0221] Transceiver 2001, memory 2002 and the processor are connected using the bus.

[0222] Transceiver 2001 is configured to: send a connection indication to a target network device, wherein the connection indication is used to instruct the target network device to connect to a terminal device; and send a target network slice service area identifier to the terminal device, wherein the target network slice service area identifier is used to indicate a target area, such that the terminal device determines a target cell based on network slice configuration information and the network slice service area identifier, wherein the network slice configuration information includes a match between a network slice, an area, and a service.

[0223] The 2001 transceiver may include a communication interface between the 2003 processor and a standard communication subsystem.

[0224] The 2001 transceiver may additionally include a communications interface in an EIA-RS-232C standard, namely, a communications interface in a serial binary data exchange interface technology standard between Data Terminal Equipment (DTE) and Data Circuit-terminating Equipment (DCE), or it may include a communications interface in an RS-485 protocol. This is not limited to the scope of this document.

[0225] Memory 2002 is configured to store a program, a target area, a target service, and network slice configuration information.

[0226] Memory 2002 may include volatile memory, for example, random-access memory (RAM). Memory 402 may also include non-volatile memory. Petition 870250050916, dated 06 / 17 / 2025, pp. 78 / 112 57 / 59 (non-volatile memory), for example, flash memory, a hard disk drive (HDD), or a solid-state drive (SSD). 403 memory may also include a combination of the preceding memories. This is not limited to the scope of this document.

[0227] Optionally, memory 2002 can be further configured to store a program instruction. Processor 403 can invoke the program instruction stored in memory 2002 to perform the step or optional deployment in the mode shown in Figure 2, so that the service access network device 2000 deploys the function in the preceding method.

[0228] The 2003 processor is configured to perform a service access network device function.

[0229] The 2003 processor can be a central processing unit (CPU), a network processor (NP), or a combination of a CPU and an NP.

[0230] The 2003 processor may additionally include a hardware chip. The hardware chip may be an application-specific integrated circuit (ASIC), a programmable logic device (PLD), or a combination thereof. The PLD may be a complex programmable logic device (CPLD), a field-programmable gate array (FPGA), generic array logic (GAL), or any combination thereof.

[0231] It may be clearly understood by persons skilled in the art that, for the purpose of convenient and brief description, for a detailed operating process of the preceding system, apparatus and unit, reference may be made to a corresponding process in the modalities of the preceding method, and the details are not described in this document.

[0232] In the various embodiments provided in this application, it should be understood that the system, apparatus and method disclosed may be implemented in other ways. For example, the apparatus embodiment described is only one example. For example, the unit division is merely a logical function division and may be another division in the actual implementation. For example, a Petition 870250050916, dated 06 / 17 / 2025, pp. 79 / 112 58 / 59 A plurality of units or components can be combined or integrated into another system, or some features may be ignored or not implemented. Furthermore, the mutual couplings or direct couplings or communication connections shown or discussed can be implemented using certain interfaces. Indirect couplings or communication connections between devices or units can be implemented electronically, mechanically, or in other ways.

[0233] The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one position, or may be distributed across a plurality of network units. Some or all of the units may be selected according to actual needs to achieve the objectives of the modal solutions.

[0234] All or some of the preceding embodiments may be implemented using software, hardware, firmware, or any combination thereof. When software is used to implement the embodiments, the embodiments may be implemented, in whole or in part, in the form of a computer program product.

[0235] The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on the computer, the procedures or functions, according to the embodiments of the present invention, are generated wholly or partially. The computer may be a general-purpose computer, a dedicated computer, a computer network, or other programmable device. The computer instructions may be stored on a computer-readable storage medium, or may be transmitted from one computer-readable storage medium to another computer-readable storage medium.For example, computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center in a wired manner (e.g., a coaxial cable, fiber optic cable, or digital subscriber line (DSL)) or wirelessly (e.g., infrared, radio, or microwave). Computer-readable storage media can be any usable media accessible by a computer, or... Petition 870250050916, dated 06 / 17 / 2025, pages 80 / 112 59 / 59 a data storage device, such as a server or data center, that integrates one or more usable media. The usable media may be magnetic media (e.g., a floppy disk, a hard disk, or magnetic tape), optical media (e.g., a DVD), semiconductor media (e.g., a solid-state disk (SSD)), or similar.

[0236] In conclusion, the preceding embodiments are intended only to describe the technical solutions of this application and not to limit this application. Although this application is described in detail with reference to the preceding embodiments, persons of ordinary skill in the art should understand that they may still make modifications to the technical solutions described in the preceding embodiments or make equivalent substitutions in some technical features thereof, without departing from the scope of the technical solutions of the embodiments of this application. Petition 870250050916, dated 06 / 17 / 2025, pp. 81 / 112

Claims

1 / 8 CLAIMS 1. A method for communications, CHARACTERIZED in that it comprises: sending, by a service access network device, a node addition request message (701) to a target network device, wherein the node addition request message comprises identification information of a network slice serving a terminal device, the node addition request message further comprises an encryption function enablement option indicating whether an encryption function is enabled for a session and an integrity protection enablement option indicating whether integrity protection is enabled for the session; receiving, by the service access network device, a node addition request confirmation message (702) from the target network device.

2. Method according to claim 1, CHARACTERIZED in that the network slice identification information comprises a type of network slice.

3. A method according to claim 1 or 2, characterized in that the method further comprises: sending, by the service access network device, an RRC connection reconfiguration message to the terminal device, wherein the RRC connection reconfiguration message comprises radio resource configuration information; receiving, by the service access network device, an RRC connection reconfiguration completion message from the terminal device; and sending, by the service access network device, a message used to indicate that the terminal device has completed radio resource configuration to the target network device.

4. A method, according to any one of claims 1 to 3, CHARACTERIZED in that the node addition request message additionally includes session-level security information.

5. Method, according to any one of claims 1 to 4, CHARACTERIZED in that the confirmation message of the add-on request Petition 870250074494, dated 08 / 22 / 2025, page 16 / 23 2 / 8 additionally comprises: a list of sessions that are admitted and that correspond to a network slice selected by the terminal device.

6. A method, according to any one of claims 1 to 5, CHARACTERIZED in that the add-on request confirmation message additionally comprises: a non-admitted stream list.

7. A method, according to any one of claims 1 to 6, CHARACTERIZED in that the node addition request message additionally comprises carrier information that needs to be established and that corresponds to one or more or all of the network slices selected by the terminal device.

8. A method according to any one of claims 1 to 7, characterized in that the node addition request message additionally comprises a carrier type, the carrier type comprising a secondary cell group carrier and a split carrier.

9. A method, according to any one of claims 1 to 8, characterized in that the node addition request message additionally includes quality of service information corresponding to a session.

10. A method, according to any one of claims 1 to 9, CHARACTERIZED in that the node addition request message additionally comprises a flow identifier and quality of service information corresponding to the flow.

11. A method, according to any one of claims 1 to 10, CHARACTERIZED in that the RRC connection reconfiguration message additionally comprises a target cell identifier.

12. Method for communications, CHARACTERIZED by the fact that it comprises: receiving, by a target network device, a node addition request message from a service access network device, wherein the node addition request message comprises identification information of a network slice that is serving a terminal device, the node addition request message further comprises an encryption function enablement option indicating whether an encryption function is enabled for a session and an integrity protection enablement option indicating whether integrity protection is enabled for the session; and sending, by the target network device, a node addition request confirmation message to the service access network device.

13. Access network device, CHARACTERIZED in that it comprises: a module configured to send a node addition request message to a target network device, wherein the node addition request message comprises identification information of a network slice that is serving a terminal device, the node addition request message further comprises an encryption function enablement option indicating whether an encryption function is enabled for a session and an integrity protection enablement option indicating whether integrity protection is enabled for the session; and a module configured to receive an addition request confirmation message from the target network device.

14. Network device, CHARACTERIZED in that it comprises: a module configured to receive a node addition request message from a service access network device, wherein the node addition request message comprises identification information of a network slice serving a terminal device, the node addition request message further comprises an encryption function enablement option indicating whether an encryption function is enabled for a session and an integrity protection enablement option indicating whether integrity protection is enabled for the session; and a module configured to send an addition request confirmation message to the service access network device.

15. Method for communications, CHARACTERIZED by the fact that it comprises: sending, through a service access network device, a node addition request message to a target network device, in which Petition 870250074494, dated 08 / 22 / 2025, page.18 / 23 4 / 8 The node addition request message comprises a connection indication and identification information of a network slice serving a terminal device; the node addition request message further comprises an encryption function enablement option indicating whether an encryption function is enabled for a session and an integrity protection enablement option indicating whether integrity protection is enabled for the session; the target network device receives the node addition request message; the target network device sends a node addition request confirmation message to the service access network device; and the service access network device receives the node addition request confirmation message.

16. System for communications, CHARACTERIZED in that it comprises: a service access network device and a target network device; the service access network device is configured to send a node addition request message to the target network device, wherein the node addition request message comprises identification information of a network slice that is serving a terminal device, the node addition request message further comprises an encryption function enablement option indicating whether an encryption function is enabled for a session and an integrity protection enablement option indicating whether integrity protection is enabled for the session; the target access network device is configured to send a node addition request confirmation message to the service network device.

17. Method for communications, CHARACTERIZED by the fact that it comprises: sending a handover request to a target network device, wherein the handover request comprises session information that needs to be established and that corresponds to a network slice selected by a terminal device, and the session information comprises a session identifier and security-level information. Petition 870250074494, dated 08 / 22 / 2025, p.19 / 23 5 / 8 session, and wherein the session-level security information comprises an encryption function enable option that indicates whether an encryption function is enabled for a session and an integrity protection enable option that indicates whether integrity protection is enabled for the session; receive handover request confirmation from the target network device; and send a Radio Resource Control (RRC) message to the terminal device, wherein the RRC message carries a handover command.

18. Method according to claim 17, CHARACTERIZED in that the flow information comprises a flow identifier and a service parameter flow level quality.

19. A method, according to any one of claims 17 to 18, CHARACTERIZED in that the handover request confirmation further comprises: a list of a session that is not admitted, the session corresponding to the network slice selected by the terminal device; or a list of a flow that is not admitted, and the flow corresponding to the network slice selected by the terminal device.

20. Method for communications, CHARACTERIZED in that it comprises: receiving a handover request from a service access network device, wherein the handover request comprises session information that needs to be established and that corresponds to a network slice selected by a terminal device, and the session information comprises a session identifier and session-level security information, and wherein the session-level security information comprises an encryption function enablement option indicating whether an encryption function is enabled for a session and an integrity protection enablement option indicating whether integrity protection is enabled for the session; and sending handover request confirmation to the service access network device. Petition 870250074494, dated 08 / 22 / 2025, p. 20 / 23 6 / 8 21. Communications device, CHARACTERIZED in that it comprises: a module configured to send a handover request to a target network device, wherein the handover request comprises session information that needs to be established and that corresponds to a network slice selected by a terminal device, and the session information comprises a session identifier and session-level security information, and wherein the session-level security information comprises an encryption function enable option indicating whether an encryption function is enabled for a session and an integrity protection enable option indicating whether integrity protection is enabled for the session; a module configured to receive handover request confirmation from the target network device;and a module configured to send a Radio Resource Control (RRC) message to the terminal device, where the RRC message carries a handover command.

22. Communications apparatus, CHARACTERIZED in that it comprises: a module configured to receive a handover request from a service access network device, wherein the handover request comprises session information that needs to be established and that corresponds to a network slice selected by a terminal device, and the session information comprises a session identifier, a session-level quality of service parameter, a tunnel endpoint, and session-level security information, and wherein the session-level security information comprises an encryption function enablement option indicating whether an encryption function is enabled for a session and an integrity protection enablement option indicating whether integrity protection is enabled for the session;and a module configured to send handover request confirmation to the service access network device.

23. Communication apparatus, CHARACTERIZED in that it comprises a transceiver, a processor, and a memory that are connected using a bus, wherein the memory is configured to store an instruction, the processor is configured to execute the instruction stored in memory, to control the transceiver to receive and send a signal, and when the processor executes the instruction stored in memory, the communication apparatus is configured to complete the method as defined in any one of claims 1 to 12, or 15, or 17 to 20.

24. Computer-readable storage media, configured to store an instruction, CHARACTERIZED in that when the instruction runs on a processor, the method as defined in any one of claims 1 to 12, or 15, or 17 to 20.

25. Method for communications, CHARACTERIZED in that it comprises: sending, by a service access network device, a handover request to a target network device, wherein the handover request comprises session information that needs to be established and that corresponds to a network slice selected by an end device, and the session information comprises a session identifier, a session-level quality of service parameter, a tunnel endpoint, and session-level security information, and wherein the session-level security information comprises an encryption function enablement option indicating whether an encryption function is enabled for a session and an integrity protection enablement option indicating whether integrity protection is enabled for the session; receiving, by the target network device, the handover request;The target network device sends a handover request confirmation to the service access network device; the service access network device receives the handover request confirmation; and the service access network device sends a Radio Resource Control (RRC) message to the terminal device, where the RRC message carries a handover command.

26. Communications system, CHARACTERIZED by the fact that it comprises: a service access network device and a device. Petition 870250074494, dated 08 / 22 / 2025, page.22 / 23 8 / 8 target network; the service access network device is configured to send a handover request to the target network device, wherein the handover request comprises session information that needs to be established and that corresponds to a network slice selected by an endpoint device, and the session information comprises a session identifier, a session-level quality of service parameter, a tunnel endpoint, and session-level security information, and wherein the session-level security information comprises an encryption function enable option that indicates whether an encryption function is enabled for a session and an integrity protection enable option that indicates whether integrity protection is enabled for the session; the target network device is configured to send handover request confirmation to the service access network device.Petition 870250074494, dated 08 / 22 / 2025, p. 23 / 23.

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