CN115379531A

CN115379531A - Communication method and communication device

Info

Publication number: CN115379531A
Application number: CN202110547873.4A
Authority: CN
Inventors: 雷中定
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2021-05-19
Filing date: 2021-05-19
Publication date: 2022-11-22
Also published as: WO2022242452A1

Abstract

The application provides a communication method and a communication device, comprising the following steps: the method comprises the steps that terminal equipment sends a request for accessing a target network slice to first network equipment, wherein the request message comprises identification information of a network slice group to which the target network slice belongs and first identification information of the target network slice, and the first identification information of the target network slice is generated after single network slice selection auxiliary information S-NSSAI of the target network slice is modified; the method can increase the possibility that the first network equipment selects the second network equipment which can serve the target network slice requested to be accessed by the terminal equipment on the premise of avoiding revealing sensitive information of the network slice.

Description

Communication method and communication device

Technical Field

The present application relates to the field of communications, and more particularly, to a communication method and a communication apparatus in the field of communications.

Background

When the terminal equipment wants to access a certain network slice, the terminal equipment can report the network slice which the terminal equipment wants to access to the network equipment through an uplink message, and the network equipment helps the terminal equipment to establish connection with the network slice according to the request of the terminal equipment.

However, not all network slices can be reported to the network device by the terminal device through the uplink message, that is, in some cases, the terminal device cannot report the network slices to the network device through the uplink message, and at this time, the network device does not know which network slice the terminal device wants to access.

Disclosure of Invention

The application provides a communication method and a communication device, which can increase the possibility that a first network device selects a second network device which can serve a target network slice requested to be accessed by a terminal device on the premise of avoiding leakage of sensitive information of the network slice.

In a first aspect, a communication method is provided, including: a terminal device (which may also be a module in the terminal device, such as a chip) sends a first request message to a first network device, where the first request message requests to access a target network slice, and the first request message includes identification information of a network slice group to which the target network slice belongs and first identification information of the target network slice; the terminal device receives a response message from the first network device, wherein the response message indicates that the second network device allows the terminal device to access the target network slice.

In an implementation manner, when single network slice selection assistance information (S-NSSAI) of a target network slice may be sent in an access stratum, a first request message may carry first identification information of the target network slice, where the first identification information is an S-NSSAI of the target network slice; or, when the S-NSSAI of the target network slice may not be sent in the access stratum, the first request message may carry identification information of a network slice group to which the target network slice belongs.

Based on the technical scheme, when the S-NSSAI of the target network slice can be sent at an access layer, the terminal equipment sends the S-NSSAI of the target network slice to the first network equipment, and the first network equipment can select the second network equipment for the target network slice according to the S-NSSAI; when the S-NSSAI of the target network slice may not be sent in the access layer, the terminal device sends, to the first network device, identification information of a network slice group to which the target network slice belongs, and since the network slice group to which the target network slice belongs includes a plurality of network slices, it is unclear, by an eavesdropper, which network slice in the network slice group to which the target network slice belongs is a sensitive network slice, and therefore, even if the eavesdropper eavesdrops identification information of the network slice group to which the target network slice belongs, it is impossible to know whether the target network slice to which the terminal device intends to access belongs to the sensitive network slice, and in addition, by sending, to the first network device, identification information of the network slice group to which the target network slice belongs, the first network device can select a second network device for the target network slice according to the identification information of the network slice group to which the target network slice belongs and a correspondence between the identification information and the second network device, in this case, a possibility of selecting a second network device that can serve the target network slice to which the terminal device can request access can be increased.

In another implementation manner, when the S-NSSAI of the target network slice may be sent in the access stratum, the first request message may carry the S-NSSAI of the target network slice and identification information of a network slice group to which the target network slice belongs; or, when the S-NSSAI of the target network slice may not be sent at the access stratum, the first request message may carry identification information of the pseudonymized S-NSSAI (pS-NSSAI) of the target network slice and a network slice group to which the target network slice belongs, where the pS-NSSAI and the S-NSSAI have the same format but not the same or different content.

Based on the technical scheme, no matter whether the S-NSSAI of the target network slice can be sent in an access layer or not, the terminal device sends first identification information of the target network slice and identification information of a network slice group to which the target network slice belongs to the first network device, when the S-NSSAI of the target network slice can be sent in the access layer, the first identification information of the target network slice is S-NSSAI, and when the S-NSSAI of the target network slice cannot be sent in the access layer, the first identification information of the target network slice is pS-NSSAI, wherein the target network slice pS-NSSAI and the target network slice S-NSSAI are in the same format but not completely same or different in content.

Since the target network slice pS-NSSAI has the same format as the target network slice S-NSSAI, but the content is not completely the same or completely different, even if the eavesdropper overhears the first identification information, the eavesdropper cannot determine whether the first identification information is the S-NSSAI of the non-sensitive network slice or the pS-NSSAI corresponding to the S-NSSAI of the sensitive network slice, and therefore, the eavesdropper cannot know whether the target network slice to which the terminal device wants to access belongs to the sensitive network slice according to the first identification information.

In addition, by sending the identification information of the network slice group to which the target network slice belongs to the first network device, the first network device may select the second network device for the target network slice according to the identification information of the network slice group to which the target network slice belongs and the correspondence between the identification information and the second network device. It should be noted that, in the present application, the first identification information is identifiable about S-NSSAI of the non-sensitive network slice or pS-NSSAI corresponding to S-NSSAI of the sensitive network slice.

In another implementation, when the S-NSSAI of the target network slice may be sent at the access stratum, the first request message may carry a customized S-NSSAI (cS-NSSAI) of the target network slice, where the cS-NSSAI carries identification information of a network slice group to which the target network slice belongs, and information carried by the rest bits of the cS-NSSAI except for the identification information of the network slice group to which the target network slice belongs is a real S-NSSAI of the target network slice; or, when the S-NSSAI of the target network slice may not be sent in the access stratum, the first request message may carry a cS-NSSAI of the target network slice, where the cS-NSSAI carries identification information of a network slice group to which the target network slice belongs, and information carried by the remaining bits of the cS-NSSAI except the identification information of the network slice group to which the target network slice belongs is not the real S-NSSAI of the target network slice.

Based on the technical scheme, no matter whether the S-NSSAI of the target network slice can be sent at the access stratum or not, the terminal device sends the cS-NSSAI to the first network device, at this time, the first identification information is the cS-NSSAI, when the S-NSSAI of the target network slice can be sent at the access stratum, the cS-NSSAI carries the identification information of the network slice group to which the target network slice belongs, and the information carried by the rest bits except the identification information in the cS-NSSAI is the real S-NSSAI of the target network slice, when the S-NSSAI of the target network slice cannot be sent at the access stratum, the identification information carried by the rest bits except the identification information in the cS-NSSAI carries the identification information of the network slice group to which the target network slice belongs, and the information carried by the rest bits except the identification information of the cS-NSSAI is not the real S-NSSAI of the target network slice.

Whether the S-NSSAI of the target network slice can be sent at an access layer or not, the terminal device sends the cS-NSSAI to the first network device, so that even if an eavesdropper overhears the cS-NSSAI, the eavesdropper cannot determine whether the information carried by the rest bits except the identification information of the network slice group to which the target network slice belongs in the cS-NSSAI is the S-NSSAI of the non-sensitive network slice or the non-real S-NSSAI of the sensitive network slice, therefore, the eavesdropper cannot know whether the target network slice to which the terminal device wants to access belongs to the sensitive network slice according to the information carried by the rest bits except the identification information in the cS-NSSAI, and in addition, because the network slice group to which the target network slice belongs comprises a plurality of network slices, the eavesdropper cannot know which network slice in the network slice group to which the target network slice belongs to which the eavesdropper belongs to the sensitive network slice is the sensitive network slice, and even if the eavesdropper overhears the cS-NSSAI, the network slice group to which the terminal device wants to access to the sensitive network slice belongs to the sensitive network slice group to which the target network slice belongs to the eavesdropper does not know whether the sensitive network slice.

In addition, by sending the identification information of the network slice group to which the target network slice belongs to the first network device, the first network device may select the second network device for the target network slice according to the identification information of the network slice group to which the target network slice belongs and the correspondence between the identification information and the second network device. It should be noted that, in the present application, the first network device is identifiable with respect to the information carried by the remaining bits of the cS-NSSAI except the identification information, which is the S-NSSAI of the non-sensitive network slice or the non-real S-NSSAI of the sensitive network slice.

In summary, based on the above technical solution, for a target network slice that may cause sensitive information to be leaked if the S-NSSAI is sent in the access stratum, the method can increase the possibility that the first network device selects a correct second network device for the target network slice (i.e., a second network device that can serve the target network slice to which the terminal device requests to access) on the premise of avoiding leaking the sensitive information of the target network slice.

In addition, the method can also enable the first network device to execute congestion control for the terminal device which requests to access or has accessed the target network slice, thereby effectively reducing the problems of time delay increase and signaling resource consumption caused by the redirection flow, improving the user experience, and dynamically optimizing the network performance of the network slice.

With reference to the first aspect, in certain implementations of the first aspect, the identification information of the network slice group to which the target network slice belongs is carried in the first identification information of the target network slice.

With reference to the first aspect and the foregoing implementation manners, in some implementation manners of the first aspect, the identification information of the second network device is carried in the identification information of the network slice group to which the target network slice belongs.

Based on the above technical solution, by loading the identification information of the second network device in the identification information of the network slice group to which the target network slice belongs, the first network device may obtain the identification information of the second network device after receiving the identification information of the network slice group to which the target network slice belongs, so that the first network device may select the second network device for the target network slice according to the identification information of the second network device.

With reference to the first aspect and the foregoing implementation manners, in some implementation manners of the first aspect, the identification information of the second network device includes at least one of an identification of an area corresponding to the second network device, an identification of a network device set to which the second network device belongs, and a pointer corresponding to the second network device.

With reference to the first aspect and the foregoing implementation manners, in some implementation manners of the first aspect, the first identification information of the target network slice is generated by modifying single network slice selection assistance information S-NSSAI of the target network slice.

Based on the technical scheme, when the S-NSSAI of the target network slice cannot be sent in the access layer, the S-NSSAI of the target network slice is modified to generate the pS-NSSAI of the target network slice, and the first request message carries the pS-NSSAI of the target network slice and the identification information of the network slice group to which the target network slice belongs.

With reference to the first aspect and the foregoing implementation manners, in some implementation manners of the first aspect, the second network device is an access and mobility management function AMF.

In a second aspect, a communication method is provided, including: a first network device receives a first request message from a terminal device, wherein the first request message requests to access a target network slice, and the first request message comprises identification information of a network slice group to which the target network slice belongs and first identification information of the target network slice; in response to the first request message, the first network device sending a second request message to a second network device; the first network device receiving a response message from the second network device, the response message indicating that the second network device allows the terminal device to access the target network slice; and the first network equipment sends the response message to the terminal equipment.

For corresponding beneficial effects of the above technical solutions, please refer to the corresponding beneficial effects of the first aspect, and for brevity, details are not repeated here.

With reference to the second aspect, in some implementation manners of the second aspect, the first network device obtains association information, where the association information includes a correspondence between identification information of a network slice group to which the target network slice belongs and the second network device, and/or the association information includes a correspondence between the first identification information and the second network device; the sending, by the first network device to a second network device in response to the first request message, a second request message includes: and the first network equipment sends a second request message to the second network equipment according to at least one item of the identification information and the first identification information of the network slice group to which the target network slice belongs and the associated information.

Based on the above technical solution, the first network device obtains the association information, so as to obtain a correspondence between the identification information of the network slice group to which the target network slice belongs and the second network device, and a correspondence between the first identification information and the second network device, so that after receiving the first request message, the first network device can select the second network device for the target network slice according to at least one item of the first identification information and the identification information of the network slice group to which the target network slice belongs, and in combination with the association information, in this case, the possibility of selecting the second network device capable of serving the target network slice to which the terminal device requests access can be increased.

With reference to the second aspect and the foregoing implementation manners, in some implementation manners of the second aspect, the information about the identity of the second network device is carried in the identification information of the network slice group to which the target network slice belongs, and the sending, by the first network device, a second request message to the second network device in response to the first request message includes: and the first network equipment sends the second request message to the second network equipment according to the identification information of the second network equipment.

With regard to the corresponding advantageous effects of the above technical solutions, please refer to the corresponding advantageous effects of the first aspect, which is not described herein again for brevity.

With reference to the second aspect and the foregoing implementation manners, in some implementation manners of the second aspect, the identification information of the second network device includes at least one of an identification of an area corresponding to the second network device, an identification of a network device set to which the second network device belongs, and a pointer corresponding to the second network device.

With reference to the second aspect and the foregoing implementation manners, in some implementation manners of the second aspect, the identification information of the network slice group to which the target network slice belongs is carried in the first identification information.

With reference to the second aspect and the foregoing implementation manners, in some implementation manners of the second aspect, the first identification information of the target network slice is generated after S-NSSAI modification of the target network slice.

With reference to the second aspect and the foregoing implementation manners, in some implementation manners of the second aspect, the second network device is an AMF.

In a third aspect, a communication device is provided for performing the method of any one of the possible implementations of the above aspects. In particular, the apparatus comprises means for performing the method in any one of the possible implementations of the aspects described above.

In a fourth aspect, a communication device is provided, which includes a processor coupled to a memory and configured to execute instructions in the memory to implement the method in the first aspect or any one of the possible implementations of the first aspect, or the method in any one of the possible implementations of the second aspect or the second aspect.

In one possible implementation, the apparatus further includes a memory. In one possible implementation, the apparatus further includes a communication interface, the processor coupled with the communication interface.

In one implementation, the apparatus is a terminal device. When the apparatus is a terminal device, the communication interface may be a transceiver, or an input/output interface.

In another implementation, the apparatus is a chip configured in a terminal device. When the apparatus is a chip configured in a terminal device, the communication interface may be an input/output interface.

In one implementation, the apparatus is a first network device. When the apparatus is a first network device, the communication interface may be a transceiver, or an input/output interface.

In another implementation, the apparatus is a chip configured in the first network device. When the apparatus is a chip configured in the first network device, the communication interface may be an input/output interface.

In a fifth aspect, a processor is provided, which includes: input circuit, output circuit and processing circuit. The processing circuit is configured to receive signals through the input circuit and transmit signals through the output circuit, so that the processor performs the method of any one of the possible implementations of the above aspects.

In a specific implementation process, the processor may be a chip, the input circuit may be an input pin, the output circuit may be an output pin, and the processing circuit may be a transistor, a gate circuit, a flip-flop, various logic circuits, and the like. The input signal received by the input circuit may be received and input by, for example and without limitation, a receiver, the signal output by the output circuit may be output to and transmitted by a transmitter, for example and without limitation, and the input circuit and the output circuit may be the same circuit that functions as the input circuit and the output circuit, respectively, at different times. The specific implementation of the processor and various circuits are not limited in this application.

In a sixth aspect, an apparatus is provided that includes a processor and a memory. The processor is configured to read instructions stored in the memory and to receive signals via the receiver and transmit signals via the transmitter to perform the method of any one of the possible implementations of the aspects described above.

In one possible implementation, the processors are one or more, and the memories are one or more.

In one possible implementation, the memory may be integrated with the processor or provided separately from the processor.

In a specific implementation process, the memory may be a non-transitory (non-transitory) memory, such as a Read Only Memory (ROM), which may be integrated on the same chip as the processor, or may be separately disposed on different chips.

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

In a seventh aspect, a communication system is provided, which includes the foregoing terminal device and first network device.

In an eighth aspect, there is provided a computer program product comprising: a computer program (which may also be referred to as code, or instructions), which when executed, causes a computer to perform the method in any of the possible implementations of the aspects described above.

In a ninth aspect, a computer-readable storage medium is provided, which stores a computer program (which may also be referred to as code, or instructions) that, when executed on a computer, causes the computer to perform the method of any one of the possible implementations of the above aspects.

Drawings

Fig. 1 is a schematic diagram of a system architecture provided in an embodiment of the present application.

Fig. 2 is a schematic diagram of the format of S-NSSAI provided in an embodiment of the present application.

Fig. 3 is a schematic diagram of an example communication method according to an embodiment of the present application.

Fig. 4 is a schematic diagram of a format of cS-NSSAI provided in an embodiment of the present application.

Fig. 5 is a schematic diagram of a format of identification information of an AMF provided in an embodiment of the present application.

Fig. 6 is a schematic diagram of another communication method provided in the embodiment of the present application.

Fig. 7 is a schematic diagram of another communication method provided in the embodiment of the present application.

Fig. 8 is a schematic diagram of another communication method provided in the embodiment of the present application.

Fig. 9 is a schematic block diagram of a communication device provided in an embodiment of the present application.

Fig. 10 is another schematic block diagram of a communication device provided in an embodiment of the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be described below with reference to the drawings in the embodiments of the present application. Where in the description of the present application, "/" indicates a relationship where the objects associated before and after are an "or", unless otherwise stated, for example, a/B may indicate a or B; in the present application, "and/or" is only an association relationship describing an associated object, and means that there may be three relationships, for example, a and/or B, and may mean: a exists singly, A and B exist simultaneously, and B exists singly, wherein A and B can be singular or plural. Also, in the description of the present application, "a plurality" means two or more than two unless otherwise specified. "at least one of the following" or similar expressions refer to any combination of these items, including any combination of the singular or plural items. For example, at least one (one) of a, b, or c, may represent: a, b, c, a-b, a-c, b-c, or a-b-c, wherein a, b, c may be single or multiple. In addition, in order to facilitate clear description of technical solutions of the embodiments of the present application, in the embodiments of the present application, words such as "first" and "second" are used to distinguish identical items or similar items with substantially identical functions and actions. Those skilled in the art will appreciate that the terms "first," "second," and the like do not denote any order or importance, but rather the terms "first," "second," and the like do not denote any order or importance.

The technical scheme of the embodiment of the application can be applied to various communication systems, for example: new Radio (NR) in fifth generation (5th generation, 5g) mobile communication systems, future mobile communication systems, and the like.

Fig. 1 shows a schematic diagram of a network architecture applied to the present application. The network architecture is described from the perspective of a service interface, and may be composed of three parts, namely, a terminal device, a Public Land Mobile Network (PLMN), and a Data Network (DN), which are introduced below.

Terminal equipment 111 may also be referred to as User Equipment (UE). The terminal device 111 in this application is a device having a wireless transceiving function, and may communicate with one or more Core Network (CN) devices (also referred to as core devices) through an access network device (also referred to as an access device) in a Radio Access Network (RAN). Terminal device 111 can also be called an access terminal, subscriber unit, subscriber station, mobile, remote station, remote terminal, mobile device, user terminal, user agent, or user equipment, etc. Terminal device 111 may be deployed on land, including indoors or outdoors, hand-held or vehicle-mounted; can also be deployed on the water surface (such as a ship and the like); and may also be deployed in the air (e.g., airplanes, balloons, satellites, etc.).

Terminal device 111 may be a cellular telephone (cellular phone), a cordless telephone, a Session Initiation Protocol (SIP) phone, a smart phone (smart phone), a mobile phone (mobile phone), a Wireless Local Loop (WLL) station, a Personal Digital Assistant (PDA), or the like. Furthermore, the terminal device 111 may also be a handheld device with wireless communication functionality, a computing device or other device connected to a wireless modem, an in-vehicle device, a wearable device, a drone device or the internet of things, a terminal in the internet of vehicles, a terminal in any modality in a 5G network and future networks, a relay user equipment, or a terminal in a future evolved 6G network, etc. The relay user equipment may be, for example, a 5G home gateway (RG).

The terminal device 111 may also be a Virtual Reality (VR) terminal, an Augmented Reality (AR) terminal, a wireless terminal in industrial control (industrial control), a wireless terminal in self driving (self driving), a wireless terminal in remote medical (remote medical), a wireless terminal in smart grid, a wireless terminal in transportation safety, a wireless terminal in smart city (smart city), a wireless terminal in smart home (smart home), and the like. The embodiment of the present application does not limit the type or category of the terminal device.

The PLMN may include the following network functions: a network open function 101, a network storage function 102, a policy control function 103, a unified data management function 104, an authentication service function 107, an access and mobility management function 108, a session management function 109, a user plane function 113, a (wireless) access network 112, a network slice selection function 105, a network slice authentication and authorization function 110, etc., wherein a network composed of other functions in the PLMN except the (wireless) access network 112 may be referred to as CN.

The data network 114 may be generally deployed outside the PLMN, such as a third party network (of course, the DN may also be deployed inside the PLMN, which is not limited herein). Illustratively, the PLMN may have access to a plurality of data networks 114DN 120, and a plurality of services may be deployed on the data networks 114DN 120 to provide services such as data and/or voice services to the terminal device 110. For example, the data network 114 may be a private network of an intelligent plant, the sensors installed in the plant of the intelligent plant may be the terminal devices 111, and the control server of the sensors is deployed in the data network 114 and may provide services for the sensors. The sensor can communicate with the control server, obtain the instruction of the control server, transmit the sensor data gathered to the control server, etc. according to the instruction. For another example, the data network 114 may be an internal office network of a company, the mobile phone or computer of the employee of the company may be the terminal device 111, and the mobile phone or computer of the employee may access information, data resources, and the like on the internal office network of the company. The terminal device 111 may establish a connection with the PLMN through an interface (e.g., an N1 interface in fig. 1) provided by the PLMN, and use data and/or voice services provided by the PLMN. The terminal device 111 may also access the data network 114 via the PLMN, use operator services deployed on the data network 114, and/or services provided by third parties. The third party may be a service party other than the PLMN and the terminal device 111, and may provide services such as other data and/or voice for the terminal device 111. The specific expression form of the third party may be specifically determined according to an actual application scenario, and is not limited herein.

In a 5G communication system, the data network 114 may be a Data Network (DN). In future communication systems, the data network 114 may still be the DN, or may have another name, and the present application is not limited thereto.

The application function 106 is usually affiliated to a third party and not to the PLMN, but has a protocol relationship with the PLMN, and is usually used for performing application-influenced data routing and access network opening functions, performing policy control by interacting with a policy framework, and the like. Of course, the AF may also be deployed within the PLMN, which is not limited herein.

In the 5G communication system, the application function 106 may be an Application Function (AF) function. In future communication systems, the application function 106 may still be an AF, or may have another name, and the present application is not limited thereto.

The respective functions related to the PLMN will be described below.

1. (radio access network, (R) AN) 112: is a sub-network of the PLMN and is an implementation system between a service node (or network function) in the PLMN and the terminal device 111. The terminal device 111 accesses the PLMN, first via the (R) AN, and then connects to the service node in the PLMN via the (R) AN. The (R) AN in the embodiment of the present application may refer to the access network itself, or may refer to the access network device, which is not differentiated herein. AN access network device is a device that provides a wireless communication function for the terminal device 111, and may also be referred to as AN access device, AN (R) AN device, or a network device. The access network devices include, but are not limited to: next generation base station (gNB) in 5G system, evolved node B (eNB) in LTE system, radio Network Controller (RNC), node B (NB), base Station Controller (BSC), base Transceiver Station (BTS), home base station (home evolved node B, or home node B, HNB), base Band Unit (BBU), transmission and Reception Point (TRP), transmission Point (TP), small base station equipment (pico), mobile switching center, or network equipment in future network. It is understood that the present application is not limited to the specific type of access network device. In systems using different radio access technologies, the names of devices that function as access network devices may vary.

For example, in some deployments of access devices, the access devices may include Centralized Units (CUs), distributed Units (DUs), and so on. In other deployments of access devices, a CU may also be divided into a CU-Control Plane (CP), a CU-User Plane (UP), and so on. In some other deployments of the access device, the access device may also be an Open Radio Access Network (ORAN) architecture, and the application does not limit a specific deployment manner of the access device.

2. Network open function 101: for securely opening services and capabilities, etc. provided by the 3GPP network functions to the outside.

In the 5G communication system, the network open function 101 may be a network open function (NEF). In future communication systems, the network openness function 101 may still be NEF, or may have other names, and the present application is not limited thereto.

3. The network storage function 102, which is a control plane function provided by an operator, may be used to maintain real-time information of all network function services in the network.

In the 5G communication system, the network storage function 102 may be a network function (NRF). In future communication systems, the network storage function 102 may still be NRF, or may have other names, and the present application is not limited thereto.

4. The policy control function 103 is a control plane function provided by an operator, and supports a unified policy framework to manage network behavior, provide policy rules and subscription information related to policy decision to other control functions, and the like.

In a 5G communication system, the policy control function 103 may be a Policy Control Function (PCF). In future communication systems, the policy control function 103 may still be a PCF, or may have another name, which is not limited in this application.

5. Unified data management function 104: for handling subscriber identities, access authentication, registration, mobility management, etc.

In the 5G communication system, the unified data management function 104 may be Unified Data Management (UDM). In future communication systems, the unified data management function 104 may still be a UDM, or may have another name, which is not limited in this application.

6. An authentication service function 107 for performing a master authentication, i.e. an authentication between the terminal device and the operator network. After receiving the authentication request initiated by the subscriber, the authentication service function 107 may authenticate and/or authorize the subscriber through the authentication information and/or authorization information stored in the unified data management function, or generate the authentication and/or authorization information of the subscriber through the unified data management function. The authentication service function 107 may feed back authentication information and/or authorization information to the subscriber. In one implementation, the authentication service function 107 may also be combined with a unified data management function.

In a 5G communication system, the authentication service function 107 may be an authentication service function (AUSF). In future communication systems, the authentication service function 107 may still be AUSF, or may have another name, which is not limited in this application.

7. Access and mobility management function 108: the present invention is mainly used for mobility management, access management, and the like, and may be used to implement other functions, such as functions of lawful interception and access authorization/authentication, in addition to session management, in a Mobility Management Entity (MME) function.

In a 5G communication system, the access and mobility management function 108 may be an access and mobility management function (AMF). In future communication systems, the access and mobility management function 108 may still be an AMF, or may have another name, which is not limited in this application.

8. Session management function 109: the method is mainly used for session management, internet Protocol (IP) address allocation and management of terminal equipment, selection of a termination point capable of managing a user plane function, a policy control and charging function interface, downlink data notification and the like.

In the 5G communication system, the session management function 109 may be a Session Management Function (SMF). In future communication systems, the session management function 109 may still be SMF, or may have another name, which is not limited in this application.

9. User plane function 113: for packet routing and forwarding, quality of service (QoS) handling of user plane data, etc.

In a 5G communication system, the user plane function 113 may be a User Plane Function (UPF). In future communication systems, the user plane function 113 may still be a UPF, or may have other names, which is not limited in this application.

10. Network slice selection function 105: the control plane network function provided by the PLMN is used for determining a network slice example, selecting an access and mobility management function and the like.

In a 5G communication system, the network slice selection function 105 may be a Network Slice Selection Function (NSSF). In future communication systems, the network slice selection function 105 may still be NSSF, or may have other names, and the present application is not limited thereto.

11. Network slice authentication authorization function 110: is a control plane network function provided by the PLMN for supporting the slicing authentication of the terminal device with the data network.

In the 5G communication system, the network slice authentication and authorization function 110 may be a network slice authentication and authorization function (nsaaf). In future communication systems, the network slice authentication and authorization function 110 may still be NSSAAF, or may also have other names, which is not limited in this application.

In fig. 1, nnef, nausf, nnrf, npcf, numm, naf, namf, nsmf, nssf, nssaaf, N1, N2, N3, N4, and N6 are interface serial numbers. For example, the meaning of the above interface sequence number may refer to the meaning defined in the 3GPP standard protocol, and the application does not limit the meaning of the above interface sequence number. It should be noted that, in fig. 1, only the terminal device 111 is taken as an example for the UE, an interface name between each network function in fig. 1 is also only an example, and in a specific implementation, the interface name of the system architecture may also be other names, which is not limited in this application. It will be appreciated that each network function is only schematically depicted as one in fig. 1, and that in an actual network deployment there may be many, tens or hundreds of each network function or sub-network.

The network architecture diagram shown in fig. 1 can be understood as a service-based architecture in a non-roaming scenario. In the framework, different network functions are combined in order according to requirements of a specific scene, and customization of network capacity and service can be realized, so that special networks are deployed for different services, namely 5G network slicing (network slicing) is realized. The network slicing technology can enable an operator to respond to customer requirements more flexibly and quickly, and flexible allocation of network resources is supported.

For the purpose of understanding the embodiments of the present application, a brief description of the network and related terms referred to in the present application will be provided first. It should be noted that the second network device appearing below is deployed in the CN.

1. Network slicing

Network slicing is simply understood to cut an operator's physical network into a plurality of virtual end-to-end networks, each virtual network (including devices, access networks, transport networks, and core networks within the network) is logically independent, and a failure of any one virtual network does not affect the other virtual networks. In order to meet the diversity requirement and the isolation between slices, relatively independent management and operation and maintenance between services are required, and customized service functions and analysis capability are provided. Instances of different traffic types may be deployed on different network slices, as may different instances of the same traffic type. The network slice may be composed of a set of Network Functions (NF) and/or subnetworks, etc., for example, subnetworks (R) AN 112, AMF108, SMF 109, UPF 113 in fig. 1 may constitute one network slice. A plurality of network slices can be deployed in the PLMN, each network slice can have different performance to meet the requirements of different applications and different vertical industries, and an operator can "tailor" one network slice according to the requirements of customers of different vertical industries.

2. Network slice selection assistance information set (NSSAI)

NSSAI may be a list including one or more S-NSSAIs in a table.

3、S-NSSAI

An S-NSSAI is used to identify a network slice (or network slice type), and it is also understood that an S-NSSAI is identification information of a slice.

It should be understood that the network slice may also be referred to as a slice, a network slice example, or S-NSSAI, etc., and the name of the network slice is not limited in this application, and the slice, the network slice example, and the S-NSSAI have the same meaning and may be replaced with each other without specific description.

The format of S-NSSAI can be as shown in fig. 2, and it can be seen that one S-NSSAI can include two parts, which are: the slice type or service type (SST) is used to distinguish different characteristics of a network slice in terms of features, services, and the like, and the number of bits occupied by the SST may be 32, and the number of bits occupied by the SD may be 8.

When the terminal device needs to access one or more network slices, a request message may be sent to the RAN, for example, the terminal device may send a request message to the RAN at an access stratum (AS layer), where the request message carries NSSAI, and the NSSAI includes S-NSSAI of the one or more network slices, so that the RAN selects a correct second network device (capable of serving a network slice requested to be accessed by the terminal device) for the terminal device according to the NSSAI in the request message.

Carrying the S-NSSAI in the request message at the AS layer has at least the following two benefits:

1. the S-NSSAI is carried in the request message of the AS layer, so that the RAN can select a correct second network device for the terminal device, and if the RAN selects an incorrect (unable to serve the network slice requested to be accessed by the terminal device) second network device, in this case, after the terminal device establishes a connection with the second network device and authenticates each other, it will be discovered that the second network device is an incorrect second network device, and then an additional procedure, that is, a redirection (re-association) procedure, will be executed between the second network device and the terminal device, so AS to transfer information of the established connection, the context of the terminal device stored in the second network device, and the like to another second network device capable of serving the network slice requested to be accessed by the terminal device, and it can be seen that the redirection procedure not only increases the time delay, but also consumes additional signaling resources, and affects the user experience.

Therefore, the problem that the time delay is increased and the signaling resource is consumed due to the redirection process can be effectively solved by selecting the correct second network device for the terminal device, and the user experience is improved.

2. The S-NSSAI is carried in the request message of the AS layer, so that the RAN can know the S-NSSAI of the network slice currently requested to be accessed by the terminal device, and when the CN issues a congestion control instruction based on the network slice, the RAN can perform congestion control on the corresponding terminal device (the terminal device that has been accessed or is requesting to access the network slice), thereby dynamically optimizing the network performance of the network slice.

However, not all S-NSSAIs may be sent with the request message. It should be noted that the request message is sent before the secure connection is established between the terminal device and the RAN, that is, the information in the request message is sent in plaintext (cannot be encrypted), and when the S-NSSAI sent in plaintext risks leaking the sensitive information of the network slice, the terminal device cannot send the S-NSSAI in the AS layer because the S-NSSAI is easily heard by an eavesdropper, so AS to obtain the sensitive information, in other words, only the S-NSSAI that does not leak the sensitive information of the network slice can be carried in the request message of the AS layer in plaintext and sent to the RAN.

For example, for some network slices serving a particular system, for example, a police system, if an eavesdropper can eavesdrop the S-NSSAI of a network slice sent by a terminal device, the network slice serving the police system can be known according to the S-NSSAI of the network slice, so that the user of the terminal device can be known to be a member of the police system.

In view of this, the present application provides a communication method, for a network slice that may cause sensitive information to be leaked if S-NSSAI is sent in an access layer, the method can improve a possibility that a RAN selects a correct second network device for the network slice on the premise of avoiding leakage of the sensitive information of the network slice, and in addition, the method can also enable the RAN to perform congestion control for a terminal device that requests to access or has accessed the network slice, thereby effectively reducing problems of increase in delay and consumption of signaling resources caused by a redirection procedure, improving user experience, and dynamically optimizing network performance of the network slice.

The following describes the communication method provided in the present application in detail. First, taking a first network device as a network device deployed in a RAN and a second network device as an AMF108 deployed in a CN as an example, the communication method 300 provided in this application is described with reference to fig. 3, but the embodiment of this application is not limited thereto. For convenience of description, the numbering of functions is omitted below, and for example, "AMF" means "AMF 108".

Step 301, a terminal device sends a first request message to a first network device, where the first request message requests to access a target network slice, and the first request message includes identification information of a network slice group to which the target network slice belongs and first identification information of the target network slice. Accordingly, the first network device receives the first request message from the terminal device.

In step 302, the first network device sends a second request message to the second network device in response to the first request message.

Step 303, the second network device sends a response message to the first network device, where the response message indicates that the second network device allows the terminal device to access the target network slice. Accordingly, the first network device receives a reply message from the second network device.

Step 304, the first network device sends a response message to the terminal device. Accordingly, the terminal device receives a reply message from the first network device.

For example, in step 301, when the terminal device wants to access one or more network slices (hereinafter referred to as "target network slices") of a certain cell, the terminal device may send a first request message to a first network device deployed in the cell, for example, the terminal device sends the first request message to the first network device at an access layer, and the first request message requests to access the target network slices.

For example, the terminal device may determine whether the S-NSSAI of the target network slice can be sent at the AS layer before sending the first request message, for example, the terminal device may determine whether the S-NSSAI of the target network slice can be sent at the AS layer in the following manners.

Mode 1

The PLMN may pre-configure, for the terminal device, whether the S-NSSAI of the target network slice may be sent in the AS layer, or the PLMN may send indication information to the terminal device, where the indication information indicates whether the S-NSSAI of the target network slice may be sent in the AS layer.

Mode 2

And the terminal equipment judges whether the S-NSSAI of the network slice can be sent at the AS layer or not according to whether the S-NSSAI of the target network slice contains sensitive information of the network slice or not. If the S-NSSAI contains sensitive information of the network slice, the S-NSSAI representing the target network slice can not be sent at the AS layer, and if the S-NSSAI does not contain sensitive information of the target network slice, the S-NSSAI representing the target network slice can be sent at the AS layer. For ease of description, the following convention is made for this application: if the S-NSSAI of one network slice contains the sensitive information of the network slice, the network slice is called a sensitive network slice by the application; if the S-NSSAI of a network slice does not contain sensitive information for the network slice, the network slice is referred to as a non-sensitive network slice.

Assuming that a terminal device requests to access 6 network slices deployed in the cell, for convenience of description, these 6 network slices are respectively denoted AS network slice 1, network slice 2, network slice 3, network slice 4, network slice 5, and network slice 6, and S-NSSAI of these 6 network slices are respectively denoted AS S-NSSAI1, S-NSSAI2, S-NSSAI3, S-NSSAI4, S-NSSAI5, and S-NSSAI6, where S-NSSAI3, S-NSSAI4, and S-NSSAI6 may be transmitted at the AS layer, in other words, S-NSSAI3, S-NSSAI4, and S-NSSAI6 do not contain sensitive information of the network slice, and S-NSSAI1, S-NSSAI2, and S-NSSAI5 may not be transmitted at the AS layer, in other words, S-NSSAI1, S-NSSAI2, and S-NSSAI5 contain sensitive information of the network slice.

According to whether the S-NSSAI of the target network slice can be sent in the access stratum, the terminal device may send the first request message in the following manners, and accordingly, the first network device may determine the AMF serving the target network slice in the following manners.

Mode 1

When the S-NSSAI of the target network slice may be sent in the access stratum, the terminal device may carry the first identification information of the target network slice in the first request message of the AS layer, and send the first request message to the first network device, where the first identification information is the S-NSSAI of the target network slice.

For example, the terminal device wants to access network slice 3, in which case the target network slice is network slice 3, the terminal device may carry S-NSSAI3 in the first request message and send the first request message to the first network device.

For another example, the terminal device wants to access network slice 3 and network slice 4, in which case the target network slice includes network slice 3 and network slice 4, and the terminal device may carry S-NSSAI3 and S-NSSAI4 in the first request message and send the first request message to the first network device.

After receiving the first request message, the first network device performs step 302, and in step 302, the first network device selects, according to the first identification information in the first request message, an AMF serving a target network slice for the terminal device, and sends a second request message to the AMF to request the AMF to allow the terminal device to access the target network slice.

For example, the first network device may obtain an association relationship, where the association relationship includes a correspondence between multiple S-NSSAIs and multiple AMFs, and determine, according to the association relationship and the first identification information, an AMF serving a target network slice, where the association relationship may be as shown in table one:

watch 1

S-NSSAI1	AMF3
		S-NSSAI2	AMF1
S-NSSAI3	AMF4
		S-NSSAI4	AMF2
S-NSSAI5	AMF3
		S-NSSAI6	AMF4

For example, the first request message carries S-NSSAI3, and the first network device determines, according to the association relationship between S-NSSAI3 and S-NSSAI3, AMF4 corresponding to S-NSSAI3 as AMF serving network slice 3, and then sends the second request message to AMF 4.

For example, the first request message carries S-NSSAI3 and S-NSSAI4, the first network device determines, according to the association relationship between S-NSSAI3 and S-NSSAI3, AMF4 corresponding to S-NSSAI3 as the AMF serving network slice 3, and then sends the second request message to AMF4, and the first network device determines, according to the association relationship between S-NSSAI4 and S-NSSAI4, AMF2 corresponding to S-NSSAI4 as the AMF serving network slice 4, and then sends the second request message to AMF 2.

In order to avoid that an eavesdropper knows that the terminal equipment is the special terminal equipment capable of using the sensitive network slice according to the S-NSSAI of the target network slice, so as to know the special identity of a user using the terminal equipment, the network slices in the PLMN can be grouped to obtain a plurality of network slice groups, and each network slice group can comprise both the sensitive network slice and the non-sensitive network slice.

When the S-NSSAI of the target network slice may not be sent in the access stratum, the terminal device may carry, in the first request message, the identification information of the network slice group to which the target network slice belongs, and send the first request message to the first network device, and the first network device may select, according to the identification information of the network slice group to which the target network slice belongs, an AMF serving the target network slice for the terminal device.

Because the network slice group to which the target network slice belongs includes a plurality of network slices, an eavesdropper does not know which network slice in the network slice group to which the target network slice belongs is a sensitive network slice, in other words, the eavesdropper does not know whether the target network slice belongs to the sensitive network slice, so that even if the eavesdropper eavesdrops the identification information of the network slice group, whether the target network slice to which the terminal device wants to access belongs to the sensitive network slice cannot be known, and the risk of revealing privacy information or sensitive information of a user of the terminal device or the terminal device is reduced.

In this application, the identification information of the network slice group to which the target network slice belongs may also be referred to as Network Slice Group Information (NSGI) or Network Slice Group ID (NSGI). The present application is described below by taking the identification information of the network slice group as NSGI.

For example, it is assumed that the 6 network slices requested to be accessed by the terminal device belong to 3 network slice groups, for convenience of description, the NSGI of the 3 network slice groups are respectively denoted as NSGI1, NSGI2, and NSGI3, and for example, the correspondence between the S-NSSAI of the 6 network slices and the 3 NSGI is shown in table two.

Watch two

S-NSSAI1	NSGI1
		S-NSSAI2	NSGI3
S-NSSAI3	NSGI2
		S-NSSAI4	NSGI1
S-NSSAI5	NSGI2
		S-NSSAI6	NSGI3

The terminal device may obtain NSGI of one or more network slice groups supported by the first network device, and when a network slice group supported by the first network device includes a network slice group to which a target network slice that the terminal device wants to access belongs, the terminal device may send a first request message to the first network device, where the first request message carries NSGI of the network slice group to which the target network slice belongs.

It is worth mentioning that, in the present application, a manner of obtaining, by the terminal device, the NSGI of the one or more network slice groups supported by the first network device, the correspondence between the multiple network slices requested to be accessed by the terminal device and the network slice groups to which the multiple network slices belong is not limited, for example, the NSGI of the one or more network slice groups supported by the first network device may be sent to the terminal device by the first network device through a broadcast message, and the correspondence between the multiple network slices requested to be accessed by the terminal device and the network slice groups to which the multiple network slices belong may be configured on the terminal device in advance by a PLMN, or the correspondence between the multiple network slices requested to be accessed by the terminal device and the network slice groups to which the multiple network slices belong may also be notified to the terminal device by a configuration update message sent to the terminal device by the PLMN.

For example, the terminal device wants to access network slice 1, at this time, the target network slice is network slice 1, and assuming that the first network device supports 3 network slice groups in total, and NSGI of the 3 network slice groups are NSGI1, NSGI2, and NSGI3, respectively, in this case, the terminal device may carry NSGI1 corresponding to network slice 1 in the first request message, and send the first request message to the first network device.

For another example, the terminal device wants to access network slice 2 and network slice 5, in which case, the target network slice includes network slice 2 and network slice 5, and in this case, the terminal device may carry NSGI3 corresponding to network slice 2 and NSGI2 corresponding to network slice 5 in the first request message, and send the first request message to the first network device.

After receiving the first request message, the first network device performs step 302, and in step 302, the first network device selects an AMF serving a target network slice for the terminal device according to the NSGI of the network slice group in the first request message, and sends a second request message to the AMF to request the AMF to allow the terminal device to access the target network slice.

For example, the first network device may obtain an association relationship between the NSGI and the AMF, where the association relationship may include a correspondence relationship between multiple NSGIs and multiple AMFs, and the first network device determines, according to the association relationship and an NSGI of a network slice group to which a target network slice belongs, the AMF serving the target network slice, and the association relationship may be as shown in table three:

watch III

For example, the first request message carries NSGI1, the first network device determines, according to the association relationship shown by NSGI1 and table three, one of AMF2 and AMF3 corresponding to NSGI1 as the AMF serving the network slice in the network slice group corresponding to NSGI1, for example, the first network device may select one of AMF2 and AMF3 in a blind selection manner or a random selection manner as the AMF serving the network slice in the network slice group corresponding to NSGI1, and then sends the second request message to the AMF.

For example, the first request message carries NSGI3 and NSGI2, the first network device determines, according to the association relationship shown by NSGI3, NSGI2 and table three, one of AMF1 and AMF4 corresponding to NSGI3 as the AMF serving the network slice in the network slice group corresponding to NSGI3, then sends the second request message to the AMF, determines one of AMF3 and AMF4 corresponding to NSGI2 as the AMF serving the network slice in the network slice group corresponding to NSGI2, and then sends the second request message to the AMF.

When the target network slice includes both a network slice that the S-NSSAI can transmit at the access stratum and a network slice that the S-NSSAI cannot transmit at the access stratum, for a network slice that the S-NSSAI can transmit at the access stratum, the terminal device may carry first identification information of the network slice in the first request message, where the first identification information is the S-NSSAI of the network slice, and for a network slice that the S-NSSAI cannot transmit at the access stratum, the terminal device may carry identification information of a network slice group to which the network slice belongs in the first request message, and transmit the first request message to the first network device.

For example, the terminal device wants to access network slice 1 and network slice 4, in which case, the target network slice includes network slice 1 and network slice 4, and the terminal device may carry NSGI1 and S-NSSAI4 corresponding to network slice 1 in the first request message and send the first request message to the first network device.

After receiving the first request message, the first network device executes step 302, and in step 302, the first network device selects, according to the NSGI1 in the first request message, an AMF serving as a network slice in a network slice group corresponding to the NSGI1 for the terminal device, and selects, according to the S-NSSAI4 in the first request message, an AMF serving as a network slice 4 for the terminal device.

For example, the first network device may determine, according to the association relationship shown in table one, AMF2 corresponding to S-NSSAI4 as the AMF serving network slice 4, and may determine, according to the association relationship shown in table three, one of AMF2 and AMF3 corresponding to NSGI1 as the AMF serving network slice in the network slice group corresponding to NSGI 1.

It should be noted that, in the present application, a one-to-one correspondence relationship may also be satisfied between the NSGI and the AMF, and if the correspondence relationship between the NSGI and the AMF is a one-to-one correspondence relationship, the first network device may select a unique AMF through the NSGI. For example, assuming that the above 6S-NSSAIs belong to 4 network slice groups, for convenience of description, the NSGI of the 4 network slice groups are respectively denoted as NSGI1, NSGI2, NSGI3, and NSGI4, and the correspondence between the S-NSSAI and the 4 NSGI of the 6 network slices may be as shown in table four.

Watch four

Combining the corresponding relationship shown in table one, the corresponding relationship between 4 NSGI and 4 AMF can be obtained, and as shown in table 5, it can be seen that the NSGI and AMF satisfy a one-to-one corresponding relationship.

Watch five

NSGI1	AMF2
		NSGI2	AMF3
NSGI3	AMF4
		NSGI4	AMF1

In other words, by setting the correspondence between the S-NSSAI and the NSGI of the network slice group, the association between the NSGI of the network slice group and the AMF serving as the target network slice may be changed, and in order to facilitate the first network device to select the AMF according to the NSGI, the PLMN may configure the correspondence between the NSGI and the S-NSSAI appropriately so that the NSGI and the AMF satisfy a one-to-one correspondence relationship, or, when the number of the NSGI is different from the number of the AMF, configure the correspondence between the NSGI and the S-NSSAI appropriately so that the NSGI and the AMF satisfy a one-to-one correspondence relationship as much as possible.

It should be noted that, the association relationships listed in the above tables one to five are only exemplary, and do not limit the present application, and in a specific implementation, for example, the association relationship corresponding to table two may include a plurality of S-NSSAIs, a plurality of NSGIs and a plurality of AMFs, the association relationship corresponding to table three may include a plurality of S-NSSAIs, a plurality of NSGIs and a plurality of AMFs, the association relationship corresponding to table four may include a plurality of S-NSSAIs, a plurality of NSGIs and a plurality of AMFs, and the association relationship corresponding to table five may include a plurality of S-NSSAIs, a plurality of NSGIs and a plurality of AMFs, for example, the association relationship shown in table six may be obtained after combining table four with table five.

Watch six

S-NSSAI1	AMF3	NSGI2
			S-NSSAI2	AMF1	NSGI4
S-NSSAI3	AMF4	NSGI3
			S-NSSAI4	AMF2	NSGI1
S-NSSAI5	AMF3	NSGI2
			S-NSSAI6	AMF4	NSGI3

Mode 2

In order to further reduce the risk of leakage of sensitive information of the network slice, no matter whether the S-NSSAI of the target network slice can be sent at the access stratum or not, the terminal device carries the first identification information of the target network slice and the NSGI of the network slice group to which the target network slice belongs in the first request message, and sends the first request message to the first network device.

In one implementation manner, the terminal device respectively carries the first identification information of the target network slice and the NSGI of the network slice group to which the target network slice belongs in the first request message, and sends the first request message to the first network device.

In another implementation manner, the terminal device carries the NSGI of the network slice group to which the target network slice belongs in the first identification information, carries the first identification information carrying the NSGI in the first request message, and sends the first request message to the first network device.

In the two implementation manners, when the S-NSSAI of the target network slice can be sent at the access stratum, the first identification information of the target network slice is the S-NSSAI of the target network slice; when the S-NSSAI of the target network slice may not be transmitted at the access stratum, the first identification information of the target network slice may be in the same format as the S-NSSAI of the target network slice, but the content is not completely the same or different.

For example, when the S-NSSAI of a network slice may not be transmitted at the access stratum, the first identification information of the network slice may be generated by:

modifying the values of a part of or all bits in the S-NSSAI of the network slice, for example, replacing bits originally taking a value of 0 in all or part of fields in the S-NSSAI of the network slice with 1, and replacing bits originally taking a value of 1 with 0.

In this application, the first identification information of the NSGI, which carries the network slice group to which the target network slice belongs, may be referred to as a customized S-NSSAI (cS-NSSAI), and when the S-NSSAI of the target network slice cannot be transmitted in an access stratum, the first identification information of the target network slice may be referred to as a pseudonymized S-NSSAI (pS-NSSAI).

It should be understood that, when the S-NSSAI of a network slice may not be sent in the access stratum, the foregoing loads the NSGI of the network slice group to which the target network slice belongs in the pS-NSSAI to generate the cS-NSSAI of the network slice, which is only an exemplary illustration and is not limited to this application, and in specific implementation, for a network slice to which the S-NSSAI may not be sent in the access stratum, the terminal device may also load the NSGI of the network slice group to which the network slice belongs in the S-NSSAI of the network slice, and modify the remaining bits except the NSGI in the S-NSSAI carrying the NSGI, and the modification may refer to the foregoing modification manner to generate the cS-NSSAI of the network slice, and for brevity, details are not described here again.

For example, the PLMN may configure a plurality of pS-NSSAIs for the terminal device in advance, and the terminal device may randomly select one pS-NSSAI from the plurality of pS-NSSAIs when in use, and use the selected pS-NSSAI as the pS-NSSAI of the target network slice. In addition, the pS-NSSAI of the target network slice can also be randomly generated by the terminal device according to the format of the S-NSSAI.

In order to ensure that the first network device can recognize that the pS-NSSAI generated for the sensitive network slice is not the true S-NSSAI of the network slice, when generating the pS-NSSAI for the sensitive network slice, the PLMN or the terminal device may ensure that the pS-NSSAI is not a valid S-NSSAI or is not used by the terminal device, or the PLMN may ensure that the pS-NSSAI is not an S-NSSAI used by the terminal device, or the PLMN or the terminal device may ensure that the pS-NSSAI is not a valid S-NSSAI based on the knowledge of the terminal device.

The format of cS-NSSAI is described below by taking the target network slice as a non-sensitive network slice as an example.

The format of cS-NSSAI may be as shown in fig. 4. It should be noted that the distribution of the NSGI in the cS-NSSAI of the network slice group to which the target network slice belongs shown in fig. 4 is only an exemplary illustration, and in a specific implementation, the NSGI of the network slice group to which the target network slice belongs may be carried in the SD portion in fig. 4, or may also be carried in the SST portion in fig. 4, where the NSGI may occupy all bits of the SST portion or only occupy partial bits of the SST portion, or may also be dispersed in the SST portion and the SD portion, and furthermore, the NSGI of the network slice group to which the target network slice belongs may be carried in n consecutive bits, or may also be carried in n randomly dispersed bits, where n is an integer greater than or equal to 1.

It is worth mentioning that when cS-NSSAI carries NSGI and S-NSSAI, it implies that cS-NSSAI is an implementation of a simple combination of NSGI and S-NSSAI.

It should be further noted that, the present application does not limit the specific format of the cS-NSSAI, and in a specific implementation, the length of the cS-NSSAI, i.e., the number of bits included, may be consistent with or greater than the length of the original S-NSSAI, for example, the NSGI may occupy unused bits or reserved (reserved) bits in the S-NSSAI, in which case, the length of the cS-NSSAI, i.e., the number of bits included, may be consistent with the length of the original S-NSSAI. The description herein of cS-NSSAI applies equally to sensitive network slices.

After receiving the first request message, the first network device performs step 302:

in an implementation manner, the first network device may first determine whether the first identification information carried in the first request message is an actual S-NSSAI of the target network slice, if it is determined that the first identification information carried in the first request message is an actual S-NSSAI of the target network slice, the first network device may determine, according to the S-NSSAI and/or an NSGI of a network slice group to which the target network slice belongs, an AMF serving the target network slice or a network slice in the network slice group to which the target network slice belongs, and if it is determined that the first identification information carried in the first request message is a pS-NSSAI corresponding to the target network slice, the first network device may determine, according to an NSGI of the network slice group to which the target network slice belongs, an AMF serving a network slice in the network slice group to which the target network slice belongs.

In another implementation, the first network device may determine, according to only the NSGI of the network slice group to which the target network slice belongs and carried in the first request message, the AMF serving the network slice in the network slice group to which the target network slice belongs, that is, in this implementation, the first network device may not need to determine whether the first identification information is a true S-NSSAI of the target network slice.

For example, the first network device may determine whether the first identification information carried in the first request message is the real S-NSSAI of the target network slice by:

mode 1

The PLMN may configure the plurality of pS-NSSAIs to the first network device in advance, for example, the PLMN configures the value ranges corresponding to the plurality of pS-NSSAIs to the first network device in advance. After receiving the first request message, the first network device may compare a value of the first identifier information carried in the first request message with a value range corresponding to multiple pS-NSSAIs configured in advance by the PLMN, and if the value of the first identifier information falls within the value range corresponding to the multiple pS-NSSAIs, the first network device may determine that the first identifier information carried in the first request message is not the true S-NSSAI of the target network slice but the pS-NSSAI of the target network slice.

Mode 2

The PLMN may configure a plurality of S-NSSAIs to the first network device in advance, and indicate that the first identification information of the first network device other than the plurality of S-NSSAIs all belong to pS-NSSAIs, for example, the PLMN configures a value range corresponding to the plurality of S-NSSAIs to the first network device in advance, and indicates that the first identification information whose value does not fall within the value range is pS-NSSAI. After receiving the first request message, the first network device may compare a value of the first identification information carried in the first request message with a value range corresponding to a plurality of S-NSSAIs configured in advance by the PLMN, and if the value of the first identification information does not fall within the value range corresponding to the plurality of pS-NSSAIs, the first network device may determine that the first identification information carried in the first request message is not the real S-NSSAI of the target network slice but the pS-NSSAI of the target network slice.

Mode 3

The first network device may compare the value of the first identification information carried in the first request message with the S-NSSAI of the network slice served by the first network device, and if the first identification information belongs to the S-NSSAI of the network slice served by the first network device, the first network device may determine that the first identification information is the real S-NSSAI of the target network slice, whereas if the first identification information does not belong to the S-NSSAI of the network slice served by the first network device, the first network device may determine that the first identification information is not the real S-NSSAI of the target network slice but is the pS-NSSAI of the target network slice.

First, the first identification information of the target network slice and the NSGI of the network slice group to which the target network slice belongs are respectively carried in the first request message, and the cases of step 302 are described below by taking as an example.

In case 1, the first identification information of the target network slice may not be sent at the access stratum, and the first request message carries the NSGI of the network slice group to which the target network slice belongs and the pS-NSSAI of the target network slice.

For example, the terminal device wants to access network slice 2, in which case the target network slice is network slice 2, since the S-NSSAI of the target network slice may not be sent at the access stratum, in which case the terminal device may carry the pS-NSSAI corresponding to the target network slice and NSGI3 (known from table two) of the network slice group to which the target network slice belongs in the first request message, and send the first request message to the first network device.

The first network device may determine that the first identification information carried in the first request message is not a true S-NSSAI, but a pS-NSSAI, in which case the first network device may determine, according to the NSGI3 of the network slice group to which the target network slice belongs, an AMF serving a network slice in the network slice group to which the target network slice belongs.

For example, the first network device may determine, according to the association relationship shown in table three, one of AMF1 and AMF4 corresponding to NSGI3 as the AMF serving the network slice in the network slice group corresponding to NSGI 3.

In addition, the first network device may also determine, according to the NSGI3, the AMF serving the network slice in the network slice group corresponding to the NSGI3 without determining whether the first identification information is the true S-NSSAI.

In case 2, the S-NSSAI of the target network slice may be sent at the access stratum, and the first request message carries the NSGI of the network slice group to which the target network slice belongs and the S-NSSAI of the target network slice.

For example, the terminal device wants to access network slice 4, in which case the target network slice is network slice 4, since the S-NSSAI of the target network slice may be sent at the access layer, in which case the terminal device may carry the S-NSSAI4 of the target network slice and NSGI1 (known from table two) of the network slice group to which the target network slice belongs in the first request message, and send the first request message to the first network device.

The first network device may determine that the S-NSSAI4 carried in the first request message is a true S-NSSAI, in which case the first network device may determine the AMF serving the target network slice according to the S-NSSAI4.

For example, the first network device may determine, according to the association relationship shown in table one, AMF2 corresponding to S-NSSAI4 as the AMF serving the target network slice.

In addition, the first network device may further determine, according to the NSGI1 (known from the table two), which is in the network slice group to which the target network slice belongs, the AMF serving the network slice in the network slice group corresponding to the NSGI 1.

For example, the first network device may determine, according to the association relationship shown in table three, one of AMF2 and AMF3 corresponding to NSGI1 as the AMF serving the network slice in the network slice group corresponding to NSGI 1.

In addition, the first network device may further determine, according to the S-NSSAI4 and NSGI1 (known from table two) of the network slice group to which the target network slice belongs, an AMF serving the target network slice.

For example, the first network device may determine, according to the association relationships shown in tables one to three, AMF2 corresponding to both S-NSSAI4 and NSGI1 as the AMF serving the target network slice.

In case 3, the target network slice includes both a network slice that the S-NSSAI may send at the access stratum and a network slice that the S-NSSAI may not send at the access stratum, and for a network slice that the S-NSSAI may send at the access stratum, the first request message may carry the S-NSSAI of the target network slice and the NSGI of the network slice group to which the target network slice belongs, and for a network slice that the S-NSSAI may not send at the access stratum, the first request message may carry the pS-NSSAI of the target network slice and the NSGI of the network slice group to which the target network slice belongs.

For example, the terminal device wants to access network slice 2 and network slice 4, in which case the target network slice includes network slice 2 and network slice 4, the terminal device may carry S-NSSAI4 and NSGI1 (known in conjunction with table two) in the first request message, carry pS-NSSAI and NSGI3 (known in conjunction with table two) corresponding to S-NSSAI2 in the first request message, and send the first request message to the first network device.

After receiving the first request message, the first network device performs step 302, and please refer to the foregoing related description for a specific method for determining the AMF serving network slice 4 and the AMF serving network slice 2 by the first network device, which is not described herein again for brevity.

Next, taking the NSGI of the network slice group to which the target network slice belongs as an example to be borne in the first identification information, the case of step 302 will be described.

In case 1, the S-NSSAI of the target network slice may not be sent at the access stratum, the first request message carries the cS-NSSAI, the cS-NSSAI carries the NSGI of the network slice group to which the target network slice belongs, and information carried by the remaining bits of the cS-NSSAI except the NSGI is not the true S-NSSAI of the target network slice.

For example, the terminal device wants to access network slice 2, in which case the target network slice is network slice 2, since the S-NSSAI of the target network slice may not be sent at the access stratum, in which case the terminal device may bear cS-NSSAI corresponding to the target network slice in the first request message and send the first request message to the first network device, the cS-NSSAI bears NSGI1 (known by referring to table two) of the network slice group to which the target network slice belongs, and the remaining bits in the cS-NSSAI except for NSGI1 carry information that is not the true S-NSSAI of the target network slice.

The first network device may determine that information carried by remaining bits of the cS-NSSAI carried in the first request message, except for the NSGI1, is not the true S-NSSAI of the target network slice, and in this case, the first network device may determine, according to the NSGI1 of the network slice group to which the target network slice belongs, the AMF serving a network slice in the network slice group corresponding to the NSGI 1.

In case 2, the S-NSSAI of the target network slice may be sent at the access stratum, the first request message carries cS-NSSAI, the cS-NSSAI carries NSGI of the network slice group to which the target network slice belongs, and information carried by the remaining bits of the cS-NSSAI except for the NSGI is the real S-NSSAI of the target network slice.

For example, the terminal device wants to access network slice 4, in which case the target network slice is network slice 4, since the S-NSSAI of the target network slice may be sent at the access layer, in this case, the terminal device may load the cS-NSSAI corresponding to the target network slice in the first request message, and send the first request message to the first network device, where the cS-NSSAI carries NSGI1 of the network slice group to which the target network slice belongs (as can be known from table two), and the remaining bits in the cS-NSSAI except for NSGI1 are the real S-NSSAI of the target network slice, in other words, the information carried by the remaining bits in the cS-NSSAI except for NSGI1 is S-NSSAI4.

In this case, the first network device may determine the AMF serving the target network slice according to S-NSSAI4.

For example, the first network device may determine one of AMF2 and AMF3 corresponding to S-NSSAI4 and NSGI1 as the AMF serving the target network slice according to the association relationships shown in tables one to three.

In case 3, the target network slice includes both a network slice that the S-NSSAI may send at the access layer and a network slice that the S-NSSAI may not send at the access layer, for the network slice that the S-NSSAI may send at the access layer, the first request message carries the cS-NSSAI, the cS-NSSAI carries the NSGI of the network slice group to which the target network slice belongs, and information carried by remaining bits of the cS-NSSAI other than the NSGI is the true S-NSSAI of the target network slice, for the network slice that the S-NSSAI may not send at the access layer, the first request message carries the cS-NSSAI, the cS-NSSAI carries the NSGI of the network slice group to which the target network slice belongs, and information carried by remaining bits of the cS-NSSAI other than the NSGI is not the true S-NSSAI of the target network slice.

For example, the terminal device wants to access network slice 2 and network slice 4, in this case, the target network slice includes network slice 2 and network slice 4, the terminal device may carry cS-NSSAI of network slice 2 and cS-NSSAI of network slice 4 in the first request message, and send the first request message to the first network device, NSGI3 of the network slice group to which the target network slice belongs is carried in cS-NSSAI of network slice 2 (as known in table two), information carried by the remaining bits except NSGI3 in cS-NSSAI of network slice 2 is real S-NSSAI that is not network slice 2, NSGI1 of the network slice group to which the target network slice belongs is carried in cS-NSSAI of network slice 4 (as known in table two), and information carried by the remaining bits except NSGI1 in cS-NSSAI of network slice 4 is S-sansi 4.

After receiving the first request message, the first network device performs step 302, please refer to the related description above regarding the specific method for the first network device to determine the AMF serving network slice 4 and determine the AMF serving network slice 2, and for brevity, the description is omitted here.

It should be noted that the foregoing description about the AMF determined by the first network device to serve as the target network slice is only used as an exemplary illustration, and in the present application, the first network device may also determine the AMF to serve as the target network slice in the following several ways.

Illustratively, the PLMN may associate the NSGI with the AMF when generating the NSGI.

For example, the PLMN may bear the identification information of the AMF in the NSGI when defining the NSGI, so that the first network device may obtain the identification information of the AMF according to the NSGI bearing the identification information of the AMF, and further determine the corresponding AMF according to the identification information of the AMF.

For example, the identification information of the AMF may include at least one of an identification of an area where the AMF is located, an identification of a network device Set to which the AMF belongs, and a pointer of the AMF, and when the identification of the area where the AMF is located may be an AMF area ID (Region ID), the identification of the network device Set to which the AMF belongs may be an AMF Set ID (Set ID), the pointer of the AMF may be an AMF pointer, and the format of the identification information of the AMF may be as shown in fig. 5.

In fig. 5, it is assumed that the AMF area ID occupies 8 bits, the AMF set ID occupies 10 bits, and the AMF pointer occupies 6 bits, in this case, when the PLMN defines the NSGI format, the bits occupied by the NSGI may be greater than 24 bits, so that the NSGI may have enough bits to carry the identification information of the AMF.

In addition, while the PLMN carries the identification information of the AMF in the NSGI, the PLMN may also optimize the format of the NSGI, for example, the PLMN may optimize the bit number occupied by the NSGI.

For example, it is assumed that a plurality of AMFs deployed in a PLMN correspond to 8 areas, correspond to 16 AMF sets, and correspond to 4 pointers, in this case, 8 AMF area IDs corresponding to the 8 areas may be represented by 3 bits, 16 set IDs corresponding to the 16 AMF sets may be represented by 4 bits, and 4 pointers may be represented by 2 bits, in this case, an AMF area ID in identification information of an AMF may occupy 3 bits, an AMF set ID may occupy 4 bits, and an AMF pointer may occupy 2 bits, and at this time, when an NSGI format is defined by the PLMN, only the bits occupied by an NSGI are required to be greater than 9 bits, and the identification information of the AMF may be carried. Compared to the NSGI occupying more than 24 bits, the format of the NSGI is optimized.

For another example, assuming that the PLMN does not distinguish areas, in other words, a plurality of AMFs deployed in the PLMN correspond to 1 area, in this case, the AMF area ID may not be carried in the NSGI.

For another example, assuming that the multiple AMFs deployed in the PLMN are not grouped, in this case, the AMF set ID may not be carried in the NSGI.

For another example, assuming that multiple AMFs deployed in a PLMN are grouped, but there is only one AMF in each AMF set, in this case, the AMF pointer may not be carried in the NSGI. It should be noted that the manner in which the first network device determines the AMF serving as the target network slice may be used alone, or may be used in combination with the aforementioned manners in which the first network device determines the AMF serving as the target network slice, which is not limited in this application.

After determining the AMF serving the target network slice, the first network device sends a second request message to the AMF serving the target network slice, and after receiving the second request message, if the terminal device is allowed to access the target network slice, the AMF may send a response message to the first network device, where the response message indicates that the AMF allows the terminal device to access the target network slice.

Step 304, the first network device sends a response message to the terminal device. Accordingly, the terminal device receives the reply message from the first network device.

And after receiving the response message, the terminal equipment continues to interact with the first network equipment and the AMF to complete the process of accessing the target network slice.

In this application, since the first network device has already received, from the terminal device, the NSGI of the network slice group to which the network slice that the terminal device wants to access belongs, in this case, the first network device knows the NSGI of the network slice group to which the target network slice that the terminal device currently accesses belongs, and therefore, when the AMF issues a congestion control instruction based on the NSGI of the network slice group, the first network device may perform congestion control on the terminal device, thereby dynamically optimizing the network performance of the target network slice.

On the other hand, when the AMF issues a congestion control instruction based on a network slice group corresponding to an NSGI, the first network device may perform congestion control on a new request message that the terminal device requests to access a network slice, that is, if the network slice group to which the network slice requested to be accessed by the new request message belongs is a network slice group corresponding to an NSGI that the AMF issues and needs to perform congestion control, the first network device may perform congestion control on the new request message, so as to dynamically optimize the network performance of the target network slice, where the new request message may be from the terminal device that sends the first request message in this application or another terminal device other than the terminal device.

The following describes a communication method 600 provided by the present application with reference to fig. 6, assuming that a terminal device is currently in a Radio Resource Control (RRC) idle state and a Connection Management (CM) idle state, and continues to use a first network device as a network device deployed in a RAN and a second network device as an example of an AMF deployed in a CN.

Step 601, the terminal device receives a broadcast message from the first network device, where the broadcast message carries the NSGI of one or more network slice groups supported by the first network device. Optionally, the broadcast message may also carry a correspondence between the multiple network slices and the NSGI of the network slice group to which the multiple network slices belong.

When the terminal device is currently in an RRC idle state or a CM idle state, the terminal device may periodically monitor broadcast messages of a cell where the terminal device is currently located and neighboring cells.

When the terminal device receives the broadcast message of the neighboring cell, it is assumed that the terminal device determines, according to the signal strength of the broadcast message, that the signal of the neighboring cell is stronger, and one or more NSGIs carried in the broadcast message include an NSGI of a network slice group to which a network slice that the terminal device wants to access belongs, at this time, the terminal device may perform a cell reselection procedure, in other words, the terminal device may perform a procedure of camping from a currently located cell to the neighboring cell, assuming that the terminal device successfully completes camping to the neighboring cell.

In step 602, the terminal device sends an RRC connection request message to the first network device.

When the terminal device wants to access the slice, the terminal device first needs to establish an RRC connection, so as to switch from an RRC idle state to an RRC connected state.

Step 603, the first network device sends an RRC connection setup message to the terminal device.

After receiving the RRC connection request message from the terminal device, the first network device establishes a bearer (bearer) for the terminal device, and sends an RRC connection establishment message to the first network device.

Step 604, the terminal device sends an RRC connection complete message to the first network device, where the RRC connection complete message requests to access the target network slice, and the RRC connection complete message includes the S-NSSAI of the target network slice or the NSGI of the network slice group to which the target network slice belongs. Accordingly, the first network device receives an RRC connection complete message from the terminal device.

After the RRC connection setup is completed, the terminal device may send an RRC connection complete message to the first network device, and the terminal device may request access to one or more network slices (hereinafter referred to as "target network slices") supported by the cell through the RRC connection complete message.

Before sending the RRC connection complete message, the terminal device may first determine whether the S-NSSAI of the target network slice may be sent in the access layer, and if the S-NSSAI of the target network slice may be sent in the access layer, the terminal device sends an RRC connection complete message to the first network device, where the RRC connection complete message carries the S-NSSAI of the target network slice; and if the S-NSSAI of the target network slice can not be sent in the access layer, the terminal equipment sends an RRC connection completion message to the first network equipment, wherein the RRC connection completion message carries the NSGI of the network slice group to which the target network slice belongs. The S-NSSAI of the target network slice in the method 600 corresponds to the first identification information of the target network slice in the method 300, the NSGI of the network slice group to which the target network slice belongs corresponds to the identification information of the network slice group to which the target network slice in the method 300 belongs, the RRC connection completion message corresponds to the first request message in the method 300, and for specific description of step 604, reference is made to related description in step 301, and details are not repeated here for brevity.

In step 605, the first network device sends a request message to the second network device in response to the RRC connection complete message. The request message in the method 600 corresponds to the second request message in the method 300, and for the specific description of step 605, reference is made to the related description in step 302, and for brevity, details are not repeated here.

Step 606, the second network device sends a response message to the first network device, where the response message indicates that the second network device allows the terminal device to access the target network slice. Accordingly, the first network device receives a reply message from the second network device. The response message in the method 600 corresponds to the response message in the method 300, and for the specific description of the step 606, please refer to the related description in the step 303, which is not described herein again for brevity.

Step 607, the first network device sends a response message to the terminal device. Accordingly, the terminal device receives the reply message from the first network device. For the detailed description of step 607, please refer to the related description in step 304, and for brevity, the detailed description is omitted here.

Based on the technical scheme, when the S-NSSAI of the target network slice can be sent at an access layer, the terminal equipment sends the S-NSSAI of the target network slice to the first network equipment, and the first network equipment can select the AMF for the target network slice according to the S-NSSAI; when the S-NSSAI of the target network slice cannot be sent at the access layer, the terminal device sends the NSGI of the network slice group to which the target network slice belongs to the first network device, and since the network slice group to which the target network slice belongs includes a plurality of network slices, it is unclear which network slice in the network slice group to which the target network slice belongs is the sensitive network slice by the eavesdropper, so that it is impossible to know whether the target network slice to which the terminal device intends to access belongs to the sensitive network slice even if the eavesdropper eavesdrops on the NSGI of the network slice group to which the target network slice belongs, and in addition, by sending the NSGI of the network slice group to which the target network slice belongs to the first network device, the first network device can select the AMF for the target network slice according to the NSGI of the network slice group to which the target network slice belongs and the correspondence between the NSGI and the AMF, in this case, the possibility of selecting the AMF capable of serving the target network slice to which the terminal device can request access can be increased.

Next, assuming that the terminal device is currently in an RRC idle state and a CM idle state, taking the first network device as a network device deployed in the RAN and the second network device as an AMF deployed in the CN as an example, the communication method 700 provided by the present application is introduced with reference to fig. 7.

In step 701, the terminal device receives a broadcast message from the first network device, where the broadcast message carries the NSGI of one or more network slice groups supported by the first network device. For a detailed description of step 701, please refer to the related description in step 601, and for brevity, the detailed description is omitted here.

In step 702, the terminal device sends an RRC connection request message to the first network device. For a detailed description of step 702, please refer to the related description in step 602, and for brevity, the detailed description is omitted here.

Step 703, the first network device sends an RRC connection setup message to the terminal device. For the detailed description of step 703, please refer to the related description in step 603, and for brevity, the description is omitted here.

Step 704, the terminal device sends an RRC connection complete message to the first network device, where the RRC connection complete message requests to access the target network slice, and the RRC connection complete message includes the S-NSSAI of the target network slice and the NSGI of the network slice group to which the target network slice belongs, or the RRC connection complete message includes the pS-NSSAI of the target network slice and the NSGI of the network slice group to which the target network slice belongs. Accordingly, the first network device receives an RRC connection complete message from the terminal device.

After the RRC connection setup is completed, the terminal device may send an RRC connection complete message to the first network device, and the terminal device may access one or more network slices (hereinafter referred to as "target network slices") supported by the cell through the RRC connection complete message.

Before sending the RRC connection complete message, the terminal device may first determine whether the S-NSSAI of the target network slice may be sent in the access layer, and if the S-NSSAI of the target network slice may be sent in the access layer, the terminal device sends the RRC connection complete message to the first network device, where the RRC connection complete message carries the S-NSSAI of the target network slice and the NSGI of the network slice group to which the target network slice belongs; and if the S-NSSAI of the target network slice cannot be sent in the access layer, the terminal equipment sends an RRC connection completion message to the first network equipment, wherein the RRC connection completion message carries the pS-NSSAI of the target network slice and the NSGI of the network slice group to which the target network slice belongs. The S-NSSAI of the target network slice in the method 700 or the pS-NSSAI of the target network slice corresponds to the first identification information of the target network slice in the method 300, the NSGI of the network slice group to which the target network slice in the method 700 belongs corresponds to the identification information of the network slice group to which the target network slice in the method 300 belongs, the RRC connection complete message in the method 700 corresponds to the first request message in the method 300, and for the specific description of step 704, please refer to the related description in step 301, and for brevity, it is not repeated herein.

Step 705, the first network device sends a request message to the second network device in response to the RRC connection complete message. The request message in the method 700 corresponds to the second request message in the method 300, and for the specific description of the step 705, please refer to the related description in the step 302, which is not described herein again for brevity.

Step 706, the second network device sends a response message to the first network device, where the response message indicates that the second network device allows the terminal device to access the target network slice. Accordingly, the first network device receives a reply message from the second network device. The response message in the method 700 corresponds to the response message in the method 300, and for the specific description of the step 706, please refer to the related description in the step 303, which is not described herein again for brevity.

In step 707, the first network device sends a response message to the terminal device. Accordingly, the terminal device receives the reply message from the first network device. For a detailed description of step 707, please refer to the related description in step 304, and for brevity, the detailed description is omitted here.

Based on the technical scheme, no matter whether the S-NSSAI of the target network slice can be sent in an access layer or not, the terminal device sends the first identification information of the target network slice and the NSGI of the network slice group to which the target network slice belongs to the first network device, when the S-NSSAI of the target network slice can be sent in the access layer, the first identification information of the target network slice is S-NSSAI, and when the S-NSSAI of the target network slice cannot be sent in the access layer, the first identification information of the target network slice is pS-NSSAI, wherein the target network slice pS-NSSAI and the target network slice S-NSSAI have the same format but have incompletely the same or completely different content.

In addition, by sending the NSGI of the network slice group to which the target network slice belongs to the first network device, the first network device may select the AMF for the target network slice according to the NSGI of the network slice group to which the target network slice belongs and the correspondence between the NSGI and the AMF. It should be noted that, in the present application, the first identification information is identifiable as to whether the first identification information is S-NSSAI corresponding to S-NSSAI of a non-sensitive network slice or pS-NSSAI corresponding to S-NSSAI of a sensitive network slice.

Next, assuming that the terminal device is currently in an RRC idle state and a CM idle state, taking the first network device as a network device deployed in the RAN and the second network device as an AMF deployed in the CN as an example, the communication method 800 provided by the present application is introduced with reference to fig. 8.

In step 801, a terminal device receives a broadcast message from a first network device, where the broadcast message carries the NSGI of one or more network slice groups supported by the first network device. For a detailed description of step 801, please refer to the related description in step 601, and for brevity, the description is omitted here.

In step 802, the terminal device sends an RRC connection request message to the first network device. For the detailed description of step 802, please refer to the related description in step 602, and for brevity, it is not repeated here.

Step 803, the first network device sends an RRC connection setup message to the terminal device. For the detailed description of step 803, please refer to the related description in step 603, and for brevity, the description is omitted here.

Step 804, the terminal device sends an RRC connection complete message to the first network device, where the RRC connection complete message requests to access the target network slice, the RRC connection complete message includes a cS-NSSAI of the target network slice, the cS-NSSAI carries an NSGI of a network slice group to which the target network slice belongs, and information carried by bits other than the NSGI in the cS-NSSAI is a real S-NSSAI of the target network slice, or the cS-NSSAI carries an NSGI of the network slice group to which the target network slice belongs, and information carried by bits other than the NSGI in the cS-NSSAI is not a real S-NSSAI of the target network slice. Accordingly, the first network device receives an RRC connection complete message from the terminal device.

After receiving the RRC connection setup message, the terminal device may establish an RRC connection with the first network device, and after the RRC connection setup is completed, the terminal device may send an RRC connection complete message to the first network device, and the terminal device may access one or more network slices (hereinafter referred to as "target network slices") supported by the cell through the RRC connection complete message.

Before sending the RRC connection complete message, the terminal device may first determine whether the S-NSSAI of the target network slice may be sent in an access layer, and if the S-NSSAI of the target network slice may be sent in the access layer, the terminal device sends the RRC connection complete message to the first network device, where the RRC connection complete message carries a cS-NSSAI of the target network slice, and the cS-NSSAI carries the S-NSSAI of the target network slice and an NSGI of a network slice group to which the target network slice belongs; if the S-NSSAI of the target network slice cannot be sent in the access layer, the terminal device sends an RRC connection completion message to the first network device, wherein the RRC connection completion message carries the NSGI of the network slice group to which the target network slice belongs, and the information carried by the bits of the cS-NSSAI except the NSGI is not the real S-NSSAI of the target network slice. The S-NSSAI of the target network slice in the method 800 or the non-true S-NSSAI of the target network slice corresponds to the first identification information of the target network slice in the method 300, the NSGI of the network slice group to which the target network slice in the method 800 belongs corresponds to the identification information of the network slice group to which the target network slice in the method 300 belongs, the cS-NSSAI of the method 800 corresponds to the first identification information of the method 300 that carries the identification information of the network slice group to which the target network slice belongs, the RRC connection complete message in the method 800 corresponds to the first request message in the method 300, and for the specific description of the step 804, reference is made to the related description in step 301, and for the sake of brevity, details are not repeated herein.

In step 805, the first network device sends a request message to the second network device in response to the RRC connection complete message. The request message in the method 800 corresponds to the second request message in the method 300, and for the detailed description of the step 805, please refer to the related description in the step 302, which is not described herein again for brevity.

In step 806, the second network device sends a response message to the first network device, where the response message indicates that the second network device allows the terminal device to access the target network slice. Accordingly, the first network device receives a reply message from the second network device. The response message in the method 800 corresponds to the response message in the method 300, and for the specific description of step 806, please refer to the related description in step 303, which is not described herein again for brevity.

In step 807, the first network device sends a response message to the terminal device. Accordingly, the terminal device receives the reply message from the first network device. For a detailed description of step 807, please refer to the related description in step 304, and for brevity, the detailed description is omitted here.

Based on the technical scheme, no matter whether the S-NSSAI of the target network slice can be sent in the access stratum or not, the terminal device sends the cS-NSSAI to the first network device, at this time, the first identification information is the cS-NSSAI, when the S-NSSAI of the target network slice can be sent in the access stratum, the cS-NSSAI carries the NSGI of the network slice group to which the target network slice belongs, and information carried by the remaining bits except the NSGI in the cS-NSSAI is the real S-NSSAI of the target network slice, when the S-NSSAI of the target network slice cannot be sent in the access stratum, the cS-NSSAI carries the NSGI of the network slice group to which the target network slice belongs, and information carried by the remaining bits except the NSGI in the cS-NSSAI is not the real S-NSSAI of the target network slice.

Since the terminal device transmits the cS-NSSAI to the first network device regardless of whether the S-NSSAI of the target network slice can be transmitted in the access layer, even if the eavesdropper overhears the cS-NSSAI, it cannot be determined whether the information carried by the bits other than the NSGI in the cS-NSSAI is the S-NSSAI of the non-sensitive network slice or the non-real S-NSSAI of the sensitive network slice, and therefore, the eavesdropper cannot know whether the target network slice to which the terminal device intends to access belongs to the sensitive network slice according to the information carried by the bits other than the NSGI in the cS-NSSAI, and further, since the network slice group to which the target network slice belongs includes a plurality of network slices, the eavesdropper cannot know which network slice group of the target network slice belongs to the sensitive network slice, and therefore, even if the eavesdropper overhears the cS-NSSAI, it cannot know whether the target network slice group to which the terminal device intends to access belongs to the sensitive network slice according to the network slice group of the target network slice.

In addition, by sending the NSGI of the network slice group to which the target network slice belongs to the first network device, the first network device may select the AMF for the target network slice according to the NSGI of the network slice group to which the target network slice belongs and the correspondence between the NSGI and the AMF. It should be noted that, in the present application, the first network device is identifiable as to whether the information carried by the remaining bits of the cS-NSSAI except the NSGI is the S-NSSAI of the non-sensitive network slice or the non-real S-NSSAI of the sensitive network slice.

It should be noted that, when the terminal device wants to access two or more network slices, the first network device may determine different AMFs for different network slices according to the above method. In addition, in further view of reducing complexity of using different AMFs, the first network device may select one AMF from the determined plurality of AMFs as an AMF serving the two or more network slices, and transmit a second request message for the two or more network slices to the AMF.

It should be noted that, the communication method provided by the present application is described above by taking S-NSSAI as an example, but the embodiment of the present application is not limited thereto, and the communication method provided by the present application may also be applied to identifiers of other slices, and in a specific implementation, for example, the S-NSSAI may also be replaced by an identifier (NSI-ID) of a network slice example.

It should be noted that the above communication method provided by the present application is only an exemplary one and is not a limitation of the present application, and any method obtained by replacing or recombining the above steps falls within the scope of the present application.

The communication method provided by the embodiment of the present application is described in detail above with reference to fig. 3 to 8. Hereinafter, a communication device according to an embodiment of the present application will be described in detail with reference to fig. 9 to 10.

Fig. 9 is a schematic block diagram of a communication device provided in an embodiment of the present application. As shown in fig. 9, the apparatus 900 may include a transceiving unit 910 and a processing unit 920.

In a possible design, the apparatus 900 may be the terminal device in the foregoing method embodiment, and may also be a module (e.g., a chip) applied to the terminal device. The apparatus 900 may be configured to perform the steps or processes corresponding to the terminal device in the methods 300 to 800.

Specifically, the transceiving unit 910 is configured to send a first request message to a first network device, where the first request message requests to access a target network slice, and the first request message includes identification information of a network slice group to which the target network slice belongs and first identification information of the target network slice, and the transceiving unit 910 is further configured to receive a response message from the first network device, where the response message indicates that a second network device allows the communication apparatus to access the target network slice.

Optionally, the identification information of the network slice group to which the target network slice belongs is carried in the first identification information of the target network slice.

Optionally, the identification information of the second network device is carried in the identification information of the network slice group to which the target network slice belongs.

Optionally, the identification information of the second network device includes at least one of an identification of an area corresponding to the second network device, an identification of a network device set to which the second network device belongs, and a pointer corresponding to the second network device.

Optionally, the first identification information of the target network slice is generated by modifying the S-NSSAI of the target network slice.

Optionally, the second network device is an AMF.

In another possible design, the apparatus 900 may be the first network device in the foregoing method embodiment, and may also be a module (e.g., a chip) applied to the first network device. The apparatus 900 may be configured to perform the steps or processes corresponding to the first network device in the methods 200 to 1300.

Specifically, the transceiving unit 910 is configured to: the processing unit 920 is configured to receive a first request message from a terminal device, where the first request message requests access to a target network slice, and the first request message includes identification information of a network slice group to which the target network slice belongs and first identification information of the target network slice, and send a second request message to a second network device in response to the first request message; the transceiving unit 910 is further configured to receive a response message from the second network device, where the response message indicates that the second network device allows the terminal device to access the target network slice, and the transceiving unit 910 is further configured to send the response message to the terminal device.

Optionally, the transceiving unit 910 is further configured to: acquiring association information, where the association information includes a correspondence between identification information of a network slice group to which the target network slice belongs and the second network device, and/or the association information includes a correspondence between the first identification information and the second network device, and the processing unit 920 is specifically configured to: and sending a second request message to the second network equipment according to at least one item of the identification information of the network slice group to which the target network slice belongs, the first identification information and the association information.

Optionally, the identification information of the second network device is carried in the identification information of the network slice group to which the target network slice belongs, and the processing unit 920 is specifically configured to: and sending the second request message to the second network equipment according to the identification information of the second network equipment.

Optionally, the identification information of the network slice group to which the target network slice belongs is carried in the first identification information.

Optionally, the first identification information of the target network slice is generated after S-NSSAI modification of the target network slice.

Optionally, the second network device is an AMF.

It should be appreciated that the apparatus 900 herein is embodied in the form of a functional unit. The term unit herein may refer to an Application Specific Integrated Circuit (ASIC), an electronic circuit, a processor (e.g., a shared, dedicated, or group processor), and memory that execute one or more software or firmware programs, a combinational logic circuit, and/or other suitable components that support the described functionality. In an optional example, it may be understood by those skilled in the art that the apparatus 900 may be specifically a terminal device in the foregoing embodiment, and may be configured to execute each procedure and/or step corresponding to the terminal device in the foregoing embodiment of the method, or the apparatus 900 may be specifically a first network device in the foregoing embodiment, and may be configured to execute each procedure and/or step corresponding to the first network device in the foregoing embodiment of the method, and details are not described herein again to avoid repetition.

The apparatus 900 of each of the above-mentioned schemes has a function of implementing corresponding steps executed by the terminal device in the above-mentioned method, or the apparatus 900 of each of the above-mentioned schemes has a function of implementing corresponding steps executed by the first network device in the above-mentioned method. The functions can be realized by hardware, and the functions can also be realized by executing corresponding software by hardware. The hardware or software comprises one or more modules corresponding to the functions; for example, the communication unit may be replaced by a transceiver (for example, the transmitting unit in the communication unit may be replaced by a transmitter, and the receiving unit in the communication unit may be replaced by a receiver), and other units, such as a processing unit and the like, may be replaced by a processor, to respectively perform the transceiving operation and the related processing operation in each method embodiment.

Furthermore, the communication unit may also be a transceiver circuit (for example, may include a receiving circuit and a transmitting circuit), and the processing unit may be a processing circuit.

Fig. 10 illustrates a communication apparatus 1000 provided in an embodiment of the present application. The apparatus 1000 includes a processor 1010 and a transceiver 1020. Wherein, the processor 1010 and the transceiver 1020 communicate with each other through the internal connection path, and the processor 1010 is configured to execute instructions to control the transceiver 1020 to transmit and/or receive signals.

Optionally, the apparatus 1000 may further include a memory 1030, the memory 1030 and the processor 1010, the transceiver 1020 being in communication with each other via an internal connection. The memory 1030 is configured to store instructions, and the processor 1010 is configured to execute the instructions stored in the memory 1030. In a possible implementation manner, the apparatus 1000 is configured to implement each flow and step corresponding to the terminal device in the foregoing method embodiment. In another possible implementation manner, the apparatus 1000 is configured to implement the respective flows and steps corresponding to the first network device in the foregoing method embodiment.

It should be understood that the apparatus 1000 may be embodied as the terminal device, the first network device in the foregoing embodiments, and may also be a chip or a chip system. Correspondingly, the transceiver 1020 may be a transceiver circuit of the chip, which is not limited herein. Specifically, the apparatus 1000 may be configured to perform each step and/or flow corresponding to the terminal device or the first network device in the foregoing method embodiments. Alternatively, the memory 1030 may include both read-only memory and random access memory, and provide instructions and data to the processor. The portion of memory may also include non-volatile random access memory. For example, the memory may also store device type information. The processor 1010 may be configured to execute instructions stored in the memory, and when the processor 1010 executes the instructions stored in the memory, the processor 1010 is configured to perform the steps and/or processes of the above-described method embodiments corresponding to the terminal device or the first network device. In implementation, the steps of the above method may be performed by integrated logic circuits of hardware in a processor or by instructions in the form of software. The steps of a method disclosed in connection with the embodiments of the present application may be directly implemented by a hardware processor, or may be implemented by a combination of hardware and software modules in a processor. The software modules may be located in ram, flash, rom, prom, or eprom, registers, etc. as is well known in the art. The storage medium is located in a memory, and a processor reads information in the memory and completes the steps of the method in combination with hardware of the processor. To avoid repetition, it is not described in detail here.

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

It will be appreciated that the memory in the embodiments of the subject application can be either volatile memory or nonvolatile memory, or can include both volatile and nonvolatile memory. The non-volatile memory may be a read-only memory (ROM), a Programmable ROM (PROM), an Erasable PROM (EPROM), an Electrically Erasable PROM (EEPROM), or a flash memory. Volatile memory can be Random Access Memory (RAM), which acts as external cache memory. By way of example, but not limitation, many forms of RAM are available, such as Static Random Access Memory (SRAM), dynamic Random Access Memory (DRAM), synchronous Dynamic Random Access Memory (SDRAM), double data rate SDRAM, enhanced SDRAM, SLDRAM, synchronous Link DRAM (SLDRAM), and direct rambus RAM (DR RAM). It should be noted that the memory of the systems and methods described herein is intended to comprise, without being limited to, these and any other suitable types of memory.

According to the method provided by the embodiment of the present application, the present application further provides a computer program product, which includes: computer program code which, when run on a computer, causes the computer to perform the various steps or procedures performed by the terminal device or the first network device in the embodiments shown in fig. 3 to 8.

According to the method provided by the embodiment of the present application, a computer-readable storage medium is further provided, where the computer-readable storage medium stores program codes, and when the program codes are executed on a computer, the computer is caused to execute the steps or processes executed by the terminal device or the first network device in the embodiments shown in fig. 2 to 8.

According to the method provided by the embodiment of the application, the application also provides a communication system which can comprise the terminal equipment and the first network equipment.

The embodiments shown in fig. 3 to 8 in the above-described respective apparatus embodiments and method embodiments fully correspond, and the respective steps are performed by respective modules or units, for example, a communication unit (transceiver) performs the steps of receiving or transmitting in the method embodiments, and other steps besides transmitting and receiving may be performed by a processing unit (processor). The function of a particular element may be based on the corresponding method embodiment. The number of the processors may be one or more.

In the embodiments of the present application, each term and english abbreviation is an exemplary example given for convenience of description and should not be construed as limiting the present application in any way. This application is not intended to exclude the possibility that other terms may be defined in existing or future protocols to carry out the same or similar functions.

In the embodiments of the present application, the first, second and various numerical numbers are only used for convenience of description and are not used to limit the scope of the embodiments of the present application. For example, different core network devices are distinguished, different attribute information is distinguished, and the like.

As used in this specification, the terms "component," "module," "system," and the like are intended to refer to a computer-related entity, either hardware, firmware, a combination of hardware and software, or software in execution. For example, a component may be, but is not limited to being, a process running on a processor, an object, an executable, a thread of execution, a program, and/or a computer. By way of illustration, both an application running on a computing device and the computing device can be a component. One or more components can reside within a process and/or thread of execution and a component may be localized on one computer and/or distributed between two or more computers. In addition, these components can execute from various computer readable storage media having various data structures stored thereon. The components may communicate by way of local and/or remote processes such as in accordance with a signal having one or more data packets (e.g., data from two components interacting with one another at a local system, distributed system, and/or across a network such as the internet with other systems by way of the signal).

It is to be understood that "at least one" as used herein refers to one or more, "a plurality" refers to two or more. "and/or" describes the association relationship of the associated object, indicating that there may be three relationships, for example, a and/or B, which may indicate: a exists alone, A and B exist simultaneously, and B exists alone, wherein A and B can be singular or plural. The character "/" generally indicates that the former and latter associated objects are in an "or" relationship. "at least one of the following" or similar expressions refer to any combination of these items, including any combination of the singular or plural items. For example, at least one (one) of a, b, and c, may represent: a, or b, or c, or a and b, or a and c, or b and c, or a, b and c, wherein a, b and c can be single or multiple.

Those of ordinary skill in the art will appreciate that the various illustrative logical blocks and steps (step) described in connection with the embodiments disclosed herein may be implemented as electronic hardware or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the technical solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

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

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

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 on multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, functional units in the embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit.

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

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

The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily think of the changes or substitutions within the technical scope of the present application, and shall be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A method of communication, comprising:

a terminal device sends a first request message to a first network device, wherein the first request message requests to access a target network slice, and the first request message comprises identification information of a network slice group to which the target network slice belongs and first identification information of the target network slice;

the terminal device receives a response message from the first network device, wherein the response message indicates that the second network device allows the terminal device to access the target network slice.

2. The method of claim 1, wherein identification information of a network slice group to which the target network slice belongs is carried in the first identification information of the target network slice.

3. The method according to claim 1 or 2, wherein the identification information of the second network device is carried in the identification information of the network slice group to which the target network slice belongs.

4. The method of claim 3, wherein the identification information of the second network device comprises at least one of an identification of an area corresponding to the second network device, an identification of a set of network devices to which the second network device belongs, and a pointer corresponding to the second network device.

5. The method according to any of claims 1 to 4, wherein the first identification information of the target network slice is generated by modifying single network slice selection assistance information S-NSSAI of the target network slice.

6. The method according to any of claims 1 to 5, wherein the second network device is an Access and mobility management function, AMF.

7. A method of communication, comprising:

a first network device receives a first request message from a terminal device, wherein the first request message requests to access a target network slice, and the first request message comprises identification information of a network slice group to which the target network slice belongs and first identification information of the target network slice;

in response to the first request message, the first network device sending a second request message to a second network device;

the first network device receiving a response message from the second network device, the response message indicating that the second network device allows the terminal device to access the target network slice;

and the first network equipment sends the response message to the terminal equipment.

8. The method of claim 7, further comprising:

the first network device obtains associated information, where the associated information includes a correspondence between identification information of a network slice group to which the target network slice belongs and the second network device, and/or the associated information includes a correspondence between the first identification information and the second network device;

the sending, by the first network device to a second network device in response to the first request message, a second request message includes:

and the first network equipment sends a second request message to the second network equipment according to at least one item of the identification information and the first identification information of the network slice group to which the target network slice belongs and the associated information.

9. The method according to claim 7 or 8, wherein identification information of the second network device is carried in identification information of a network slice group to which the target network slice belongs, and the sending, by the first network device, a second request message to the second network device in response to the first request message comprises:

and the first network equipment sends the second request message to the second network equipment according to the identification information of the second network equipment.

10. The method of claim 9, wherein the identification information of the second network device comprises at least one of an identification of an area corresponding to the second network device, an identification of a set of network devices to which the second network device belongs, and a pointer corresponding to the second network device.

11. The method according to any of claims 7 to 10, wherein identification information of a network slice group to which the target network slice belongs is carried in the first identification information.

12. The method according to any of claims 7 to 11, wherein the first identification information of the target network slice is generated after S-NSSAI modification of the target network slice.

13. The method according to any of claims 7 to 12, wherein the second network device is an AMF.

14. A communications apparatus, comprising:

a transceiving unit, configured to send a first request message to a first network device, where the first request message requests to access a target network slice, and the first request message includes identification information of a network slice group to which the target network slice belongs and first identification information of the target network slice;

the transceiver unit is further configured to receive a response message from the first network device, where the response message indicates that the second network device allows the communication apparatus to access the target network slice.

15. The apparatus according to claim 14, wherein the identification information of the network slice group to which the target network slice belongs is carried in the first identification information of the target network slice.

16. The apparatus according to claim 14 or 15, wherein the identification information of the second network device is carried in the identification information of the network slice group to which the target network slice belongs.

17. The apparatus according to claim 16, wherein the identification information of the second network device comprises at least one of an identification of an area corresponding to the second network device, an identification of a set of network devices to which the second network device belongs, and a pointer corresponding to the second network device.

18. The communications apparatus according to any one of claims 14 to 17, wherein the first identification information of the target network slice is generated by modifying an S-NSSAI of the target network slice.

19. The communication apparatus according to any one of claims 14 to 18, wherein the second network device is an AMF.

20. A communications apparatus, comprising:

a receiving and sending unit, configured to receive a first request message from a terminal device, where the first request message requests to access a target network slice, and the first request message includes identification information of a network slice group to which the target network slice belongs and first identification information of the target network slice;

a processing unit, configured to send a second request message to a second network device in response to the first request message;

the transceiver unit is further configured to receive a response message from the second network device, where the response message indicates that the second network device allows the terminal device to access the target network slice;

the transceiver unit is further configured to send the response message to the terminal device.

21. The communications apparatus of claim 20, wherein the transceiver unit is further configured to: acquiring association information, wherein the association information comprises a corresponding relation between identification information of a network slice group to which the target network slice belongs and the second network equipment, and/or the association information comprises a corresponding relation between the first identification information and the second network equipment;

the processing unit is specifically configured to: and sending a second request message to the second network equipment according to at least one item of the identification information of the network slice group to which the target network slice belongs, the first identification information and the association information.

22. The communications apparatus according to claim 20 or 21, wherein identification information of the second network device is carried in identification information of a network slice group to which the target network slice belongs, and the processing unit is specifically configured to: and sending the second request message to the second network equipment according to the identification information of the second network equipment.

23. The apparatus according to claim 22, wherein the identification information of the second network device comprises at least one of an identification of an area corresponding to the second network device, an identification of a set of network devices to which the second network device belongs, and a pointer corresponding to the second network device.

24. A communication apparatus according to any of claims 20 to 23, wherein identification information of a network slice group to which the target network slice belongs is carried in the first identification information.

25. The communications apparatus of any of claims 20 to 24, wherein the first identification information of the target network slice is generated after S-NSSAI modification of the target network slice.

26. The communications apparatus according to any one of claims 20 to 25, wherein the second network device is an AMF.

27. A communication device comprising a processor and interface circuitry configured to receive signals from a communication device other than the communication device and transmit the signals to or from the processor to the communication device other than the communication device, the processor being configured to implement the method of any one of claims 1 to 6 by logic circuitry or executing code instructions.

28. A communications device comprising a processor and interface circuitry for receiving and transmitting signals from or sending signals to a communications device other than the communications device, the processor being operable by logic circuitry or executing code instructions to implement the method of any of claims 7 to 13.

29. A computer readable storage medium storing computer instructions which, when run on a communication device, cause the communication device to perform the method of any one of claims 1 to 6.

30. A computer readable storage medium storing computer instructions which, when run on a communication device, cause the communication device to perform the method of any one of claims 7 to 13.