CN115244980B

CN115244980B - Session release method and device

Info

Publication number: CN115244980B
Application number: CN202080098378.3A
Authority: CN
Inventors: 杨皓睿; 付喆
Original assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Current assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Filing date: 2020-04-07
Publication date: 2024-07-09
Anticipated expiration: 2040-04-07

Abstract

The embodiment of the application discloses a session release method and a session release device, and relates to the technical field of communication. The method comprises the following steps: the terminal receives first information from access network equipment; the terminal determines that the access network equipment does not support the first network slice according to the first information; the terminal releases the first session established on the first network slice. Therefore, the embodiment of the application receives the signaling from the access network equipment through the terminal to determine the network slice which is not supported by the access network equipment, is beneficial to realizing the rapid release of the session established on the network slice, reduces the signaling interaction in the session release process, saves the signaling overhead and avoids the waste of network resources.

Description

Session release method and device

Technical Field

The present application relates to the field of communications technologies, and in particular, to a session release method and apparatus.

Background

In the Release15 standard protocol of the third generation partnership project (3rd Generation Partnership Project,3GPP), the protocol content considers the scenario that all access network devices within the same tracking area list (TRACKING AREA LIST, TAL) under one access and mobility management function (ACCESS AND mobility management function, AMF) network element support the same network slice. In this scenario, when the terminal moves to a new TAL, if the new AMF does not support a certain network slice, the old AMF network element is triggered by the new AMF network element to release the session established on the network slice.

At present, release17 standard protocol needs to study the scenario that may support different network slices between different access network devices within the same TAL under one AMF network element. In this scenario, however, there may be a case where only the access network device is replaced, and the AMF network element is not replaced. Since the AMF network element cannot know which network slice the session established on needs to be released, how to release the session established on the network slice that is not supported by the access network device needs further investigation.

Disclosure of Invention

The embodiment of the application provides a session release method and a session release device, which are used for realizing the purpose of quickly releasing a session established on a network slice which is not supported by access network equipment, reducing signaling interaction in the session release process and saving signaling overhead.

In a first aspect, an embodiment of the present application provides a session release method, including:

the terminal receives first information from access network equipment; the terminal determines that the access network equipment does not support a first network slice according to the first information; the terminal releases a first session established on the first network slice.

In the embodiment of the application, the terminal receives the signaling from the access network equipment to determine the network slice which is not supported by the access network equipment, thereby being beneficial to realizing the rapid release of the session established on the network slice, reducing the signaling interaction in the session release process and saving the signaling cost.

In a second aspect, an embodiment of the present application provides a session release method, including:

The access network device sends second information to an access and mobility management function AMF network element, wherein the second information comprises fourth indication information and fifth indication information, the fourth indication information is used for indicating that the access network device does not support a first network slice, and the fifth indication information is used for indicating that a protocol data unit session identifier of a first session established on the first network slice is released.

It can be seen that, in the embodiment of the present application, signaling is sent to the AMF network element by the access network device to notify that the network slice does not support the session identifier established on the network slice, so that the session established on the network slice that is not supported by the access network device is released quickly, signaling interaction in the session release process is reduced, and signaling overhead is saved.

In a third aspect, an embodiment of the present application provides a session release method, including:

The access and mobility management function, AMF, network element receives second information from access network equipment, wherein the second information comprises fourth indication information and fifth indication information, the fourth indication information is used for indicating that the access network equipment does not support a first network slice, and the fifth indication information is used for indicating that protocol data unit session identification of a first session established on the first network slice is released.

It can be seen that, in the embodiment of the present application, the AMF network element receives the signaling from the access network device to obtain the network slice unsupported and the session identifier established on the network slice, which is favorable for implementing quick release of the session established on the network slice unsupported by the access network device, reducing signaling interaction in the session release process, and saving signaling overhead.

In a fourth aspect, an embodiment of the present application provides a session release method, including:

The session management function SMF network element receives sixth indication information and seventh indication information from the access and mobility management function AMF network element, where the sixth indication information is used to indicate that the access network device does not support the first network slice, and the seventh indication information is used to indicate to release a protocol data unit session identifier of the first session established on the first network slice.

In the embodiment of the application, the SMF network element receives the indication information from the AMF network element to acquire the unsupported network slice and the session identifier established on the network slice, thereby being beneficial to realizing quick release of the session established on the network slice which is not supported by the access network equipment, reducing signaling interaction in the session release process and saving signaling overhead.

In a fifth aspect, an embodiment of the present application provides a session release device, which is applied to a terminal, where the device includes a processing unit and a communication unit, where the processing unit is configured to: receiving, by the communication unit, first information from an access network device; determining that the access network equipment does not support a first network slice according to the first information; releasing the first session established on the first network slice.

In a sixth aspect, an embodiment of the present application provides a session release apparatus, which is applied to an access network device, where the apparatus includes a processing unit and a communication unit, where the processing unit is configured to: and sending second information to an access and mobility management function AMF network element through the communication unit, wherein the second information comprises fourth indication information and fifth indication information, the fourth indication information is used for indicating that the access network equipment does not support the first network slice, and the fifth indication information is used for indicating that the protocol data unit session identification of the first session established on the first network slice is released.

In a seventh aspect, an embodiment of the present application provides a session release device, which is applied to an AMF network element, where the device includes a processing unit and a communication unit, where the processing unit is configured to: receiving, by the communication unit, second information from an access network device, where the second information includes fourth indication information and fifth indication information, where the fourth indication information is used to indicate that the access network device does not support the first network slice, and the fifth indication information is used to indicate a protocol data unit session identifier that releases the first session established on the first network slice.

In an eighth aspect, an embodiment of the present application provides a session release device, which is applied to a session management function SMF network element, where the device includes a processing unit and a communication unit, where the processing unit is configured to: and receiving sixth indication information and seventh indication information from an access and mobility management function (AMF) network element through the communication unit, wherein the sixth indication information is used for indicating that the access network equipment does not support the first network slice, and the seventh indication information is used for indicating to release a Protocol Data Unit (PDU) session identifier of a first session established on the first network slice.

In a ninth aspect, an embodiment of the present application provides a terminal, including a processor, a memory, a communication interface, and one or more programs, where the one or more programs are stored in the memory and configured to be executed by the processor, the programs including instructions for performing the steps in any of the methods of the first aspect of the embodiments of the present application.

In a tenth aspect, embodiments of the present application provide an access network device comprising a processor, a memory, a communication interface, and one or more programs, wherein the one or more programs are stored in the memory and configured for execution by the processor, the programs comprising instructions for performing the steps of any of the methods of the second aspect of embodiments of the present application.

In an eleventh aspect, an embodiment of the present application provides an AMF network element comprising a processor, a memory, a communication interface and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the processor, the programs comprising instructions for performing the steps in any of the methods of the third aspect of the embodiments of the present application.

In a twelfth aspect, an embodiment of the present application provides a session management function SMF network element, comprising a processor, a memory, a communication interface, and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the processor, the programs comprising instructions for performing the steps in any of the methods of the fourth aspect of the embodiments of the present application.

In a thirteenth aspect, an embodiment of the present application provides a chip, including: a processor for calling and running a computer program from a memory, causing a device on which the chip is mounted to perform some or all of the steps as described in any of the methods of the first, second, third and fourth aspects of embodiments of the application.

In a fourteenth aspect, embodiments of the present application provide a computer-readable storage medium storing a computer program for electronic data exchange, wherein the computer program is operable to cause a computer to perform part or all of the steps described in any of the methods of the first, second, third and fourth aspects of the embodiments of the present application.

In a fifteenth aspect, embodiments of the present application provide a computer program, wherein the computer program is operable to cause a computer to perform some or all of the steps as described in any of the methods of the first, second, third and fourth aspects of the embodiments of the present application. The computer program may be a software installation package.

Drawings

The drawings that accompany the embodiments or the prior art description can be briefly described as follows.

Fig. 1 is a schematic diagram of a communication system according to an embodiment of the present application;

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

Fig. 3 is a schematic architecture diagram of a communication scenario provided in an embodiment of the present application;

fig. 4 is a flow chart of a session release method according to an embodiment of the present application;

fig. 5 is a schematic flow chart of a session release method according to an embodiment of the present application;

fig. 6 is a schematic flow chart of a method for releasing session according to an embodiment of the present application;

fig. 7 is a flowchart of another session release method according to an embodiment of the present application;

fig. 8 is a flow chart of a method for releasing a session according to an embodiment of the present application;

fig. 9 is a functional unit composition block diagram of a session release device according to an embodiment of the present application;

FIG. 10 is a block diagram showing the functional units of a fork-type session release device according to an embodiment of the present application;

FIG. 11 is a functional block diagram of a cross-talk release device according to an embodiment of the present application;

Fig. 12 is a functional unit block diagram of a session release device according to still another embodiment of the present application;

fig. 13 is a schematic structural diagram of a terminal according to an embodiment of the present application;

Fig. 14 is a schematic structural diagram of an access network device according to an embodiment of the present application;

Fig. 15 is a schematic structural diagram of an access and mobility management function network element according to an embodiment of the present application;

fig. 16 is a schematic structural diagram of a session management function network element according to an embodiment of the present application.

Detailed Description

The technical scheme in the embodiment of the application will be described below with reference to the accompanying drawings.

The technical solution of the embodiment of the present application may be applied to a wireless communication system, where the wireless communication system may include a non-terrestrial communication network (non-TERRESTRIAL NETWORK, NTN) system, a long term evolution (long term evolution, LTE) system, an LTE frequency division duplex (frequency division duplex, FDD) system, an LTE time division duplex (time division duplex, TDD), a fifth generation (5th generation,5G) new air interface (NR) communication system, or a future evolution communication system. Taking the example that the wireless communication system is a 5G NR communication system, please refer to fig. 1.

In fig. 1, the example communication system 100 includes a terminal 110, an access network device 120, an access and mobility management function (ACCESS AND mobility management function, AMF) network element 130, a session management function (session management function, SMF) network element 140, a user plane function (user plane function, UPF) network element 150, a network slice selection function (network slice selectionfunction, NSSF) network element 160. The AMF network element 130, the SMF network element 140, the UPF network element 150, NSSF and the network element 160 belong to a core network element (or referred to as a network function network element), and it should be noted that other network elements in the core network element are also included in the embodiment of the present application, and are not limited specifically. In addition, the connection between the network elements may be a wireless connection or a wired connection, so that, for convenience and intuitionistic representation of the connection relationship between the network elements, fig. 1 is shown by solid lines, and the interfaces between the network elements are described in detail in the prior art, which is not described in detail in the embodiments of the present application.

Specifically, the terminal 110 in the embodiment of the present application may include a User Equipment (UE), a user terminal, a handheld terminal, a notebook computer, a subscriber unit (subscriber unit), a cellular phone (cellular phone), a smart phone (smart phone), a wireless data card, a Personal Digital Assistant (PDA) computer, and may also include a vehicle-mounted device, a vehicle-mounted terminal, a vehicle device, or an automobile device. Terminal 110 may also be a cellular telephone, a cordless telephone, a session initiation protocol (session initiation protocol, SIP) phone, a wireless local loop (wireless local loop, WLL) station, a Personal Digital Assistant (PDA), a handheld device with wireless communication capabilities, a computing device or other processing device connected to a wireless modem, a relay device, a wearable device, a terminal device in a 5G NR system, or a terminal device in a future evolved public land mobile network (public land mobile network, PLMN). The embodiment of the present application is not particularly limited thereto.

In an embodiment of the present application, terminal 110 includes a hardware layer, an operating system layer running above the hardware layer, and an application layer running above the operating system layer. The hardware layer includes hardware such as a central processing unit (central processing unit, CPU), a memory management unit (memory management unit, MMU), and a memory (also referred to as a main memory). The operating system may be any one or more computer operating systems that implement business processes through processes (processes), such as a Linux operating system, a Unix operating system, an Android operating system, an iOS operating system, or a Windows operating system. The application layer comprises applications such as a browser, an address book, word processing software, instant messaging software and the like. In addition, the embodiment of the present application is not particularly limited to the specific structure of the execution body of the method provided in the embodiment of the present application, as long as the communication can be performed in the method provided in accordance with the embodiment of the present application by executing the program recorded with the code of the method provided in the embodiment of the present application, and for example, the execution body of the method provided in the embodiment of the present application may be the terminal 110 or a functional module capable of calling the program and executing the program in the terminal 110.

Specifically, the access network device 120 may be regarded as a radio access network (radio access network, RAN) device or AN Access Network (AN) device, which is mainly responsible for functions such as radio resource management, quality of service (quality of service, qoS) management, data compression, and encryption on the air interface side. Access network device 120 may include various forms of base stations such as: macro base station, micro base station, relay station, access Point (AP), etc. In communication systems employing different radio access technologies, the names of base station enabled devices may vary. For example, in the fifth generation (5th generation,5G) communication system, referred to as next generation node B (next generation node B, gNB) or next generation evolved node B (next generation evolved node B, ng-eNB); in the LTE system, referred to as evolved NodeB (eNB or eNodeB) or; in the third generation (3rd generation,3G) system, it is called Node B (Node B) or the like.

Specifically, the AMF network elements 130 are distributed in the core network and mainly responsible for signaling processing, and may also provide control plane functions, such as access control, mobility management, attachment and detachment, and gateway selection. Furthermore, in case the AMF network element 130 provides services for a session in the terminal 110, the AMF network element may provide a storage resource of a control plane for the session to store a session identity, a session management function (session management function, SMF) network element identity associated with the session identity, etc.

In particular, the SMF network element 140 may be configured to be responsible for user plane network element selection, user plane network element redirection, IP address assignment, bearer establishment, modification and release, and QoS control.

In particular, the UPF network element 150 may be configured to be responsible for forwarding and receiving user data in the terminal 110. For example, UPF network element 150 receives user data from the data network and transmits the user data to terminal 110 via access network device 120; or UPF network element 150 receives user data from terminal 110 via access network device 120 and forwards the user data to the data network. In addition, the SMF network element 140 manages and controls transmission resources and scheduling functions in the UPF network element 150 that provide services to the terminal 110.

Specifically, NSSF network element 160 may be used to select a network slice for terminal 110, determine network slice selection assistance information (network slice selection assistance information, NSSAI), determine AMF network element 130 serving terminal 110, and the like.

Before describing the session release method provided by the embodiment of the present application in detail, the communication technology related to the embodiment of the present application is described.

Network slice (network slice):

Network slicing is a combination of network functions and resources required to perform a certain service or services, and is a complete logical network. The network slice can flexibly allocate and reallocate resources according to the demands of users, and can be understood as meeting various software-defined functions through the same set of hardware. Furthermore, network slices are defined in one PLMN, which may comprise network function network elements of the core network control plane and the user plane.

The concept of network slice selection assistance information (network slice selection assistance information, NSSAI) is introduced in the network slice. Wherein NSSAI may include one or more single network slice selection assistance information (single network slice selection assistance information, S-NSSAI), and the network slice may be identified by S-NSSAI. It will be appreciated that to identify end-to-end network slices, each network slice is uniquely identified by an S-NSSAI. In the present application, a network slice identification (indentify, ID) represents S-NSSAI for identifying the network slice. In addition, one S-NSSAI consists of Slice/service type (Slice/SERIVE TYPE, SST) and Slice difference (Slice Differentiator, SD). The SST is used for identifying the slice type, and is the necessary information in S-NSSAI, the length is 8bits, and the value range is 0-255. The standardized SST values provide a way to establish global interoperability of the slices so that PLMNs can more efficiently support roaming for the most common slice/service types. Standardized SST values may indicate enhanced mobile broadband services (enhanced mobile broadhand, eMBB), ultra-reliable low-latency communications (ultra-reliable low latency communications, URLLC), mass machine class communications (MASSIVE MACHINE TYPE communications, mMTC), and vehicle-mounted communications (vehicle to everything, V2X). SD can be used as a supplement to SST to distinguish multiple network slices under the same SST, which is optional information in S-NSSAI and is 24bits in length.

Network slice instance (network SLICE INSTANCE):

One network slice instance may be associated with one or more S-NSSAI or one S-NSSAI may be associated with one or more network slice instances based on the operator' S operational or deployment requirements. In one PLMN, when one S-NSSAI is associated with multiple network slice instances, one of the multiple network slice instances serves a terminal that allows use of this S-NSSAI, and the multiple network slice instances may be deployed in the same or different tracking areas (TRACKING AREAS, TA). In case the multiple network slice instances are deployed in the same TA, the AMF network element serving the terminal may logically belong to the multiple network slice instances associated with the S-NSSAI, that is, the multiple network slice instances may comprise the same AMF network element. Further, for any one of S-NSSAI, the network may use only one network slice instance to serve the terminal associated with that S-NSSAI at any time unless the network slice instance is no longer valid in the given registration area or the permitted NSSAI (allowed NSSAI) stored by the terminal changes, etc. When an S-NSSAI is associated with multiple network slice instances, the multiple network slice instances may be referred to as network slice instances contained by the S-NSSAI labeled network slice, that is, the multiple network slice instances belong to the network slice. An identifier (NSI ID) of a network slice instance may be used to identify a network slice instance.

Each network slice instance may include a set of network function network elements, while different network slice instances typically include different sets of network function network elements. The set of network function elements may include the AMF element 130, the SMF element 140, the UPF element 150, and the like in fig. 1, and the different sets of network function elements may also include the same network function element. For example, different network slice instances may correspond to the same AMF network element or SMF network element. Furthermore, each network slice may include a set of network function network elements that may be considered as a set of network function network elements that are included by all network slice instances belonging to the network slice. When a network slice instance or network slice comprises a network function network element, the network function network element may be considered to support the network slice instance or network slice. For example, if a network slice instance includes an AMF network element, the AMF network element may be considered to support the network slice instance. When the network deployment is performed, the network slice or the network slice instance supported by each network function network element can be deployed in advance. Or during operation of the communication network, the network slice or network slice instance supported by one or some network function network element may be updated, which is not particularly limited by the embodiments of the present application.

In the embodiment of the present application, terminal 110 may access multiple network slices, or may access the same network slice based on one or more network slice instances. Terminal 110 may establish one or more protocol data unit (protocl data unit, PDU) sessions in one network slice instance, that is, each PDU session is established on a network slice instance basis. In addition, the network slice instance on which a PDU session is established is referred to as the network slice instance on which the PDU session is established, or as the network slice instance to which the PDU session relates. Meanwhile, the network slice to which the network slice instance belongs is referred to as the network slice on which the PDU session is established, or as the PDU session-related network slice. Wherein the PDU session is a connection between the terminal 110 and a data network (DU) for providing a PDU connection service, and a connection type between the terminal 110 and the DU may be a network protocol (internet protocol, IP) connection, an ethernet connection, an unstructured data connection, or the like. For PDU connectivity services supported by the 5G core network, it is generally referred to as a service providing PDU exchanges between the terminal 110 and the DN as determined by the data network name (data network name, DNN). In the present application, terminal 110 may establish one or more PDU sessions to connect to the same DN or to different DNs, while terminal 110 may establish PDU sessions serviced by different UPF network elements 150 to connect to the same DN.

In summary, a big feature of the 5G network architecture is network slicing, i.e. dividing the core network into a plurality of network slices to provide customized services. The following embodiment of the present application provides a network architecture schematic diagram based on network slicing, please refer to fig. 2. First, the AMF network element 130 connects the access network device 120, and communication is established between the access network device 120 and the terminal 110. Second, network slice 1 is identified by an S-NSSAI, which S-NSSAI is associated with network slice instance 11, network slice instance 12, network slice instance 13; network slice 2 is identified by an S-NSSAI, which S-NSSAI is associated with network slice instance 21. Since network slice instance 11, network slice instance 12, network slice instance 13, and network slice instance 21 are deployed in the same TA, each of the above network slice instances includes the same AMF network element 130, while each network slice instance includes different SMF network elements, UPF network elements. Then, a PDU session 1 is established on the network slice example 11, a PDU session 2 is established on the network slice example 12, and a PDU session 3 is established on the network slice example 13, that is, a PDU session 1, a PDU session 2, and a PDU session 3 are established on the network slice 1; a PDU session 4 is established on the network slice instance 21, that is, a PDU session 4 is established on the network slice 2. It should be noted that, fig. 2 illustrates an AMF network element, an SMF network element, and a UPF network element included in each network slice example, and of course, other core network elements may also be included. In addition, one PDU session may be established on each network slice in fig. 2, or a plurality of PDU sessions may be established, without being limited thereto.

Before describing the session release method provided by the embodiment of the present application in detail, the communication scenario related to the embodiment of the present application is described.

The communication scene related to the embodiment of the application can be a scene of changing the access network equipment or a scene of not changing the access network equipment. In the case where the access network device is replaced, a registration procedure, a service request procedure, a configuration update or a handover procedure may be performed, and in the case where the access network device is not replaced, a registration procedure, a service request procedure, a configuration update, etc. may be performed. In addition, the communication scene related to the embodiment of the application can be a scene of changing an AMF network element or a scene of not changing the AMF network element. In the scene of changing the AMF network element and the scene of not changing the AMF network element, a registration process, a service request process, a configuration update process, a switching process, a session release process, and the like may be executed. Specifically, in the embodiment of the present application, in a scenario where the access network device is replaced and the AMF network element is not replaced, the access network device may not support network slicing, and please refer to fig. 3.

In fig. 3, terminal 310 is terminal 110 described in fig. 1, access network device 320 is access network device 120 described in fig. 1, and core network 330 includes AMF network element 130, SMF network element 140, UPF network element 150, NSSF network element 160, and the like described in fig. 1. Wherein the access network device 320 comprises a source access network device 320A and a target access network device 320B and is connected to the same AFM network element, i.e. only the access network device is replaced but not the AMF network element. In addition, source access network device 320A supports network slices 1 and 2 and target access network device 320B supports network slices 2 and 3. As the terminal 310 moves from the source access network device 320A to the target access network device 320B, the target access network device 320B is caused to not support network slice 1 provided by the source access network device 320A. At this point, the AFM network element may not know that the target access network device 320B does not support network slice 1 and that the PDU session established on network slice 1 needs to be released.

In order to reduce the location update signaling caused by the change of the location of the terminal, a method of registering a plurality of tracking areas (TRACKING AREA, TA) is adopted, and a tracking area list (TRACKING AREA LIST, TAL) is formed by a plurality of TAs. When a terminal accesses the network through registration, the AMF network element will assign the TAL to the terminal, and the terminal need not perform TA update when moving in the area within the TAL. For the access network device, each cell only belongs to one TA, and the broadcast message only needs to broadcast the information of one TA.

Since it is assumed in the Release15 standard protocol of 3GPP that all access network devices in the same TAL under one AMF network element support the same network slice, when the terminal moves to a new TAL, if the new AMF does not support a certain network slice, the old AMF network element is triggered by the new AMF network element to Release the session established on the network slice.

In view of the above-mentioned problems, the following describes the execution steps of the session release method from the viewpoint of a method example, referring to fig. 4. Fig. 4 is a flow chart of a session release method according to an embodiment of the present application, where the method includes:

S410, the access network equipment sends first information to the terminal.

Specifically, the first information may be a newly added signaling in the 5G communication standard, where the newly added signaling may be used to indicate each network slice identifier (indentify, ID) supported by the access network device, and each network slice identifier may be S-NSSAI of each network slice. In addition, the first information may be a message or information specified in the prior art, for example, system information, RRC message, paging message, RRC connection reconfiguration message, handover command, non-access stratum (NAS) message, access Network (AN) message, etc., and the indication information for indicating each network slice identifier supported by the access network device may be carried in the message or information specified in the prior art.

It should be noted that, the access network device in the embodiment of the present application may be determined according to different system flows and communication scenarios. For example, when the terminal moves to a new cell, if the embodiment of the present application is applied to a registration procedure or a service request procedure, the access network device may be an access network device corresponding to the new cell; if the embodiment of the application is applied to a session release flow, a switching flow or a configuration updating flow, the access network device can be the access network device corresponding to the old cell or the access network device corresponding to the new cell.

Specifically, the first information may be determined by a current connection management state of the terminal. The connection management may include, among other things, setting up and releasing a signaling connection of the N1 interface between the terminal and the AMF, that is, the connection management may be used for setting up and releasing signaling between the terminal and the AMF network element. Whereas the signaling connection may comprise AN message connection between the terminal and the access network device, AN N2 message connection between the access network device and the AMF, i.e. the signaling connection may be used for NAS message interaction between the terminal and the AMF network element.

Further, the current connection management state of the terminal may include an IDLE state (CM-IDLE) and a CONNECTED state (CM-CONNECTED). When the terminal is in an idle state, the terminal does not establish NAS message connection with the AMF through the N1 interface. At this time, the terminal may perform cell selection, cell reselection, and PLMN selection. When a terminal in an idle state needs to transmit a NAS message, the terminal may establish a NAS message connection to the AMF by initiating a service request or registration procedure. And when the AN message connection is established between the terminal and the access network equipment, the terminal can be switched into a connection state from AN idle state. Meanwhile, the transmission of the initial NAS message (registration request, service request or deregistration request) may also trigger the terminal to change from the idle state to the connected state.

It can be seen that the terminals in different connection management states can establish different system flows when receiving or transmitting signaling. Accordingly, the first information may be determined by the current connection management state of the terminal. For example, when the terminal enters a new cell, if the terminal is currently in an idle state, the terminal may receive system information broadcast from an access network device corresponding to the new cell; if the terminal is currently in a connected state, the terminal may receive an RRC message, an RRC connection reconfiguration message, or a handover command from an access network device corresponding to the old cell, and so on.

And S420, after receiving the first information, the terminal determines that the access network equipment does not support the first network slice according to the first information.

Wherein the access network device does not support the first network slice may be understood as that the access network device does not currently deploy the first network slice or the first network slice Identification (ID). The first network slice may include one network slice or a plurality of network slices, and the first network slice identification may be one or more S-NSSAI of the first network slice.

This also affects how the terminal determines the network slices supported by the access network device, since the terminal is currently in different connection management states, which will result in different received signaling. The following will describe the case where the terminal is in an idle state and a connected state, respectively.

In one possible example, in a case that a current connection management state of the terminal is an idle state, the first information includes first indication information, where the first indication information is used to indicate network slice identifiers supported by the access network device; the terminal determining, according to the first information, that the access network device does not support the first network slice may include: the terminal determines that the access network equipment does not support the first network slice according to the first indication information and the first allowed network slice identifier, or determines that the access network equipment does not support the first network slice according to the first indication information and the network slice identifier of the PDU session currently established.

Further, the first indication information is carried in the system information.

Wherein the first allowed network slice identity is notified by the AMF network element during registration of the terminal to the network, and the first allowed network slice identity may be allowed NSSAI or may be one or more S-NSSAI of the network slices. That is, the first allowed network slice identity may be used to indicate one or more network slices that the terminal is allowed to access, and the terminal may be served by the network slice to which the first allowed network slice identity corresponds, such as by establishing one or more PDU sessions on the network slice.

It should be noted that, in the case that the terminal is in an idle state, the terminal receives the system information broadcast by the access network device, and obtains, through the first indication information carried in the system information, each network slice identifier supported by the access network device. In an embodiment of the present application, the network slice identifier may be S-NSSAI of the network slice. Second, the RRC layer of the terminal transmits the each network slice identity to the NAS layer of the terminal. The NAS layer of the terminal then compares this each network slice identity with the first allowed network slice identity currently stored by the terminal. If the first network slice identity is within the first allowed network slice identity and not within each network slice identity, the terminal knows that the access network device does not support the first network slice. Or the NAS layer of the terminal compares the each network slice identity with the network slice identity of the PDU session currently established by the terminal. If the first network slice identity is within the network slice identity of the currently established PDU session and not within each of the network slice identities, the terminal knows that the access network device does not support the first network slice.

In the embodiment of the present application, one or more PDU sessions may be established or not established on the first network slice, so after the NAS layer of the terminal confirms that the access network device does not support the first network slice, the NAS layer of the terminal may further determine whether the first session is established on the first network slice. Wherein the first session may comprise one or more PUD sessions.

If the first session is not established on the first network slice, it indicates that the access network device and the core network element do not establish the context and related resources of the first session, for example, the first session in the AMF network element does not occupy the control plane resources, the first session in the SMF network element does not occupy the control plane resources, and the first session in the UPF network element does not occupy the user plane transmission resources, which does not cause the waste of the resources. Thus, the terminal does not need to enter the connected state from the idle state, but simply marks that the access network device does not support the first network slice, and does not need to establish a PDU session on the first network slice in a subsequent process. In addition, since the terminal may move to a new cell before entering the connection state next time, and the network slice that may be supported by the access network device corresponding to the new cell may also change, the terminal does not need to return to the connection state. Only when the terminal has uplink data or signaling to be sent, the terminal enters the connection state again, and after entering the connection state, the AMF network element informs the new second allowable network slice identification.

If a first session is established on the first network slice, this will result in failure of transmission or reception of traffic data on the communication connection established by the first session, since the terminal may still establish a connection with the DN through the first session, but the access network device does not support the first session. Furthermore, since the core network element may still establish the context of the first session and related network resources, e.g. control plane resources occupied by the first session in the AMF network element. It can be seen that the session established on the network slice which is not supported by the access network device is not released, which not only results in failure of service data transmission, but also results in waste of network resources.

For the case that the first session is established on the first network slice, the terminal may change from the idle state to the connected state and then release the first session. Therefore, the terminal can establish AN AN signaling connection between the terminal and the access network equipment through a registration process or a service request process, so that the terminal enters a connection state, and then the core network element executes session release. The following will specifically describe.

For the process that the terminal enters the connection state through the registration flow, as shown in fig. 5, the terminal currently in the idle state needs to release the first session is implemented by interaction of the access network device, the AMF network element and the SMF network element. Firstly, a terminal sends a first RRC message to an access network device, where the first RRC message may carry a registration request, where the first registration request may carry indication information indicating that the access network device does not support a first network slice, may carry a network slice identifier of the first network slice, may also carry a PDU session identifier of the first session, or may carry a bitmap (bitmap) indicating the PDU session. It should be noted that the registration request may carry a PDU session state (status) parameter, which may be used for synchronizing the existing PDU session between the terminal and the AMF network element, and may be in the form of a bitmap, such as bits 1-8, where each bit may correspond to a PDU session. If the PDU session exists, the corresponding bit of the PDU session is taken as 1, otherwise, the PDU session is taken as 0. Then, the access network device receives the first RRC message, and sends a first N2 message to the AMF network element, where the first N2 message may carry the first registration request. Secondly, after receiving the first N2 message, the AMF network element triggers a session release request, and sends a first session release request to the SMF network element, where the first session release request is used to request to release the first session. Again, the SMF network element receives the first session release request, performs a PDU session release procedure to release the context and related resources of the first session on the terminal and the AMF network element, and sends a first session release response to the AMF network element. Then, the AMF network element receives the first session release response, releases the control plane resource of the first session, and sends a first NAS message to the terminal, where the first NAS message may be a registration grant (registration accept), and the registration grant may carry a new allowed network slice identifier, or may carry indication information indicating that the terminal releases the first session, for example, using bitmap indicating a PDU session. Finally, the terminal receives registration agreement, obtains a new allowed network slice identifier, and releases the context of the first session.

For the process that the terminal enters the connection state through the service request flow, as shown in fig. 6, the terminal currently in the idle state needs to release the first session is implemented by interaction of the access network device, the AMF network element and the SMF network element. Firstly, a terminal sends a second RRC message to an access network device, wherein the second RRC message can carry a first service request, and the first service request can carry indication information for indicating that the access network device does not support a first network slice, can carry a network slice identifier of the first network slice, and can also carry a PDU session identifier of the first session or a bitmap for indicating the PDU session. It should be noted that the service request may carry a PDU session state parameter, where the parameter may be used for synchronizing an existing PDU session between the terminal and the AMF network element, and the parameter may be in a bitmap form, for example, bits 1-8, and each bit may correspond to one PDU session. If the PDU session exists, the corresponding bit of the PDU session is taken as 1, otherwise, the PDU session is taken as 0. Then, the access network device receives the second RRC message, and sends a second N2 message to the AMF network element, where the second N2 message may carry the first service request. And secondly, after the AMF network element receives the second N2 message, triggering a session release request, and sending a second session release request to the SMF network element, wherein the second session release request is used for requesting to release the first session. And the SMF network element receives the second session release request, executes a PDU session release procedure to release the context and related resources of the first session on the terminal and the AMF network element, and sends a second session release response to the AMF network element. Then, the AMF network element receives a second session release response, releases the control plane resource of the first session, and sends a second NAS message to the terminal, where the second NAS message may be a service accept message, and the service accept message may carry indication information indicating whether the terminal releases the first session. And then, the AMF network element sends a third NAS message to the terminal, wherein the third NAS message can be a configuration updating command, and the configuration updating command can carry indication information for indicating the new allowed network slice identifier and also can carry indication information for indicating the terminal to release the first session. And finally, the terminal receives a configuration update command, obtains a new allowed network slice identifier, and releases the context of the first session.

In summary, in the case where the terminal is currently in the idle state, the flow chart of the session release method shown in fig. 4 may also be shown in fig. 7. The fourth information may be the first RRC message or the second RRC message described above. In the case that the fourth information is the first RRC message, the fifth information may be the first NAS message, the third session release request may be the first session release request, the third session release response may be the first session release response, and the sixth information may be the first NAS message; in the case where the fourth information is the second RRC message, the fifth information may be the second N2 message, the third session release request may be the second session release request, the third session release response may be the second session release response, the sixth information may be the second NAS message, and the seventh message may be the third NAS message. The specific process is described above and will not be described here again. The following describes the case where the terminal is currently in a connected state.

In one possible example, in a case where the current connection management state of the terminal is a connection state, the first information may include second indication information and/or third indication information, the second indication information may be used to indicate that the access network device does not support the first network slice, the access network device may be a target access network device, and the third indication information may be used to indicate that the PDU session identifier of the first session is released.

In particular, the second indication information may be a cause (cause) value, and by the cause value it is indicated that the access network device does not support the first network slice, which may be the target access network device.

Further, the second indication information and/or the third indication information are carried in an RRC message.

Further, the RRC message may be a handover command or an RRC connection reconfiguration message. It can be appreciated that after the terminal moves from the source access network device to the target access network device, a handover procedure is required. At this time, the terminal receives a handover command or an RRC connection reconfiguration message sent by the source access network device.

It should be noted that, when the terminal is in a connection state, the RRC layer of the terminal receives the RRC message from the access network device, and obtains, through the second indication information and/or the third indication information carried in the RRC message, a network slice that is not supported by the access network device, and a PDU session identifier that needs to be released, that is, a PDU session identifier of the first session. Then, the RRC layer of the terminal transmits the second indication information and/or the third indication information to the NAS layer, and the NAS layer deletes the context of the first session.

S430, the terminal releases the first session established on the first network slice.

It can be seen that in the embodiment of the present application, signaling is sent to a terminal through an access network device, and the terminal determines, according to the information, a network slice that is not supported by the access network device, so that it is beneficial to implementing fast release of a session established on the network slice, reducing signaling interaction in the session release process, and saving signaling overhead.

As in the above example, the embodiment of the present application provides a flow chart of a session release method, please refer to fig. 8.

And S810, the access network equipment sends second information to the AMF network element.

The second information may include fourth indication information and fifth indication information, where the fourth indication information may be used to indicate that the access network device does not support the first network slice, and the fifth indication information may be used to indicate a PDU session identifier that releases the first session established on the first network slice.

In particular, the fourth indication information may be a cause (cause) value, and the cause value indicates that the access network device does not support the first network slice.

It should be noted that, the second information may be a newly added signaling in the 5G communication standard, and the newly added signaling may include fourth indication information and fifth indication information. The first information may also be a prior art specified message, such as an N2 message, a session release request, etc., and the fourth indication information and the fifth indication information are carried in the prior art specified message.

Specifically, the access network device in the embodiment of the present application may include a source access network device and a target access network device. It will be appreciated that when a terminal moves from a source access network device to a target access network device, a handover procedure needs to be performed. This also results in a different execution body for triggering session release to the AMF network element, due to the different access network devices. The following is a detailed description.

For the case that the source access network device may send the second information to the AMF network element, it may be understood that, in the case that the source access network device learns that the target access network device does not support the first network slice, the source access network device initiates a session release procedure to the AMF network element. At this time, fourth indication information carried in the second information may be used to indicate that the target access network device does not support the first network slice. Wherein, the source access network device knows that the target access network device does not support the first network slice may have the following situations: through the information preconfigured when the network is deployed; through interactive signaling between the source access network device and the target access network device in the switching process, for example, indication information carried in switching request confirmation and the like. It should be noted that, the indication information carried in the interaction signaling between the source access network device and the target access network device may be used to indicate each PDU session identifier of the target access network device, and then, the source access network device may determine the first network slice according to each PDU session identifier of the local end and the indication information. In addition, the source access network device may trigger the session release procedure to the AMF network element during or after the handover procedure, which is not particularly limited in the present application.

For the case that the target access network device may send the second information to the AMF network element, it may be understood that, in the case that the target access network device learns that the first network slice is not supported, the target access network device initiates a session release procedure to the AMF network element. At this time, fourth indication information carried in the second information may be used to indicate that the target access network device does not support the first network slice. Wherein, the target access network device knows that the first network slice is not supported may have the following situations: through the information preconfigured when the network is deployed; through the interactive signaling between the source access network device and the target access network device in the switching process, for example, indication information carried in the switching request and the like. It should be noted that, the indication information carried in the interaction signaling between the source access network device and the target access network device may be used to indicate each PDU session identifier of the source access network device, and then the target access network device may determine the first network slice according to each PDU session identifier of the local end and the indication information. In addition, the target access network device may trigger the session release procedure to the AMF network element during or after the handover procedure, which is not particularly limited in the present application.

Specifically, in the embodiment of the present application, the access network device may further send the first information to the terminal before or after the first information to the AMF network element, which is not limited in particular. In addition, the first information is specifically described as above, and will not be described in detail.

S820, the AMF network element sends sixth indication information and seventh indication information to the SMF network element after receiving the second information.

Wherein the sixth indication information may be used to indicate that the access network device does not support the first network slice, and the seventh indication information may be used to indicate that the PDU session identification of the first session is released.

It should be noted that, the sixth indication information may be fourth indication information carried in the second information, and the seventh indication information may be fifth indication information carried in the second information, that is, the AMF network element may directly forward the information from the access network device to the SMF network element, without reading the information.

S830, after receiving the sixth indication information and the seventh indication information, the SMF network element sends eighth indication information and/or ninth indication information to the AMF network element.

The eighth indication information is used for indicating the AMF network element to release the first session, and the ninth indication information is used for indicating the access network equipment not to support the first network slice.

It should be noted that, whether the SMF network element sends the ninth indication information to the AMF network element may be determined according to whether the AMF network element knows that the access network device does not support the first network slice. If the AMF network element is ensured to know that the access network equipment does not support the first network slice through the pre-configuration during network deployment, the SMF network element can not send ninth indication information to the AMF network element; if there is no pre-configuration or the pre-configuration needs to be updated, the SMF network element may send the ninth indication information to the AMF network element, since the AMF network element may only forward the information from the access network device directly without reading, possibly without knowing that the access network device does not support the first network slice. And under the condition that the AMF network element knows that the access network equipment does not support the first network slice, the AMF network element sends NAS information carrying the new network slice identifier to the terminal.

And S840, after receiving the eighth indication information and/or the ninth indication information, the AMF network element sends third information to the access network equipment.

The third information may include tenth indication information and eleventh indication information, where the tenth indication information may be used to instruct the access network device to release the first session, and the eleventh indication information may be used to indicate the second allowed network slice identifier. It may be understood that after receiving the eighth indication information and/or the ninth indication information, the AMF network element may release the control plane resource of the first session, and send an N2 message to the access network device, or send a NAS message to the terminal, or the like.

S850, the access network equipment receives the third information.

It should be noted that, after the access network device receives the third information, the access network device may send a signaling to the terminal, where the signaling may be used to inform the terminal to release the context of the first session, and the information carries indication information for indicating the new allowed network slice identifier.

It can be seen that, in the embodiment of the present application, the access network device sends signaling to the AMF network element to notify that the network slice does not support the session identifier established on the network slice; secondly, the AMF network element receives signaling from the access network equipment to acquire that the network slice does not support the session identification established on the network slice; then, the SMF network element receives the indication information from the AMF network element to know that the network slice does not support the session identification established on the network slice; finally, the SMF network element performs releasing the session and notifies the AMF network element. Through the signaling interaction between the access network and the core network element, the method is beneficial to realizing the rapid release of the session established on the network slice which is not supported by the access network equipment, reduces the signaling interaction in the session release process and saves the signaling overhead. In addition, the control plane resource or the context of the session is released in time, so that the waste of network resources is reduced.

The scheme of the embodiment of the application is mainly introduced from the aspect of interaction among the network elements in the method side. It will be appreciated that the terminal, the access network device and the core network element comprise corresponding hardware structures and/or software modules for performing the respective functions in order to achieve the above-mentioned functions. Those of skill in the art will readily appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as hardware or combinations of hardware and computer software. Whether a function is implemented as hardware or computer software driven hardware depends upon the particular application and design constraints imposed on the solution. Those skilled in the art may implement the described functionality using different approaches for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

The embodiment of the application can divide the functional units of the terminal, the access network equipment and the core network element according to the method example, for example, each functional unit can be divided corresponding to each function, and two or more functions can be integrated in one processing unit. The integrated units described above may be implemented either in hardware or in software program modules. It should be noted that, in the embodiment of the present application, the division of the units is schematic, but only one logic function is divided, and another division manner may be adopted in actual implementation.

In case of using integrated units, fig. 9 illustrates a functional unit composition block diagram of a session release device. The session release apparatus 900 is applied to a terminal, and specifically includes: a processing unit 902 and a communication unit 903. The processing unit 902 is configured to control and manage actions of the terminal, for example, the processing unit 902 is configured to support the terminal to perform the steps in fig. 4 and other processes for the techniques described herein. The communication unit 903 is used to support communication between the terminal device and other devices. The terminal may further comprise a storage unit 901 for storing program code and data of the terminal.

The processing unit 902 may be a processor or controller, such as a central processing unit (central processing unit, CPU), a general purpose processor, a digital signal processor (DIGITAL SIGNAL processor, DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (field programmable GATE ARRAY, FPGA), or other programmable logic device, transistor logic device, hardware component, or any combination thereof. Which may implement or perform the various exemplary logical blocks, modules, and circuits described in connection with the present disclosure. The processor 902 may also be a combination that performs computing functions, e.g., including one or more microprocessor combinations, a combination of a DSP and a microprocessor, and the like. The communication unit 903 may be a communication interface, a transceiver circuit, or the like, and the storage unit 901 may be a memory. When the processing unit 902 is a processor, the communication unit 903 is a communication interface, and the storage unit 901 is a memory, the session release device 900 according to the embodiment of the present application may be a terminal shown in fig. 13.

In particular implementation, the processing unit 902 is configured to perform any step performed by the terminal in the above method embodiment, and when performing data transmission such as sending, the communication unit 903 is optionally invoked to complete a corresponding operation. The following is a detailed description.

The processing unit 902 is configured to: receiving, by the communication unit 903, first information from the access network device; determining that the access network equipment does not support the first network slice according to the first information; the first session established on the first network slice is released.

It can be seen that, in the embodiment of the present application, by receiving the information from the access network device to determine the network slice that is not supported by the access network device, the session established on the network slice is advantageously released quickly, signaling interaction in the session release process is reduced, and signaling overhead is saved.

In one possible example, the first information includes first indication information for indicating network slices supported by the access network device; the processing unit 902 is configured to determine, according to the first information, that the access network device does not support the first network slice: determining that the access network equipment does not support the first network slice according to the first indication information and the first allowed network slice identifier; or determining that the access network equipment does not support the first network slice according to the first indication information and the network slice identification of the currently established protocol data unit session.

In one possible example, the first indication information is carried in the system information.

In one possible example, the processing unit 902 is further configured to: and when the first session is established on the first network slice, switching from the current idle state to the connected state through a registration flow or a service request flow to release the first session.

In one possible example, the first information includes second indication information for indicating that the access network device does not support the first network slice and/or third indication information for indicating that the protocol data unit session identification of the first session is released.

In one possible example, the second indication information and/or the third indication information is carried in a radio resource control message.

In one possible example, the first session established on the first network slice is released, and the processing unit 902 is configured to: the first session is released according to the radio resource control message.

In the case of an integrated unit, fig. 10 illustrates a functional unit composition block diagram of a fork-type conversation release. The session release apparatus 1000 is applied to an access network device, and specifically includes: a processing unit 1002, and a communication unit 1003. The processing unit 1002 is configured to control and manage actions of the access network device, e.g., the processing unit 1002 is configured to support the access network device to perform the steps of fig. 4 or 8 and/or other processes for the techniques described herein. The communication unit 1003 is configured to support communication of the access network device with other devices. The access network device may further comprise a storage unit 1001 for storing program code and data of the access network device.

The processing unit 1002 may be a processor or controller, such as a CPU, general-purpose processor, DSP, ASIC, FPGA, or other programmable logic device, transistor logic device, hardware components, or any combination thereof. Which may implement or perform the various exemplary logical blocks, modules, and circuits described in connection with the present disclosure. The processor 1002 may also be a combination of computing functions, e.g., including one or more microprocessor combinations, a combination of a DSP and a microprocessor, etc. The communication unit 1003 may be a communication interface, a transceiver circuit, or the like, and the storage unit 1001 may be a memory. When the processing unit 1002 is a processor, the communication unit 1003 is a communication interface, and the storage unit 1001 is a memory, the session release apparatus 1000 according to the embodiment of the present application may be an access network device shown in fig. 14.

In particular implementation, the processing unit 1002 is configured to perform any step performed by the access network device in the above method embodiment, and when performing data transmission such as sending, the communication unit 1003 is optionally invoked to complete a corresponding operation. The following is a detailed description.

The processing unit 1002 is configured to: the second information is sent to the access and mobility management function AMF network element by the communication unit 1003, where the second information includes fourth indication information and fifth indication information, where the fourth indication information is used to indicate that the access network device does not support the first network slice, and the fifth indication information is used to indicate that a protocol data unit session identifier of the first session established on the first network slice is released.

It can be seen that in the embodiment of the present application, signaling is sent to the AMF network element to notify that the network slice does not support the session identifier established on the network slice, so that the session established on the network slice that is not supported by the access network device is released quickly, signaling interaction in the session release process is reduced, and signaling overhead is saved.

In one possible example, the processing unit 1002 is further to: the first information is transmitted to the terminal through the communication unit 1003, and is used for the terminal to perform the following operations: determining, according to the first information, that the access network device does not support the first network slice; the first session established on the first network slice is released.

In one possible example, the first information includes first indication information for indicating network slice identities supported by the access network device.

In one possible example, the first indication information is carried in a system message.

In one possible example, the processing unit 1002 is further to: the third information from the AMF network element is received by the communication unit 1003, the third information comprising tenth indication information for instructing the access network device to release the first session and eleventh indication information for instructing the second allowed network slice identity.

In case of using integrated units, fig. 11 illustrates a functional unit composition block diagram of a fork-type session release device. The session release apparatus 1100 is applied to an access and mobility management function AMF network element, and specifically includes: a processing unit 1102 and a communication unit 1103. The processing unit 1102 is configured to control and manage actions of the AMF network element, e.g., the processing unit 1102 is configured to support the AMF network element to perform the steps in fig. 8 and/or other processes for the techniques described herein. The communication unit 1103 is configured to support communication between the AMF network element and other devices. The AMF network element may further comprise a storage unit 1101 for storing program code and data of the AMF network element.

The processing unit 1102 may be a processor or controller, such as a CPU, general-purpose processor, DSP, ASIC, FPGA, or other programmable logic device, transistor logic device, hardware components, or any combination thereof. Which may implement or perform the various exemplary logical blocks, modules, and circuits described in connection with the present disclosure. The processor 1102 may also be a combination of computing functions, e.g., including one or more microprocessor combinations, a combination of a DSP and a microprocessor, etc. The communication unit 1103 may be a communication interface, a transceiver circuit, or the like, and the storage unit 1101 may be a memory. When the processing unit 1102 is a processor, the communication unit 1103 is a communication interface, and the storage unit 1101 is a memory, the session release apparatus 1100 according to the embodiment of the present application may be an AMF network element shown in fig. 15.

In particular, the processing unit 1102 is configured to perform any step performed by the AMF network element in the above-described method embodiment, and optionally invoke the communication unit 1103 to perform a corresponding operation when performing data transmission such as sending. The following is a detailed description.

The processing unit 1102 is configured to: the second information from the access network device is received by the communication unit 1103, where the second information includes fourth indication information and fifth indication information, the fourth indication information is used to indicate that the access network device does not support the first network slice, and the fifth indication information is used to indicate that the protocol data unit session identifier of the first session established on the first network slice is released.

It can be seen that in the embodiment of the present application, by receiving the signaling from the access network device, the session identifier that is not supported by the network slice and is established on the network slice is known, which is favorable for implementing quick release of the session that is established on the network slice that is not supported by the access network device, reducing signaling interaction in the session release process, and saving signaling overhead.

In one possible example, the processing unit 1102 is further configured to: the sixth indication information and the seventh indication information are sent to the session management function SMF network element by the communication unit 1103, where the sixth indication information is used to indicate that the access network device does not support the first network slice, and the seventh indication information is used to indicate that the protocol data unit session identifier of the first session is released.

In one possible example, the processing unit 1102 is further configured to: the communication unit 1103 receives eighth indication information from the SMF network element, where the eighth indication information is used to instruct the AMF network element to release the first session.

In one possible example, the processing unit 1102 is further configured to: a ninth indication information from the SMF network element is received by the communication unit 1103, where the ninth indication information is used to indicate that the access network device does not support the first network slice.

In one possible example, the processing unit 1102 is further configured to: and sending, by the communication unit 1103, third information to the access terminal device, where the third information includes tenth indication information and eleventh indication information, where the tenth indication information is used to instruct the access network device to release the first session, and the eleventh indication information is used to instruct the second allowed network slice identifier.

In case of using integrated units, fig. 12 illustrates a functional unit composition block diagram of still another session releasing means. The session release apparatus 1200 is applied to a session management function SMF network element, and specifically includes: a processing unit 1202 and a communication unit 1203. The processing unit 1202 is configured to control and manage actions of the SMF network element, e.g., the processing unit 1202 is configured to support the SMF network element to perform the steps in fig. 8 and/or other processes for the techniques described herein. The communication unit 1203 is configured to support communication between the SMF network element and other devices. The SMF network element may further comprise a storage unit 1201 for storing program codes and data of the SMF network element.

The processing unit 1202 may be a processor or controller, such as a CPU, general-purpose processor, DSP, ASIC, FPGA, or other programmable logic device, transistor logic device, hardware component, or any combination thereof. Which may implement or perform the various exemplary logical blocks, modules, and circuits described in connection with the present disclosure. The processor 1202 may also be a combination that performs computing functions, such as including one or more microprocessor combinations, a combination of a DSP and a microprocessor, and the like. The communication unit 1203 may be a communication interface, a transceiver, a transceiving circuit, etc., and the storage unit 1201 may be a memory. When the processing unit 1202 is a processor, the communication unit 1203 is a communication interface, and the storage unit 1201 is a memory, the session release apparatus 1200 according to the embodiment of the present application may be an AMF network element shown in fig. 15.

In particular implementation, the processing unit 1202 is configured to perform any step performed by the SMF network element in the above method embodiment, and when performing data transmission such as sending, the communication unit 1203 is optionally invoked to complete a corresponding operation. The following is a detailed description.

The processing unit 1202 is configured to: the communication unit 1203 receives, from the AMF network element, sixth indication information and seventh indication information, where the sixth indication information is used to indicate that the access network device does not support the first network slice, and the seventh indication information is used to indicate that the protocol data unit session identifier of the first session established on the first network slice is released.

It can be seen that in the embodiment of the present application, by receiving the indication information from the AMF network element, the session identifier that is not supported by the network slice and is established on the network slice is known, which is favorable for implementing quick release of the session that is established on the network slice that is not supported by the access network device, reducing signaling interaction in the session release process, and saving signaling overhead.

In one possible example, the processing unit 1202 is further configured to: the eighth indication information is sent to the AMF network element by the communication unit 1203, where the eighth indication information is used to instruct the AMF network element to release the first session.

In one possible example, the processing unit 1202 is further configured to: and sending, by the communication unit 1203, ninth indication information to the AMF network element, where the ninth indication information is used to indicate that the access network device does not support the first network slice.

Referring to fig. 13, fig. 13 is a schematic structural diagram of a terminal 1300 according to an embodiment of the present application. Wherein terminal 1300 includes a processor 1310, a memory 1320, a communication interface 1330, and at least one communication bus for connecting processor 1310, memory 1320, communication interface 1330.

Memory 1320 includes, but is not limited to, random access memory (random Access Memory, RAM), read-only memory (ROM), erasable programmable read-only memory (erasable programmable read only memory, EPROM), or portable read-only memory (compact disc read-only memory, CD-ROM), memory 1320 for associated instructions and data.

The communication interface 1330 is used to receive and transmit data.

The processor 1310 may be one or more CPUs, and in the case where the processor 1310 is one CPU, the CPU may be a single-core CPU or a multi-core CPU.

It should be noted that the processor 1310 in the terminal 1300 is configured to read one or more program codes 1321 stored in the memory 1320, perform the method in the method embodiment shown in fig. 4, and the method on the terminal side of the foregoing method embodiment of the present application may also be used by the terminal 1300, which is not described herein.

Referring to fig. 14, fig. 14 is a schematic structural diagram of an access network device 1400 according to an embodiment of the present application. The access network device 1400 comprises a processor 1410, a memory 1420, a communication interface 1430 and at least one communication bus for connecting the processor 1410, the memory 1420, the communication interface 1430.

Memory 1420 includes, but is not limited to, random access memory, read only memory, erasable programmable read only memory, or portable read only memory, with memory 620 for associated instructions and data.

Communication interface 1430 is used to receive and transmit data.

The processor 1410 may be one or more CPUs, and in the case where the processor 1410 is one CPU, the CPU may be a single core CPU or a multi-core CPU.

It should be noted that the processor 1410 in the access network device 1400 is configured to read one or more program codes 1421 stored in the memory 1420, perform the method in the method embodiment shown in fig. 4 or fig. 8, and the access network device 1400 may also be configured to perform the method on the access network device side in the foregoing method embodiment of the present application, which is not described herein again.

Referring to fig. 15, fig. 15 is a schematic structural diagram of an access and mobility management function network element 1500 according to an embodiment of the present application. The access and mobility management function network element 1500 comprises a processor 1510, a memory 1520, a communication interface 1530 and at least one communication bus for connecting the processor 1510, the memory 1520, the communication interface 1530.

Memory 1520 includes, but is not limited to, random access memory, read only memory, erasable programmable read only memory, or portable read only memory, with memory 1520 for associated instructions and data.

The communication interface 1530 is for receiving and transmitting data.

The processor 1510 may be one or more CPUs, and in the case where the processor 1510 is one CPU, the CPU may be a single-core CPU or a multi-core CPU.

It should be noted that the processor 1510 in the access and mobility management function network element 1500 is configured to read one or more program codes 1521 stored in the memory 1520, perform the method in the method embodiment shown in fig. 4 or fig. 8, and the access and mobility management function network element 1500 may also be used to perform the method on the AMF network element side in the foregoing method embodiment of the present application, which is not described herein again.

Referring to fig. 16, fig. 16 is a schematic structural diagram of a session management function network element 1600 according to an embodiment of the present application. The session management function network element 1600 includes a processor 1610, a memory 1620, a communication interface 1630, and at least one communication bus for connecting the processor 1610, the memory 1620, and the communication interface 1630.

The memory 1620 includes, but is not limited to, a random access memory, a read only memory, an erasable programmable read only memory, or a portable read only memory, with the memory 1620 configured for associated instructions and data.

Communication interface 1630 is used for receiving and transmitting data.

Processor 1610 may be one or more CPUs, which may be a single core CPU or a multi-core CPU in the case where processor 1610 is a single CPU.

It should be noted that the processor 1610 in the session management function network element 1600 is configured to read one or more program codes 1621 stored in the memory 1620, perform the method in the method embodiment shown in fig. 4 or fig. 8, and the session management function network element 1600 may also be configured to perform the method on the SMF network element side in the foregoing method embodiment of the present application, which is not described herein.

The embodiment of the application also provides a chip, wherein the chip comprises a processor, and the processor is used for calling and running a computer program from a memory, so that a device provided with the chip executes part or all of the steps described by the terminal, the access network device, the access and mobility management function network element or the session management function network element in the embodiment of the method.

The embodiments of the present application also provide a computer readable storage medium storing a computer program for electronic data exchange, and the computer program is operable to cause a computer to perform part or all of the steps described in the terminal, access network device, access and mobility management function network element or session management function network element in the method embodiments described above.

The embodiments of the present application also provide a computer program product, wherein the computer program product comprises a computer program and the computer program is operable to cause a computer to perform some or all of the steps described in the terminal, the access network device, the access and mobility management function network element or the session management function network element in the embodiments of the method described above. The computer program product may be a software installation package.

The steps of a method or algorithm described in connection with the embodiments disclosed herein may be embodied in hardware, or may be embodied in software instructions executed by a processor. The software instructions may be comprised of corresponding software modules that may be stored in random access memory RAM, flash memory, ROM, EPROM, electrically Erasable Programmable ROM (EEPROM), registers, hard disk, a removable disk, a compact disk read-only memory (CD-ROM), or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor such the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium may be integral to the processor. The processor and the storage medium may reside in an Application Specific Integrated Circuit (ASIC). In addition, the ASIC may reside in an access network device, a network device, or a core network gateway. The processor and the storage medium may reside as discrete components in an access network device, or core network gateway.

Those skilled in the art will appreciate that in one or more of the examples described above, the functions described in the embodiments of the present application may be implemented, in whole or in part, in 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. When loaded and executed on a computer, produces a flow or function in accordance with embodiments of the present application, in whole or in part. The computer may be a general purpose computer, a special purpose computer, a computer network, or other programmable apparatus. 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 by a wired (e.g., coaxial cable, fiber optic, digital subscriber line), or wireless (e.g., infrared, wireless, microwave, etc.). Computer readable storage media can be any available media that can be accessed by a computer or data storage devices, such as servers, data centers, etc., that contain an integration of one or more available media. The usable medium may be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., digital video disk), or a semiconductor medium (e.g., solid state disk), etc.

The foregoing detailed description of the embodiments of the present application further illustrates the purposes, technical solutions and advantageous effects of the embodiments of the present application, and it should be understood that the foregoing is merely a specific implementation of the embodiments of the present application, and is not intended to limit the scope of the embodiments of the present application, and any modifications, equivalent substitutions, improvements, etc. made on the basis of the technical solutions of the embodiments of the present application should be included in the scope of the embodiments of the present application.

Claims

1. A session release method, comprising:

The method comprises the steps that a terminal receives first information from access network equipment, wherein the first information is determined through the current connection management state of the terminal, and the connection management comprises the steps of establishing and releasing signaling connection of an N1 interface between the terminal and a mobility management function (AMF) network element;

The terminal determines that the access network equipment does not support a first network slice according to the first information;

the terminal releases a first session established on the first network slice.

2. The method of claim 1, wherein the first information comprises first indication information, the first indication information being used to indicate network slice identifiers supported by the access network device;

the terminal determines that the access network device does not support a first network slice according to the first information, including:

The terminal determines that the access network equipment does not support the first network slice according to the first indication information and a first allowed network slice identifier; or alternatively

And the terminal determines that the access network equipment does not support the first network slice according to the first indication information and the network slice identifier of the currently established protocol data unit session.

3. The method of claim 2, wherein the first indication information is carried in system information.

4. A method according to claim 2 or 3, further comprising:

And the terminal changes from the current idle state to the connected state through a registration flow or a service request flow under the condition that the first session is established on the first network slice so as to release the first session.

5. The method according to claim 1, wherein the first information comprises second indication information for indicating that the access network device does not support the first network slice and/or third indication information for indicating that a protocol data unit session identity of the first session is released.

6. The method according to claim 5, wherein the second indication information and/or the third indication information is carried in a radio resource control message.

7. The method of claim 6, wherein the terminal releases the first session established on the first network slice, comprising:

and the terminal releases the first session according to the radio resource control message.

8. A session release method, comprising:

The access network equipment sends second information to an access and mobility management function (AMF) network element, wherein the second information comprises fourth indication information and fifth indication information, the fourth indication information is used for indicating that the access network equipment does not support a first network slice, and the fifth indication information is used for indicating to release a Protocol Data Unit (PDU) session identifier of a first session established on the first network slice;

Further comprises:

The access network device sends first information to a terminal, the first information is determined according to the current connection management state of the terminal, the connection management comprises the steps of establishing and releasing the signaling connection of an N1 interface between the terminal and the AMF network element, and the first information is used for the terminal to execute the following operations: determining, according to the first information, that the access network device does not support the first network slice; releasing the first session established on the first network slice.

9. The method of claim 8, wherein the first information comprises first indication information, the first indication information being used to indicate network slice identities supported by the access network device.

10. The method of claim 9, wherein the first indication information is carried in system information.

11. The method according to claim 8, wherein the first information comprises second indication information for indicating that the access network device does not support the first network slice and/or third indication information for indicating that a protocol data unit session identity of the first session is released.

12. The method according to claim 11, wherein the second indication information and/or the third indication information is carried in a radio resource control message.

13. The method as recited in claim 8, further comprising:

And receiving third information from the AMF network element, wherein the third information comprises tenth indication information and eleventh indication information, the tenth indication information is used for indicating the access network equipment to release the first session, and the eleventh indication information is used for indicating a second allowed network slice identifier.

14. A session release method, comprising:

An access and mobility management function (AMF) network element receives second information from access network equipment, wherein the second information comprises fourth indication information and fifth indication information, the fourth indication information is used for indicating that the access network equipment does not support a first network slice, and the fifth indication information is used for indicating that a protocol data unit session identifier of a first session established on the first network slice is released;

The AMF network element sends sixth indication information and seventh indication information to a session management function SMF network element, wherein the sixth indication information is used for indicating that the access network equipment does not support the first network slice, and the seventh indication information is used for indicating that a protocol data unit session identifier of the first session is released;

the AMF network element receives ninth indication information from the SMF network element, wherein the ninth indication information is used for indicating that the access network equipment does not support the first network slice; the ninth indication information is sent by the SMF network element to the AMF network element in response to the pre-configuration not being present at network deployment or requiring updating of the pre-configuration, the pre-configuration being used to ensure that the AMF network element knows that the access network device does not support the first network slice.

15. The method as recited in claim 14, further comprising:

The AMF network element receives eighth indication information from the SMF network element, wherein the eighth indication information is used for indicating the AMF network element to release the first session.

16. The method according to claim 14 or 15, further comprising:

the AMF network element sends third information to the access network equipment, wherein the third information comprises tenth indication information and eleventh indication information, the tenth indication information is used for indicating the access network equipment to release the first session, and the eleventh indication information is used for indicating a second allowed network slice identifier.

17. A session release method, comprising:

The method comprises the steps that a Session Management Function (SMF) network element receives sixth indication information and seventh indication information from an access and mobility management function (AMF) network element, wherein the sixth indication information is used for indicating that access network equipment does not support a first network slice, and the seventh indication information is used for indicating to release a Protocol Data Unit (PDU) session identifier of a first session established on the first network slice; the sixth indication information and the seventh indication information are sent after the AMF network element receives second information from an access network device, the second information includes fourth indication information and fifth indication information, the fourth indication information is used for indicating that the access network device does not support a first network slice, and the fifth indication information is used for indicating to release a protocol data unit session identifier of a first session established on the first network slice;

The SMF network element sends ninth indication information to the AMF network element in response to the pre-configuration being not available or the pre-configuration needing to be updated in network deployment, where the ninth indication information is used to indicate that the access network device does not support the first network slice, and the pre-configuration is used to ensure that the AMF network element knows that the access network device does not support the first network slice.

18. The method as recited in claim 17, further comprising:

and the SMF network element sends eighth indication information to the AMF network element, wherein the eighth indication information is used for indicating the AMF network element to release the first session.

19. A session release device, characterized in that it is applied to a terminal, said device comprising a processing unit and a communication unit; the processing unit is used for:

receiving, by the communication unit, first information from an access network device, where the first information is determined by a current connection management state of the terminal, where the connection management includes establishing and releasing a signaling connection of an N1 interface between the terminal and a mobility management function AMF network element;

determining that the access network equipment does not support a first network slice according to the first information;

Releasing the first session established on the first network slice.

20. The apparatus of claim 19, wherein the first information is first indication information, the first indication information being used to indicate network slice identifiers supported by the access network device;

The processing unit is configured to determine, according to the first information, that the access network device does not support a first network slice, where:

determining that the access network equipment does not support the first network slice according to the first indication information and a first allowed network slice identifier; or alternatively

And determining that the access network equipment does not support the first network slice according to the first indication information and the network slice identifier of the currently established protocol data unit session.

21. The apparatus of claim 20, wherein the first indication information is carried in system information.

22. The apparatus of claim 20 or 21, wherein the processing unit is further configured to:

and when the first session is established on the first network slice, switching from the current idle state to the connected state through a registration flow or a service request flow so as to release the first session.

23. The apparatus according to claim 19, wherein the first information comprises second indication information for indicating that the access network device does not support the first network slice and/or third indication information for indicating that a protocol data unit session identity of the first session is released.

24. The apparatus according to claim 23, wherein the second indication information and/or the third indication information is carried in a radio resource control message.

25. The apparatus of claim 24, wherein the releasing the first session established on the first network slice, the processing unit is configured to:

and releasing the first session according to the radio resource control message.

26. A session release device, characterized in that it is applied to an access network apparatus, said device comprising a processing unit and a communication unit; the processing unit is used for:

Sending second information to an access and mobility management function (AMF) network element through the communication unit, wherein the second information comprises fourth indication information and fifth indication information, the fourth indication information is used for indicating that the access network equipment does not support a first network slice, and the fifth indication information is used for indicating that a Protocol Data Unit (PDU) session identifier of a first session established on the first network slice is released;

the processing unit is further configured to:

Transmitting, by the communication unit, first information to a terminal, where the first information is determined by a current connection management state of the terminal, where the connection management includes establishing and releasing a signaling connection of an N1 interface between the terminal and the AMF network element, and the first information is used by the terminal to perform the following operations: determining, according to the first information, that the access network device does not support the first network slice; releasing the first session established on the first network slice.

27. The apparatus of claim 26, wherein the first information comprises first indication information, the first indication information being used to indicate network slice identities supported by the access network device.

28. The apparatus of claim 27, wherein the first indication information is carried in system information.

29. The apparatus according to claim 26, wherein the first information comprises second indication information for indicating that the access network device does not support the first network slice and/or third indication information for indicating that a protocol data unit session identity of the first session is released.

30. The apparatus according to claim 29, wherein the second indication information and/or the third indication information is carried in a radio resource control message.

31. The apparatus of claim 26, wherein the processing unit is further configured to:

And receiving third information from the AMF network element through the communication unit, wherein the third information comprises tenth indication information and eleventh indication information, the tenth indication information is used for indicating the access network equipment to release the first session, and the eleventh indication information is used for indicating a second allowed network slice identifier.

32. A session release device, characterized in that it is applied to an access and mobility management function AMF network element, said device comprising a processing unit and a communication unit; the processing unit is used for:

Receiving, by the communication unit, second information from an access network device, where the second information includes fourth indication information and fifth indication information, where the fourth indication information is used to indicate that the access network device does not support a first network slice, and the fifth indication information is used to indicate a protocol data unit session identifier that releases a first session established on the first network slice;

the processing unit is further configured to:

Transmitting sixth indication information and seventh indication information to a Session Management Function (SMF) network element through the communication unit, wherein the sixth indication information is used for indicating that the access network equipment does not support the first network slice, and the seventh indication information is used for indicating that a Protocol Data Unit (PDU) session identifier of the first session is released;

the processing unit is further configured to:

Receiving, by the communication unit, ninth indication information from the SMF network element, where the ninth indication information is used to indicate that the access network device does not support the first network slice; the ninth indication information is sent by the SMF network element to the AMF network element in response to the pre-configuration not being present at network deployment or requiring updating of the pre-configuration, the pre-configuration being used to ensure that the AMF network element knows that the access network device does not support the first network slice.

33. The apparatus of claim 32, wherein the processing unit is further configured to:

And receiving eighth indication information from the SMF network element through the communication unit, wherein the eighth indication information is used for indicating the AMF network element to release the first session.

34. The apparatus of claim 32 or 33, wherein the processing unit is further configured to:

And sending third information to the access network equipment through the communication unit, wherein the third information comprises tenth indication information and eleventh indication information, the tenth indication information is used for indicating the access network equipment to release the first session, and the eleventh indication information is used for indicating a second allowed network slice identifier.

35. A session release device, characterized in that it is applied to a session management function SMF network element, said device comprising a processing unit and a communication unit; the processing unit is used for:

Receiving, by the communication unit, sixth indication information and seventh indication information from an AMF network element, where the sixth indication information is used to indicate that an access network device does not support a first network slice, and the seventh indication information is used to indicate to release a protocol data unit session identifier of a first session established on the first network slice; the sixth indication information and the seventh indication information are sent after the AMF network element receives second information from an access network device, the second information includes fourth indication information and fifth indication information, the fourth indication information is used for indicating that the access network device does not support a first network slice, and the fifth indication information is used for indicating to release a protocol data unit session identifier of a first session established on the first network slice;

the processing unit is further configured to:

and in response to the pre-configuration being not performed or the pre-configuration needing to be updated during network deployment, sending ninth indication information to the AMF network element through the communication unit, wherein the ninth indication information is used for indicating that the access network equipment does not support the first network slice, and the pre-configuration is used for ensuring that the AMF network element knows that the access network equipment does not support the first network slice.

36. The apparatus of claim 35, wherein the processing unit is further configured to:

and sending eighth indication information to the AMF network element through the communication unit, wherein the eighth indication information is used for indicating the AMF network element to release the first session.

37. A terminal comprising a processor, a memory, a communication interface, and one or more programs stored in the memory and configured to be executed by the processor, the programs comprising instructions for performing the steps in the method of any of claims 1-7.

38. An access network device comprising a processor, a memory, a communication interface, and one or more programs stored in the memory and configured to be executed by the processor, the programs comprising instructions for performing the steps in the method of any of claims 8-13.

39. An access and mobility management function, AMF, network element comprising a processor, a memory, a communication interface, and one or more programs stored in the memory and configured to be executed by the processor, the programs comprising instructions for performing the steps in the method of any of claims 14-16.

40. A session management function, SMF, network element, comprising a processor, a memory, a communication interface, and one or more programs stored in the memory and configured to be executed by the processor, the programs comprising instructions for performing the steps in the method of claim 17 or 18.

41. A chip, comprising: a processor for calling and running a computer program from a memory, causing a device on which the chip is mounted to perform the method of any of claims 1-7, 8-13, 14-16 or 17-18.

42. A computer-readable storage medium, characterized in that it stores a computer program for electronic data exchange, wherein the computer program causes a computer to perform the method according to any one of claims 1-7, 8-13, 14-16 or 17-18.